CODES

ADOPTS WITH AMENDMENTS:

International Energy Conservation Code 2012 (IECC 2012)

Copyright

Preface

Chapter 1 Administration

Chapter 2 [Ce] Definitions

Chapter 3 [Ce] General Requirements

Chapter 4 [Ce] Commercial Energy Efficiency

Chapter 5 [Ce] Referenced Standards

Chapter 1 Administration

Chapter 2 [Re] Definitions

Chapter 3 [Re] General Requirements

Chapter 4 [Re] Residential Energy Efficiency

Chapter 5 [Re] Referenced Standards

The requirements contained in this chapter are applicable to commercial buildings, or portions of commercial buildings.

Commercial buildings shall comply with one of the following:

  1. The requirements of ANSI/ASHRAE/IESNA 90.1.
  2. The requirements of Sections C402, C403, C404 and C405. In addition, commercial buildings shall comply with either Section C406.2, C406.3 or C406.4.
  3. The requirements of Section C407, C402.4, C403.2, C404, C405.2, C405.3, C405.4, C405.6 and C405.7. The building energy cost shall be equal to or less than 85 percent of the standard reference design building.

Additions, alterations and repairs to existing buildings shall comply with one of the following:

  1. Sections C402, C403, C404 and C405; or
  2. ANSI/ASHRAE/IESNA 90.1.
The building thermal envelope shall comply with Section C402.1.1. Section C402.1.2 shall be permitted as an alternative to the R-values specified in Section C402.1.1.
The building thermal envelope shall meet the requirements of Tables C402.2 and C402.3 based on the climate zone specified in Chapter 3. Commercial buildings or portions of commercial buildings enclosing Group R occupancies shall use the R-values from the “Group R” column of Table C402.2. Commercial buildings or portions of commercial buildings enclosing occupancies other than Group R shall use the R-values from the “All other” column of Table C402.2. Buildings with a vertical fenestration area or skylight area that exceeds that allowed in Table C402.3 shall comply with the building envelope provisions of ANSI/ASHRAE/IESNA 90.1.

An assembly with a U-factor, C-factor, or F-factor equal or less than that specified in Table C402.1.2 shall be permitted as an alternative to the R-value in Table C402.2. Commercial buildings or portions of commercial buildings enclosing Group R occupancies shall use the U-factor, C-factor, or F-factor from the “Group R” column of Table C402.1.2. Commercial buildings or portions of commercial buildings enclosing occupancies other than Group R shall use the U-factor, C-factor or Ffactor from the “All other” column of Table C402.1.2.

TABLE C402.1.2

OPAQUE THERMAL ENVELOPE ASSEMBLY REQUIREMENTSa

CLIMATE ZONE1234 EXCEPT MARINE5 AND MARINE 4678
All otherGroup RAll otherGroup RAll otherGroup RAll otherGroup RAll otherGroup RAll otherGroup RAll otherGroup RAll otherGroup R
Roofs
Insulation entirely above deckU-0.048U-0.048U-0.048U-0.048U-0.048U-0.048U-0.039U-0.039U-0.039U-0.039U-0.032U-0.032U-0.028U-0.028U-0.028U-0.028
Metal buildingsU-0.044U-0.035U-0.035U-0.035U-0.035U-0.035U-0.035U-0.035U-0.035U-0.035U-0.031U-0.031U-0.029U-0.029U-0.029U-0.029
Attic and otherU-0.027U-0.027U-0.027U-0.027U-0.027U-0.027U-0.027U-0.027U-0.027U-0.021U-0.021U-0.021U-0.021U-0.021U-0.021U-0.021
Walls, Above Grade
MassU-0.142U-0.142U-0.142U-0.123U-0.110U-0.104U-0.104U-0.090U-0.078U-0.078U-0.078U-0.071U-0.061U-0.061U-0.061U-0.061
Metal buildingU-0.079U-0.079U-0.079U-0.079U-0.079U-0.052U-0.052U-0.052U-0.052U-0.052U-0.052U-0.052U-0.052U-0.039U-0.052U-0.039
Metal framedU-0.077U-0.077U-0.077U-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.057U-0.064U-0.052U-0.045U-0.045
Wood framed and otherU-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.064U-0.051U-0.051U-0.051U-0.051U-0.036U-0.036
Walls, Below Grade
Below-grade wallbC-1.140C-1.140C-1.140C-1.140C-1.140C-1.140C-0.119C-0.119C-0.119C-0.119C-0.119C-0.119C-0.092C-0.092C-0.092C-0.092
Floors
MassU-0.322U-0.322U-0.107U-0.087U-0.076U-0.076U-0.076U-0.074U-0.074U-0.064U-0.064U-0.057U-0.055U-0.051U-0.055U-0.051
Joist/framingU-0.066U-0.066U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033U-0.033
Slab-on-Grade Floors
Unheated slabsF-0.73F-0.73F-0.73F-0.73F-0.73F-0.73F-0.54F-0.54F-0.54F-0.54F-0.54F-0.52F-0.40F-0.40F-0.40F-0.40
Heated slabsF-0.70F-0.70F-0.70F-0.70F-0.70F-0.70F-0.65F-0.65F-0.58F-0.58F-0.58F-0.58F-0.55F-0.55F-0.55F-0.55
  1. Use of opaque assembly U-factors, C-factors, and F-factors from ANSI/ASHRAE/IESNA 90.1 Appendix A shall be permitted, provided the construction complies with the applicable construction details from ANSI/ASHRAE/IESNA 90.1 Appendix A.
  2. Where heated slabs are below grade, below-grade walls shall comply with the F-factor requirements for heated slabs.

Opaque assemblies shall comply with Table C402.2. Where two or more layers of continuous insulation board are used in a construction assembly, the continuous insulation boards shall be installed in accordance with Section C303.2. If the continuous insulation board manufacturer’s installation instructions do not address installation of two or more layers, the edge joints between each layer of continuous insulation boards shall be staggered.

TABLE C402.2

OPAQUE THERMAL ENVELOPE REQUIREMENTSa

CLIMATE ZONE1234 EXCEPT MARINE5 AND MARINE 4678
All OtherGroup RAll OtherGroup RAll OtherGroup RAll OtherGroup RAll OtherGroup RAll OtherGroup RAll OtherGroup RAll OtherGroup R
Roofs
Insulation entirely above deckR-20ciR-20ciR-20ciR-20ciR-20ciR-20ciR-25ciR-25ciR-25ciR-25ciR-30ciR-30ciR-35ciR-35ciR-35ciR-35ci
Metal buildings (with R-5 thermal blocks)a, bR-19 +
R-11 LS
R-19 +
R-11 LS
R-19 + R11 LSR-19 +
R-11 LS
R-19 +
R-11 LS
R-19 +
R-11 LS
R-19 +
R-11 LS
R-19 +
R-11 LS
R-19 +
R-11 LS
R-19 +
R-11 LS
R-25 +
R-11 LS
R-25 +
R-11 LS
R-30 +
R-11 LS
R-30 +
R-11 LS
R-30 +
R-11 LS
R-30 +
R-11 LS
Attic and otherR-38R-38R-38R-38R-38R-38R-38R-38R-38R-49R-49R-49R-49R-49R-49R-49
Walls, Above Grade
MasscR-5.7cicR-5.7cicR-5.7cicR-7.6ciR-7.6ciR-9.5ciR-9.5ciR-11.4ciR-11.4ciR-13.3ciR-13.3ciR-15.2ciR-15.2ciR-15.2ciR-25ciR-25ci
Metal buildingR-13+
R-6.5ci
R-13 +
R-6.5ci
R13 +
R-6.5ci
R-13 +
R-13ci
R-13 +
R-6.5ci
R-13 +
R-13ci
R-13 +
R-13ci
R-13 +
R-13ci
R-13 +
R-13ci
R-13 +
R-13ci
R-13 +
R-13ci
R-13 +
R-13ci
R-13 +
R-13ci
R-13+
R-19.5ci
R-13 +
R-13ci
R-13+
R-19.5ci
Metal framedR-13 +
R-5ci
R-13 +
R-5ci
R-13 +
R-5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-7.5ci
R-13 +
R-15.6ci
R-13 +
R-7.5ci
R-13+ R17.5ci
Wood framed and otherR-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-3.8ci or R-20
R-13 +
R-7.5ci or R-20 +
R-3.8ci
R-13 +
R-7.5ci or R-20 +
R-3.8ci
R-13 +
R-7.5ci or R-20 +
R-3.8ci
R-13 +
R-7.5ci or R-20 +
R-3.8ci
R-13 +
R-7.5ci or R-20 +
R-3.8ci
R-13 +
R-15.6ci or R-20 + R-10ci
R-13 +
R-15.6ci or R-20 + R-10ci
Walls, Below Grade
Below-grade walldNRNRNRNRNRNRR-7.5ciR-7.5ciR-7.5ciR-7.5ciR-7.5ciR-7.5ciR-10ciR-10ciR-10ciR-12.5ci
Floors
MassNRNRR-6.3ciR-8.3ciR-10ciR-10ciR-10ciR-10.4ciR-10ciR-12.5ciR-12.5ciR-12.5ciR-15ciR-16.7ciR-15ciR-16.7ci
Joist/framingNRNRR-30R-30R-30R-30R-30R-30R-30R-30R-30R-30eR-30eR-30eR-30eR-30e
Slab-on-Grade Floors
Unheated slabsNRNRNRNRNRNRR-10 for 24″ belowR-10 for 24″ belowR-10 for 24″ belowR-10 for 24″ belowR-10 for 24″ belowR-15 for 24″ belowR-15 for 24″ belowR-15 for 24″ belowR-15 for 24″ belowR-20 for 24″ below
Heated slabsdR-7.5 for 12″ belowR-7.5 for 12″ belowR-7.5 for 12″ belowR-7.5 for 12″ belowR-10 for 24″ belowR-10 for 24″ belowR-15 for 24″ belowR-15 for 24″ belowR-15 for 36″ belowR-15 for 36″ belowR-15 for 36″ belowR-20 for 48″ belowR-20 for 24″ belowR-20 for 48″ belowR-20 for 48″ belowR-20 for 48″ below
Opaque Doors
SwingingU-0.61U-0.61U-0.61U-0.61U-0.61U-0.61U-0.61U-0.61U-0.37U-0.37U-0.37U-0.37U-0.37U-0.37U-0.37U-0.37
Roll-up or slidingR-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75R-4.75

For SI: 1 inch = 25.4 mm. ci = Continuous insulation. NR = No requirement.

LS = Liner System—A continuous membrane installed below the purlins and uninterrupted by framing members. Uncompressed, unfaced insulation rests on top of the membrane between the purlins.

  1. Assembly descriptions can be found in ANSI/ASHRAE/IESNA Appendix A.
  2. Where using R-value compliance method, a thermal spacer block shall be provided, otherwise use the U-factor compliance method in Table C402.1.2.
  3. R-5.7ci is allowed to be substituted with concrete block walls complying with ASTM C 90, ungrouted or partially grouted at 32 inches or less on center vertically and 48 inches or less on center horizontally, with ungrouted cores filled with materials having a maximum thermal conductivity of 0.44 Btu-in/h-f2 °F.
  4. Where heated slabs are below grade, below-grade walls shall comply with the exterior insulation requirements for heated slabs.
  5. Steel floor joist systems shall be insulated to R-38.

The minimum thermal resistance (R-value) of the insulating material installed either between the roof framing or continuously on the roof assembly shall be as specified in Table C402.2, based on construction materials used in the roof assembly. Skylight curbs shall be insulated to the level of roofs with insulation entirely above deck or R-5, whichever is less.

Exceptions:

  1. Continuously insulated roof assemblies where the thickness of insulation varies 1 inch (25 mm) or less and where the area-weighted U-factor is equivalent to the same assembly with the R-value specified in Table C402.2.
  2. Unit skylight curbs included as a component of an NFRC 100 rated assembly shall not be required to be insulated.

Insulation installed on a suspended ceiling with removable ceiling tiles shall not be considered part of the minimum thermal resistance of the roof insulation.

Low-sloped roofs, with a slope less than 2 units vertical in 12 horizontal, directly above cooled conditioned spaces in Climate Zones 1, 2, and 3 shall comply with one or more of the options in Table C402.2.1.1.

Exceptions: The following roofs and portions of roofs are exempt from the requirements in Table C402.2.1.1:

  1. Portions of roofs that include or are covered by:

    1. 1.1. Photovoltaic systems or components.
    2. 1.2. Solar air or water heating systems or components.
    3. 1.3. Roof gardens or landscaped roofs.
    4. 1.4. Above-roof decks or walkways.
    5. 1.5. Skylights.
    6. 1.6. HVAC systems, components, and other opaque objects mounted above the roof.
  2. Portions of roofs shaded during the peak sun angle on the summer solstice by permanent features of the building, or by permanent features of adjacent buildings.
  3. Portions of roofs that are ballasted with a minimum stone ballast of 17 pounds per square foot (psf) (74 kg/m2) or 23 psf (117 kg/m2) pavers.
  4. Roofs where a minimum of 75 percent of the roof area meets a minimum of one of the exceptions above.

TABLE C402.2.1.1

MINIMUM ROOF REFLECTANCE AND EMITTANCE OPTIONSa

Three-year aged solar reflectanceb of 0.55 and three-year aged thermal
emittancec of 0.75
Initial solar reflectanceb of 0.70 and initial thermal emittancec of
0.75
Three-year-aged solar reflectance indexd of 64
Initial solar reflectance indexd of 82
  1. The use of area-weighted averages to meet these requirements shall be permitted. Materials lacking initial tested values for either solar reflectance or thermal emittance, shall be assigned both an initial solar reflectance of 0.10 and an initial thermal emittance of 0.90. Materials lacking three-year aged tested values for either solar reflectance or thermal emittance shall be assigned both a three-year aged solar reflectance of 0.10 and a three-year aged thermal emittance of 0.90.
  2. Solar reflectance tested in accordance with ASTM C 1549, ASTM E 903 or ASTM E 1918.
  3. Thermal emittance tested in accordance with ASTM C 1371 or ASTM E 408.
  4. Solar reflectance index (SRI) shall be determined in accordance with ASTM E 1980 using a convection coefficient of 2.1 Btu/h × ft2 ×°F (12W/ m2 × K). Calculation of aged SRI shall be based on aged tested values of solar reflectance and thermal emittance. Calculation of initial SRI shall be based on initial tested values of solar reflectance and thermal emittance.
Walls associated with the building envelope shall be classified in accordance with Section C402.2.2.1 or C402.2.2.2.
Above-grade walls are those walls covered by Section C402.2.3 on the exterior of the building and completely above grade or walls that are more than 15 percent above grade.
Below-grade walls covered by Section C402.2.4 are basement or first-story walls associated with the exterior of the building that are at least 85 percent below grade.

The minimum thermal resistance (R-value) of the insulating materials installed in the wall cavity between the framing members and continuously on the walls shall be as specified in Table C402.2, based on framing type and construction materials used in the wall assembly. The R-value of integral insulation installed in concrete masonry units (CMU) shall not be used in determining compliance with Table C402.2.

“Mass walls” shall include walls weighing not less than:

  1. 35 psf (170 kg/m2) of wall surface area; or
  2. 25 psf (120 kg/m2) of wall surface area if the material weight is not more than 120 pounds per cubic foot (pcf) (1900 kg/m3).
The minimum thermal resistance (R-value) of the insulating material installed in, or continuously on, the below-grade walls shall be as specified in Table C402.2, and shall extend to a depth of 10 feet (3048 mm) below the outside finished ground level, or to the level of the floor, whichever is less.

The minimum thermal resistance (R-value) of the insulating material installed either between the floor framing or continuously on the floor assembly shall be as specified in Table C402.2, based on construction materials used in the floor assembly.

“Mass floors” shall include floors weighing not less than:

  1. 35 psf (170 kg/m2) of floor surface area; or
  2. 25 psf (120 kg/m2) of floor surface area if the material weight is not more than 120 pcf (1,900 kg/m3).

Where the slab on grade is in contact with the ground, the minimum thermal resistance (R-value) of the insulation around the perimeter of unheated or heated slab-on-grade floors shall be as specified in Table C402.2. The insulation shall be placed on the outside of the foundation or on the inside of the foundation wall. The insulation shall extend downward from the top of the slab for a minimum distance as shown in the table or to the top of the footing, whichever is less, or downward to at least the bottom of the slab and then horizontally to the interior or exterior for the total distance shown in the table. Insulation extending away from the building shall be protected by pavement or by a minimum of 10 inches (254 mm) of soil.

Exception: Where the slab-on-grade floor is greater than 24 inches (61 mm) below the finished exterior grade, perimeter insulation is not required.

Opaque doors (doors having less than 50 percent glass area) shall meet the applicable requirements for doors as specified in Table C402.2 and be considered as part of the gross area of above-grade walls that are part of the building envelope.
Radiant panels, and associated U-bends and headers, designed for sensible heating of an indoor space through heat transfer from the thermally effective panel surfaces to the occupants or indoor space by thermal radiation and natural convection and the bottom surfaces of floor structures incorporating radiant heating shall be insulated with a minimum of R-3.5 (0.62 m2/K × W).

Fenestration shall comply with Table C402.3. Automatic daylighting controls specified by this section shall comply with Section C405.2.2.3.2.

TABLE C402.3

BUILDING ENVELOPE REQUIREMENTS: FENESTRATION

CLIMATE ZONE1234 EXCEPT MARINE5 AND MARINE 4678
Vertical fenestration
U-factor
Fixed fenestration0.500.500.460.380.380.360.290.29
Operable fenestration0.650.650.600.450.450.430.370.37
Entrance doors1.100.830.770.770.770.770.770.77
SHGC
SHGC0.250.250.250.400.400.400.450.45
Skylights
U-factor0.750.650.550.500.500.500.500.50
SHGC0.350.350.350.400.400.40NRNR

NR = No requirement.

The vertical fenestration area (not including opaque doors and opaque spandrel panels) shall not exceed 30 percent of the gross above-grade wall area. The skylight area shall not exceed 3 percent of the gross roof area.

In Climate Zones 1 through 6, a maximum of 40 percent of the gross above-grade wall area shall be permitted to be vertical fenestration, provided:

  1. No less than 50 percent of the conditioned floor area is within a daylight zone;
  2. Automatic daylighting controls are installed in daylight zones; and
  3. Visible transmittance (VT) of vertical fenestration is greater than or equal to 1.1 times solar heat gain coefficient (SHGC).

Exception: Fenestration that is outside the scope of NFRC 200 is not required to comply with Item 3.

The skylight area shall be permitted to be a maximum of 5 percent of the roof area provided automatic daylighting controls are installed in daylight zones under skylights.

In an enclosed space greater than 10,000 square feet (929 m2), directly under a roof with ceiling heights greater than 15 feet (4572 mm), and used as an office, lobby, atrium, concourse, corridor, storage, gymnasium/exercise center, convention center, automotive service, manufacturing, nonrefrigerated warehouse, retail store, distribution/sorting area, transportation, or workshop, the total daylight zone under skylights shall be not less than half the floor area and shall provide a minimum skylight area to daylight zone under skylights of either:

  1. Not less than 3 percent with a skylight VT of at least 0.40; or
  2. Provide a minimum skylight effective aperture of at least 1 percent determined in accordance with Equation C4-1.

(Equation C4-1)

where:

Skylight area=Total fenestration area of skylights.
Skylight VT=Area weighted average visible transmittance of skylights.
WF=Area weighted average well factor, where well factor is 0.9 if light well depth is less than 2 feet (610 mm), or 0.7 if light well depth is 2 feet (610 mm) or greater.
Light well depth=Measure vertically from the underside of the lowest point of the skylight glazing to the ceiling plane under the skylight.

Exception: Skylights above daylight zones of enclosed spaces are not required in:

  1. Buildings in climate zones 6 through 8.
  2. Spaces where the designed general lighting power densities are less than 0.5 W/ft2 (5.4 W/m2).
  3. Areas where it is documented that existing structures or natural objects block direct beam sunlight on at least half of the roof over the enclosed area for more than 1,500 daytime hours per year between 8 am and 4 pm.
  4. Spaces where the daylight zone under rooftop monitors is greater than 50 percent of the enclosed space floor area.

All lighting in the daylight zone shall be controlled by multilevel lighting controls that comply with Section C405.2.2.3.3.

Exception: Skylights above daylight zones of enclosed spaces are not required in:

  1. Buildings in Climate Zones 6 through 8.
  2. Spaces where the designed general lighting power densities are less than 0.5 W/ft2(5.4 W/m2).
  3. Areas where it is documented that existing structures or natural objects block direct beam sunlight on at least half of the roof over the enclosed area for more than 1,500 daytime hours per year between 8 am and 4 pm.
  4. Spaces where the daylight zone under rooftop monitors is greater than 50 percent of the enclosed space floor area.

Skylights in office, storage, automotive service, manufacturing, nonrefrigerated warehouse, retail store, and distribution/sorting area spaces shall have a glazing material or diffuser with a measured haze factor greater than 90 percent when tested in accordance with ASTM D 1003.

Exception: Skylights designed to exclude direct sunlight entering the occupied space by the use of fixed or automated baffles, or the geometry of skylight and light well need not comply with Section C402.3.2.2.

For vertical fenestration, the maximum U-factor and solar heat gain coefficient (SHGC) shall be as specified in Table C402.3, based on the window projection factor. For skylights, the maximum U-factor and solar heat gain coefficient (SHGC) shall be as specified in Table C402.3.

The window projection factor shall be determined in accordance with Equation C4-2.

(Equation C4-2)

where:

PF=Projection factor (decimal).
A=Distance measured horizontally from the furthest continuous extremity of any overhang, eave, or permanently attached shading device to the vertical surface of the glazing.
B=Distance measured vertically from the bottom of the glazing to the underside of the overhang, eave, or permanently attached shading device.

Where different windows or glass doors have different PF values, they shall each be evaluated separately.

Where the fenestration projection factor for a specific vertical fenestration product is greater than or equal to 0.2, the required maximum SHGC from Table C402.3 shall be adjusted by multiplying the required maximum SHGC by the multiplier specified in Table C402.3.3.1 corresponding with the orientation of the fenestration product and the projection factor.

TABLE C402.3.3.1

SHGC ADJUSTMENT MULTIPLIERS

PROJECTION
FACTOR
ORIENTED WITHIN 45
DEGREES OF TRUE NORTH
ALL OTHER
ORIENTATION
0.2 ≤ PF < 0.51.11.2
PF ≥ 0.51.21.6
In Climate Zones 1, 2 and 3, vertical fenestration entirely located not less than 6 feet (1729 mm) above the finished floor shall be permitted a maximum SHGC of 0.40.
In Climate Zones 1 through 6, skylights shall be permitted a maximum SHGC of 0.60 where located above daylight zones provided with automated daylighting controls.
Where skylights are installed above daylight zones provided with automatic daylighting controls, a maximum U-factor of 0.9 shall be permitted in Climate Zones 1 through 3; and a maximum U-factor of 0.75 shall be permitted in Climate Zones 4 through 8.
For compliance with Section C402.3.3, the SHGC for dynamic glazing shall be determined using the manufacturer’s lowest-rated SHGC, and the VT/SHGC ratio shall be determined using the maximum VT and maximum SHGC. Dynamic glazing shall be considered separately from other fenestration, and area-weighted averaging with other fenestration that is not dynamic glazing shall not be permitted.
An area-weighted average shall be permitted to satisfy the U-factor requirements for each fenestration product category listed in Table C402.3. Individual fenestration products from different fenestration product categories listed in Table C402.3 shall not be combined in calculating area-weighted average U-factor.

The thermal envelope of buildings shall comply with Sections C402.4.1 through C402.4.8.

A continuous air barrier shall be provided throughout the building thermal envelope. The air barriers shall be permitted to be located on the inside or outside of the building envelope, located within the assemblies composing the envelope, or any combination thereof. The air barrier shall comply with Sections C402.4.1.1 and C402.4.1.2.

Exception: Air barriers are not required in buildings located in Climate Zones 1, 2 and 3.

The continuous air barrier shall be constructed to comply with the following:

  1. The air barrier shall be continuous for all assemblies that are the thermal envelope of the building and across the joints and assemblies.
  2. Air barrier joints and seams shall be sealed, including sealing transitions in places and changes in materials. Air barrier penetrations shall be sealed in accordance with Section C402.4.2. The joints and seals shall be securely installed in or on the joint for its entire length so as not to dislodge, loosen or otherwise impair its ability to resist positive and negative pressure from wind, stack effect and mechanical ventilation.
  3. Recessed lighting fixtures shall comply with Section C402.4.8. Where similar objects are installed which penetrate the air barrier, provisions shall be made to maintain the integrity of the air barrier.

Exception: Buildings that comply with Section C402.4.1.2.3 are not required to comply with Items 1 and 3.

A continuous air barrier for the opaque building envelope shall comply with Section C402.4.1.2.1, C402.4.1.2.2, or C402.4.1.2.3.

Materials with an air permeability no greater than 0.004 cfm/ft2 (0.02 L/s • m2) under a pressure differential of 0.3 inches water gauge (w.g.) (75 Pa) when tested in accordance with ASTM E 2178 shall comply with this section. Materials in Items 1 through 15 shall be deemed to comply with this section provided joints are sealed and materials are installed as air barriers in accordance with the manufacturer’s instructions.

  1. Plywood with a thickness of not less than 3/8 inch (10 mm).
  2. Oriented strand board having a thickness of not less than 3/8 inch (10 mm).
  3. Extruded polystyrene insulation board having a thickness of not less than 1/2 inch (12 mm).
  4. Foil-back polyisocyanurate insulation board having a thickness of not less than 1/2 inch (12 mm).
  5. Closed cell spray foam a minimum density of 1.5 pcf (2.4 kg/m3) having a thickness of not less than 11/2 inches (36 mm).
  6. Open cell spray foam with a density between 0.4 and 1.5 pcf (0.6 and 2.4 kg/m3) and having a thickness of not less than 4.5 inches (113 mm).
  7. Exterior or interior gypsum board having a thickness of not less than 1/2 inch (12 mm).
  8. Cement board having a thickness of not less than 1/2 inch (12 mm).
  9. Built up roofing membrane.
  10. Modified bituminous roof membrane.
  11. Fully adhered single-ply roof membrane.
  12. A Portland cement/sand parge, or gypsum plaster having a thickness of not less than 5/8 inch (16 mm).
  13. Cast-in-place and precast concrete.
  14. Fully grouted concrete block masonry.
  15. Sheet steel or aluminum.

Assemblies of materials and components with an average air leakage not to exceed 0.04 cfm/ft2 (0.2 L/s • m2) under a pressure differential of 0.3 inches of water gauge (w.g.)(75 Pa) when tested in accordance with ASTM E 2357, ASTM E 1677 or ASTM E 283 shall comply with this section. Assemblies listed in Items 1 and 2 shall be deemed to comply provided joints are sealed and requirements of Section C402.4.1.1 are met.

  1. Concrete masonry walls coated with one application either of block filler and two applications of a paint or sealer coating;
  2. A Portland cement/sand parge, stucco or plaster minimum 1/ 2 inch (12 mm) in thickness.

The completed building shall be tested and the air leakage rate of the building envelope shall not exceed 0.40 cfm/ft2 at a pressure differential of 0.3 inches water gauge (2.0 L/s • m2 at 75 Pa) in accordance with ASTM E 779 or an equivalent method approved by the code official.

Penetrations of the air barrier and paths of air leakage shall be caulked, gasketed or otherwise sealed in a manner compatible with the construction materials and location. Joints and seals shall be sealed in the same manner or taped or covered with a moisture vapor-permeable wrapping material. Sealing materials shall be appropriate to the construction materials being sealed. The joints and seals shall be securely installed in or on the joint for its entire length so as not to dislodge, loosen or otherwise impair its ability to resist positive and negative pressure from wind, stack effect and mechanical ventilation.

The air leakage of fenestration assemblies shall meet the provisions of Table C402.4.3. Testing shall be in accordance with the applicable reference test standard in Table C402.4.3 by an accredited, independent testing laboratory and labeled by the manufacturer.

Exceptions:

  1. Field-fabricated fenestration assemblies that are sealed in accordance with Section C402.4.1.
  2. Fenestration in buildings that comply with Section C402.4.1.2.3 are not required to meet the air leakage requirements in Table C402.4.3.

TABLE C402.4.3

MAXIMUM AIR INFILTRATION RATE FOR FENESTRATION ASSEMBLIES

FENESTRATION
ASSEMBLY
MAXIMUM
RATE(CFM/FT2)
TEST
PROCEDURE
Windows0.20aAAMA/WDMA/CSA101/I.S.2/A440
or
NFRC 400
Sliding doors0.20a
Swinging doors0.20a
Skylights – with condensation weepage openings0.30
Skylights – all other0.20a
Curtain walls0.06NFRC 400
or
ASTM E 283 at 1.57 psf
(75 Pa)
Storefront glazing0.06
Commercial glazed
swinging entrance doors
1.00
Revolving doors1.00
Garage doors0.40ANSI/DASMA 105,
NFRC 400, or
ASTM E 283 at 1.57 psf
(75 Pa)
Rolling doors1.00

For SI: 1 cubic foot per minute = 0.47L/s, 1 square foot = 0.093 m2.

  1. The maximum rate for windows, sliding and swinging doors, and skylights is permitted to be 0.3 cfm per square foot of fenestration or door area when tested in accordance with AAMA/WDMA/CSA101/I.S.2/A440 at 6.24 psf (300 Pa).

Doors and access openings from conditioned space to shafts, chutes, stairways and elevator lobbies shall either meet the requirements of Section C402.4.3 or shall be gasketed, weatherstripped or sealed.

Exception: Door openings required to comply with Section 716 or 716.4 of the International Building Code; or doors and door openings required by the International Building Code to comply with UL 1784 shall not be required to comply with Section C402.4.4.

Stairway enclosures and elevator shaft vents and other outdoor air intakes and exhaust openings integral to the building envelope shall be provided with dampers in accordance with Sections C402.4.5.1 and C402.4.5.2.

Stairway and shaft vents shall be provided with Class I motorized dampers with a maximum leakage rate of 4 cfm/ft2 (20.3 L/s • m2) at 1.0 inch water gauge (w.g.) (249 Pa) when tested in accordance with AMCA 500D.

Stairway and shaft vent dampers shall be installed with controls so that they are capable of automatically opening upon:

  1. The activation of any fire alarm initiating device of the building’s fire alarm system; or
  2. The interruption of power to the damper.

Outdoor air supply and exhaust openings shall be provided with Class IA motorized dampers with a maximum leakage rate of 4 cfm/ft2 (20.3 L/s • m2) at 1.0 inch water gauge (w.g.) (249 Pa) when tested in accordance with AMCA 500D.

Exceptions:

  1. Gravity (nonmotorized) dampers having a maximum leakage rate of 20 cfm/ft2 (101.6 L/s • m2) at 1.0 inch water gauge (w.g.) (249 Pa) when tested in accordance with AMCA 500D are permitted to be used as follows:

    1. 1.1. In buildings for exhaust and relief dampers.
    2. 1.2. In buildings less than three stories in height above grade.
    3. 1.3. For ventilation air intakes and exhaust and relief dampers in buildings of any height located in Climate Zones 1, 2 and 3.
    4. 1.4. Where the design outdoor air intake or exhaust capacity does not exceed 300 cfm (141 L/s).

    Gravity (nonmotorized) dampers for ventilation air intakes shall be protected from direct exposure to wind.

  2. Dampers smaller than 24 inches (610 mm) in either dimension shall be permitted to have a leakage of 40 cfm/ft2 (203.2 L/s • m2) at 1.0 inch water gauge (w.g.) (249 Pa) when tested in accordance with AMCA 500D.
  3. Any grease duct serving a Type I hood installed in accordance with Section 506.3 of the International Mechanical Code shall not be required to have a motorized or gravity damper.
Cargo doors and loading dock doors shall be equipped with weatherseals to restrict infiltration when vehicles are parked in the doorway.

All building entrances shall be protected with an enclosed vestibule, with all doors opening into and out of the vestibule equipped with self-closing devices. Vestibules shall be designed so that in passing through the vestibule it is not necessary for the interior and exterior doors to open at the same time. The installation of one or more revolving doors in the building entrance shall not eliminate the requirement that a vestibule be provided on any doors adjacent to revolving doors.

Exceptions:

  1. Buildings in Climate Zones 1 and 2.
  2. Doors not intended to be used by the public, such as doors to mechanical or electrical equipment rooms, or intended solely for employee use.
  3. Doors opening directly from a sleeping unit or dwelling unit.
  4. Doors that open directly from a space less than 3,000 square feet (298 m2) in area.
  5. Revolving doors.
  6. Doors used primarily to facilitate vehicular movement or material handling and adjacent personnel doors.
Recessed luminaires installed in the building thermal envelope shall be sealed to limit air leakage between conditioned and unconditioned spaces. All recessed luminaires shall be IC-rated and labeled as having an air leakage rate or not more 2.0 cfm (0.944 L/s) when tested in accordance with ASTM E 283 at a 1.57 psf (75 Pa) pressure differential. All recessed luminaires installed in the thermal envelope shall be sealed with a gasket or caulk between the housing and interior wall or ceiling covering.

Mechanical systems and equipment serving the building heating, cooling or ventilating needs shall comply with Section C403.2 (referred to as the mandatory provisions) and either:

  1. Section C403.3 (Simple systems); or
  2. Section C403.4 (Complex systems).
Mechanical systems and equipment serving the building heating, cooling or ventilating needs shall comply with Sections C403.2.1 through C403.2.11.
Design loads shall be determined in accordance with the procedures described in ANSI/ASHRAE/ACCA Standard 183. The design loads shall account for the building envelope, lighting, ventilation and occupancy loads based on the project design. Heating and cooling loads shall be adjusted to account for load reductions that are achieved where energy recovery systems are utilized in the HVAC system in accordance with the ASHRAE HVAC Systems and Equipment Handbook. Alternatively, design loads shall be determined by an approved equivalent computation procedure, using the design parameters specified in Chapter 3.

The output capacity of heating and cooling equipment and systems shall not exceed the loads calculated in accordance with Section C403.2.1. A single piece of equipment providing both heating and cooling shall satisfy this provision for one function with the capacity for the other function as small as possible, within available equipment options.

Exceptions:

  1. Required standby equipment and systems provided with controls and devices that allow such systems or equipment to operate automatically only when the primary equipment is not operating.
  2. Multiple units of the same equipment type with combined capacities exceeding the design load and provided with controls that have the capability to sequence the operation of each unit based on load.

Equipment shall meet the minimum efficiency requirements of Tables C403.2.3(1), C403.2.3(2), C403.2.3(3), C403.2.3(4), C403.2.3(5), C403.2.3(6), C403.2.3(7) and C403.2.3(8) when tested and rated in accordance with the applicable test procedure. Plate-type liquid-to-liquid heat exchangers shall meet the minimum requirements of Table C403.2.3(9). The efficiency shall be verified through certification under an approved certification program or, if no certification program exists, the equipment efficiency ratings shall be supported by data furnished by the manufacturer. Where multiple rating conditions or performance requirements are provided, the equipment shall satisfy all stated requirements. Where components, such as indoor or outdoor coils, from different manufacturers are used, calculations and supporting data shall be furnished by the designer that demonstrates that the combined efficiency of the specified components meets the requirements herein.

TABLE C403.2.3(1)

MINIMUM EFFICIENCY REQUIREMENTS: ELECTRICALLY OPERATED UNITARY AIR CONDITIONERS AND CONDENSING UNITS

EQUIPMENT TYPESIZE CATEGORYHEATING
SECTION TYPE
SUBCATEGORY OR
RATING CONDITION
MINIMUM EFFICIENCYTEST
PROCEDUREa
Before 6/1/2011As of 6/1/2011
Air conditioners,
air cooled
< 65,000 Btu/hbAllSplit System13.0 SEER13.0 SEERAHRI 210/240
Single Package13.0 SEER13.0 SEER
Through-the-wall
(air cooled)
≤ 30,000 Btu/hbAllSplit system12.0 SEER12.0 SEER
Single Package12.0 SEER12.0 SEER
Small-duct high-velocity
(air cooled)
< 65,000 Btu/hbAllSplit System10.0 SEER10.0 SEER
Air conditioners,
air cooled
≥ 65,000 Btu/h
and
< 135,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.2 EER
11.4 IEER
11.2 EER
11.4 IEER
AHRI 340/360
All otherSplit System and
Single Package
11.0 EER
11.2 IEER
11.0 EER
11.2 IEER
≥ 135,000 Btu/h
and
< 240,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.2 IEER
11.0 EER
11.2 IEER
All otherSplit System and
Single Package
10.8 EER
11.0 IEER
10.8 EER
11.0 IEER
≥ 240,000 Btu/h
and
< 760,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
10.0 EER
10.1 IEER
10.0 EER
10.1 IEER
All otherSplit System and
Single Package
9.8 EER
9.9 IEER
9.8 EER
9.9 IEER
≥ 760,000 Btu/hElectric Resistance
(or None)
Split System and
Single Package
9.7 EER
9.8 IEER
9.7 EER
9.8 IEER
All otherSplit System and
Single Package
9.5 EER
9.6 IEER
9.5 EER
9.6 IEER
Air conditioners,
water cooled
< 65,000 Btu/hbAllSplit System and
Single Package
12.1 EER
12.3 IEER
12.1 EER
12.3 IEER
AHRI 210/240
≥ 65,000 Btu/h
and
< 135,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.5 EER
11.7 IEER
12.1 EER
12.3 IEER
AHRI 340/360
All otherSplit System and
Single Package
11.3 EER
11.5 IEER
11.9 EER
12.1 IEER
≥ 135,000 Btu/h
and
< 240,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.2 IEER
12.5 EER
12.7 IEER
All otherSplit System and
Single Package
10.8 EER
11.0 IEER
12.3 EER
12.5 IEER
≥ 240,000 Btu/h
and
< 760,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.1 EER
12.4 EER
12.6 EER
All otherSplit System and
Single Package
10.8 EER
10.9 EER
12.2 EER
12.4 EER
≥ 760,000 Btu/hElectric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.1 EER
12.0 EER
12.4 EER
All otherSplit System and
Single Package
10.8 EER
10.9 EER
12.0 EER
12.2 EER
Air conditioners,
evaporatively cooled
< 65,000 Btu/hbAllSplit System and
Single Package
12.1 EER
12.3 IEER
12.1 EER
12.3 IEER
AHRI 210/240
≥ 65,000 Btu/h
and
< 135,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.5 EER
11.7 IEER
12.1 EER
12.3 IEER
AHRI 340/360
All otherSplit System and
Single Package
11.3 EER
11.5 IEER
11.9 EER
12.1 IEER
≥ 135,000 Btu/h
and
< 240,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.2 IEER
12.0 EER
12.2 IEER
All otherSplit System and
Single Package
10.8 EER
11.0 IEER
11.8 EER
12.0 IEER
≥ 240,000 Btu/h
and
< 760,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.1 EER
11.9 EER
12.1 EER
All otherSplit System and
Single Package
10.8 EER
10.9 EER
12.2 EER
11.9 EER
≥ 760,000 Btu/hElectric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.1 EER
11.7 EER
11.9 EER
All otherSplit System and
Single Package
10.8 EER
10.9 EER
11.5 EER
11.7 EER
Condensing units,
air cooled
≥ 135,000 Btu/h10.1 EER
11.4 IEER
10.5 EER
14.0 IEER
AHRI 365
Condensing units,
water cooled
≥ 135,000 Btu/h13.1 EER
13.6 IEER
13.5 EER
14.0 IEER
Condensing units,
evaporatively cooled
≥ 135,000 Btu/h13.1 EER
13.6 IEER
13.5 EER
14.0 IEER

For SI:1 British thermal unit per hour = 0.2931 W.

  1. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the reference year version of the test procedure.
  2. Single-phase, air-cooled air conditioners less than 65,000 Btu/h are regulated by NAECA. SEER values are those set by NAECA.

TABLE C403.2.3(2)

MINIMUM EFFICIENCY REQUIREMENTS: ELECTRICALLY OPERATED UNITARY AND APPLIED HEAT PUMPS

EQUIPMENT TYPESIZE CATEGORYHEATING SECTION TYPESUBCATEGORY OR
RATING CONDITION
MINIMUM EFFICIENCYTEST
PROCEDUREa
Air cooled
(cooling mode)
< 65,000 Btu/hbAllSplit System13.0 SEERAHRI 210/240
Single Packaged13.0 SEER
Through-the-wall,
air cooled
≤ 30,000 Btu/hbAllSplit System13.0 SEER
Single Packaged13.0 SEER
Single-duct high-velocity
air cooled
< 65,000 Btu/hbAllSplit System10.0 SEER
Air cooled
(cooling mode)
≥ 65,000 Btu/h
and
< 135,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
11.0 EER
11.2 IEER
AHRI 340/360
All otherSplit System and
Single Package
10.8 EER
11.0 IEER
≥ 135,000 Btu/h
and
< 240,000 Btu/h
Electric Resistance
(or None)
Split System and
Single Package
10.6 EER
10.7 IEER
All otherSplit System and
Single Package
10.4 EER
10.5 IEER
≥ 240,000 Btu/hElectric Resistance
(or None)
Split System and
Single Package
9.5 EER
9.6 IEER
All otherSplit System and
Single Package
9.3 EER
9.4 IEER
Water source
(cooling mode)
< 17,000 Btu/hAll86°F entering water11.2 EERISO 13256-1
≥ 17,000 Btu/h and
< 65,000 Btu/h
All86°F entering water12.0 EER
≥ 65,000 Btu/h and
< 135,000 Btu/h
All86°F entering water12.0 EER
Ground water source
(cooling mode)
< 135,000 Btu/hAll59°F entering water16.2 EER
All77°F entering water13.4 EER
Water-source water to water (cooling mode)< 135,000 Btu/hAll86°F entering water10.6 EERISO 13256-2
59°F entering water16.3 EER
Ground water source
Brine to water
(cooling mode)
< 135,000 Btu/hAll77°F entering fluid12.1 EER
Air cooled
(heating mode)
< 65,000 Btu/hbSplit System7.7 HSPFAHRI 210/240
Single Package7.7 HSPF
Through-the-wall,
(air cooled, heating mode)
≤ 30,000 Btu/hb
(cooling capacity)
Split System7.4 HSPF
Single Package7.4 HSPF
Small-duct high velocity
(air cooled, heating mode)
< 65,000 Btu/hbSplit System6.8 HSPF
Air cooled
(heating mode)
≥ 65,000 Btu/h and
< 135,000 Btu/h
(cooling capacity)
47°F db/43°F wb
Outdoor Air
3.3 COPAHRI 340/360
17°F db/15°F wb
Outdoor Air
2.25 COP
≥ 135,000 Btu/h
(cooling capacity)
47°F db/43°F wb
Outdoor Air
3.2 COP
17°F db/15°F wb
Outdoor Air
2.05 COP
Water source
(heating mode)
< 135,000 Btu/h
(cooling capacity)
68°F entering water4.2 COPISO 13256-1
Ground water source
(heating mode)
< 135,000 Btu/h
(cooling capacity)
50°F entering water3.6 COP
Ground source
(heating mode)
< 135,000 Btu/h
(cooling capacity)
32°F entering fluid3.1 COP
Water-source
water to water
(heating mode)
< 135,000 Btu/h
(cooling capacity)
68°F entering water3.7 COPISO 13256-2
50°F entering water3.1 COP
Ground source
brine to water
(heating mode)
< 135,000 Btu/h
(cooling capacity)
32°F entering fluid2.5 COP

For SI:1 British thermal unit per hour = 0.2931 W, °C = [(°F) - 32]/1.8.

  1. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the reference year version of the test procedure.
  2. Single-phase, air-cooled air conditioners less than 65,000 Btu/h are regulated by NAECA. SEER values are those set by NAECA.

TABLE C403.2.3(3)

MINIMUM EFFICIENCY REQUIREMENTS: ELECTRICALLY OPERATED PACKAGED TERMINAL AIR CONDITIONERS, PACKAGED TERMINAL HEAT PUMPS, SINGLE-PACKAGE VERTICAL AIR CONDITIONERS, SINGLE VERTICAL HEAT PUMPS, ROOM AIR CONDITIONERS AND ROOM AIR-CONDITIONER HEAT PUMPS

EQUIPMENT TYPESIZE CATEGORY
(INPUT)
SUBCATEGORY OR
RATING CONDITION
MINIMUM EFFICIENCYTEST
PROCEDUREa
Before 10/08/2012As of 10/08/2012
PTAC (cooling mode)
new construction
All Capacities95°F db outdoor air12.5 - (0.213 × Cap/1000) EER13.8 - (0.300 × Cap/1000) EERAHRI 310/380
PTAC (cooling mode)
replacementsb
All Capacities95°F db outdoor air10.9 - (0.213 × Cap/1000) EER10.9 - (0.213 × Cap/1000) EER
PTHP (cooling mode)
new construction
All Capacities95°F db outdoor air12.3 - (0.213 × Cap/1000) EER14.0 - (0.300 × Cap/1000) EER
PTHP (cooling mode)
replacementsb
All Capacities95°F db outdoor air10.8 - (0.213 × Cap/1000) EER10.8 - (0.213 × Cap/1000) EER
PTHP (heating mode)
new construction
All Capacities3.2 - (0.026 × Cap/1000) COP3.2 - (0.026 × Cap/1000) COP
PTHP (heating mode)
replacementsb
All Capacities2.9 - (0.026 × Cap/1000) COP2.9 - (0.026 × Cap/1000) COP
SPVAC
(cooling mode)
< 65,000 Btu/h95°F db/ 75°F wb
outdoor air
9.0 EER9.0 EERAHRI 390
≥ 65,000 Btu/h and
< 135,000 Btu/h
95°F db/ 75°F wb
outdoor air
8.9 EER8.9 EER
≥ 135,000 Btu/h and
< 240,000 Btu/h
95°F db/ 75°F wb
outdoor air
8.6 EER8.6 EER
SPVHP
(cooling mode)
< 65,000 Btu/h95°F db/ 75°F wb
outdoor air
9.0 EER9.0 EER
≥ 65,000 Btu/h and
< 135,000 Btu/h
95°F db/ 75°F wb
outdoor air
8.9 EER8.9 EER
≥ 135,000 Btu/h and
< 240,000 Btu/h
95°F db/ 75°F wb
outdoor air
8.6 EER8.6 EER
SPVHP
(heating mode)
<65,000 Btu/h47°F db/ 43°F wb
outdoor air
3.0 COP3.0 COPAHRI 390
≥ 65,000 Btu/h and
< 135,000 Btu/h
47°F db/ 43°F wb
outdoor air
3.0 COP3.0 COP
≥ 135,000 Btu/h and
< 240,000 Btu/h
47°F db/ 75°F wb
outdoor air
2.9 COP2.9 COP
Room air conditioners,
with louvered slides
< 6,000 Btu/h9.7 SEER9.7 SEERANSI/AHAMRAC-1
≥ 6,000 Btu/h and
< 8,000 Btu/h
9.7 EER9.7 EER
≥ 8,000 Btu/h and
< 14,000 Btu/h
9.8 EER9.8 EER
≥ 14,000 Btu/h and
< 20,000 Btu/h
9.7 SEER9.7 SEER
≥ 20,000 Btu/h8.5 EER8.5 EER
Room air conditioners,
without louvered slides
< 8,000 Btu/h9.0 EER9.0 EER
≥ 8,000 Btu/h and
< 20,000 Btu/h
8.5 EER8.5 EER
≥ 20,000 Btu/h8.5 EER8.5 EER
Room air-conditioner
heat pumps with
louvered sides
< 20,000 Btu/h9.0 EER9.0 EER
≥ 20,000 Btu/h8.5 EER8.5 EER
Room air-conditioner
heat pumps without
louvered sides
< 14,000 Btu/h8.5 EER8.5 EER
≥ 14,000 Btu/h8.0 EER8.0 EER
Room air conditioner
casement only
All capacities8.7 EER8.7 EER
Room air conditioner
casement-slider
All capacities9.5 EER9.5 EER

For SI: 1 British thermal unit per hour = 0.2931 W, °C = [(°F) - 32]/1.8.

“Cap” = The rated cooling capacity of the project in Btu/h. If the unit’s capacity is less than 7000 Btu/h, use 7000 Btu/h in the calculation. If the unit’s capacity is greater than 15,000 Btu/h, use 15,000 Btu/h in the calculations.

  1. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
  2. Replacement unit shall be factory labeled as follows: “MANUFACTURED FOR REPLACEMENT APPLICATIONS ONLY: NOT TO BE INSTALLED IN NEW CONSTRUCTION PROJECTS.” Replacement efficiencies apply only to units with existing sleeves less than 16 inches (406 mm) in height and less than 42 inches (1067 mm) in width.

TABLE 403.2.3(4)

WARM AIR FURNACES AND COMBINATION WARM AIR FURNACES/AIR-CONDITIONING UNITS, WARM AIR DUCT FURNACES AND UNIT HEATERS, MINIMUM EFFICIENCY REQUIREMENTS

EQUIPMENT TYPESIZE CATEGORY
(INPUT)
SUBCATEGORY OR
RATING CONDITION
MINIMUM
EFFICIENCYd, e
TEST PROCEDUREa
Warm air furnaces,
gas fired
< 225,000 Btu/h78% AFUE or
80%Etc
DOE 10 CFR Part 430
or ANSI Z21.47
≥ 225,000 Btu/hMaximum capacityc80%EtfANSI Z21.47
Warm air furnaces,
oil fired
< 225,000 Btu/h78% AFUE or
80%Etc
DOE 10 CFR Part 430
or UL 727
≥ 225,000 Btu/hMaximum capacityb81%EtgUL 727
Warm air duct furnaces,
gas fired
All capacitiesMaximum capacityb80%EcANSI Z83.8
Warm air unit heaters,
gas fired
All capacitiesMaximum capacityb80%EcANSI Z83.8
Warm air unit heaters,
oil fired
All capacitiesMaximum capacityb80%EcUL 731

For SI: 1 British thermal unit per hour = 0.2931 W.

  1. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
  2. Minimum and maximum ratings as provided for and allowed by the unit’s controls.
  3. Combination units not covered by the National Appliance Energy Conservation Act of 1987 (NAECA) (3-phase power or cooling capacity greater than or equal to 65,000 Btu/h [19 kW]) shall comply with either rating.
  4. Et = Thermal efficiency. See test procedure for detailed discussion.
  5. Ec = Combustion efficiency (100% less flue losses). See test procedure for detailed discussion.
  6. Ec = Combustion efficiency. Units must also include an IID, have jackets not exceeding 0.75 percent of the input rating, and have either power venting or a flue damper. A vent damper is an acceptable alternative to a flue damper for those furnaces where combustion air is drawn from the conditioned space.
  7. Et = Thermal efficiency. Units must also include an IID, have jacket losses not exceeding 0.75 percent of the input rating, and have either power venting or a flue damper. A vent damper is an acceptable alternative to a flue damper for those furnaces where combustion air is drawn from the conditioned space.

TABLE C403.2.3(5)

MINIMUM EFFICIENCY REQUIREMENTS: GAS- AND OIL-FIRED BOILERS

EQUIPMENT TYPEaSUBCATEGORY OR
RATING CONDITION
SIZE CATEGORY (INPUT)MINIMUM EFFICIENCYTEST PROCEDURE
Boilers, hot waterGas-fired< 300,000 Btu/h80% AFUE10 CFR Part 430
≥ 300,000 Btu/h and
≤ 2,500,000 Btu/hb
80%Et10CFR Part 431
> 2,500,00 Btu/ha82%Ec
Oil-firedc< 300,000 Btu/h80% AFUE10 CFR Part 430
≥ 300,000 Btu/h and
≤ 2,500,000 Btu/hb
82%Et10 CFR Part 431
> 2,500,000 Btu/ha84% Ec
Boilers, steamGas-fired< 300,000 Btu/h75% AFUE10 CFR Part 430
Gas-fired- all, except natural draft≥ 300,000 Btu/h and
≤ 2,500,000 Btu/hb
79%Et10CFR Part 431
> 2,500,000 Btu/ha79% Et
Gas-fired-natural draft≥ 300,000 Btu/h and
≤ 2,500,000 Btu/hb
77% Et
> 2,500,000 Btu/ha77% Et
Oil-firedc< 300,000 Btu/h80% AFUE10 CFR Part 430
≥ 300,000 Btu/h and
≤ 2,500,000 Btu/hb
81% Et10CFR Part 431
> 2,500,000 Btu/ha81%Et

For SI: 1 British thermal unit per hour = 0.2931 W.

Ec = Combustion efficiency (100 percent less flue losses). Et = Thermal efficiency. See referenced standard document for detailed information.

  1. These requirements apply to boilers with rated input of 8,000,000 Btu/h or less that are not packaged boilers and to all packaged boilers. Minimum efficiency requirements for boilers cover all capacities of packaged boilers.
  2. Maximum capacity – minimum and maximum ratings as provided for and allowed by the unit’s controls.
  3. Includes oil-fired (residual).

TABLE C403.2.3(6)

MINIMUM EFFICIENCY REQUIREMENTS: CONDENSING UNITS, ELECTRICALLY OPERATED

EQUIPMENT TYPESIZE CATEGORYMINIMUM EFFICIENCYbTEST PROCEDUREa
Condensing units, air cooled≥ 135,000 Btu/h10.1 EER
11.2 IPLV
AHRI 365
Condensing units, water or evaporatively cooled≥ 135,000 Btu/h13.1 EER
13.1 IPLV

For SI: 1 British thermal unit per hour = 0.2931 W.

  1. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
  2. IPLVs are only applicable to equipment with capacity modulation.

TABLE C403.2.3(7)

MINIMUM EFFICIENCY REQUIREMENTS: WATER CHILLING PACKAGESa

EQUIPMENT TYPESIZE
CATEGORY
UNITSBEFORE 1/1/2010AS OF 1/1/2010bTEST
PROCEDUREc
PATH APATH B
FULL
LOAD
IPLVFULL
LOAD
IPLVFULL
LOAD
IPLV
Air-cooled chillers< 150 tonsEER≥ 9.562≥ 10.4
16
≥ 9.562≥ 12.500NANAAHRI 550/590
≥ 150 tonsEER≥ 9.562≥ 12.750NANA
Air cooled without condenser, electrical
operated
All
capacities
EER≥ 10.586≥ 11.782Air-cooled chillers without condensers
shall be rated with matching condensers
and comply with the air-cooled
chiller efficiency requirements
Water cooled, electrically operated,
reciprocating
All
capacities
kW/ton≤ 0.837≤ 0.696Reciprocating units shall comply with
water cooled positive displacement
efficiency requirements
Water cooled, electrically operated, positive displacement< 75 tonskW/ton≤ 0.790≤ 0.676≤ 0.780≤ 0.630≤ 0.800≤ 0.600
≥ 75 tons
and
< 150 tons
kW/ton≤ 0.775≤ 0.615≤ 0.790≤ 0.586
≥ 150 tons
and
< 300 tons
kW/ton≤ 0.717≤ 0.627≤ 0.680≤ 0.580≤ 0.718≤ 0.540
≥ 300 tonskW/ton≤ 0.639≤ 0.571≤ 0.620≤ 0.540≤ 0.639≤ 0.490
Water cooled, electrically operated,
centrifugal
< 150 tonskW/ton≤ 0.703≤ 0.669≤ 0.634≤ 0.596≤ 0.639≤ 0.450
≥ 150 tons
and
< 300 tons
kW/ton≤ 0.634≤ 0.596
≥ 300 tons
and
< 600 tons
kW/ton≤ 0.576≤ 0.549≤ 0.576≤ 0.549≤ 0.600≤ 0.400
≥ 600 tonskW/ton≤ 0.576≤ 0.549≤ 0.570≤ 0.539≤ 0.590≤ 0.400
Air cooled, absorption single effectAll
capacities
COP≥ 0.600NR≥ 0.600NRNANAAHRI 560
Water cooled, absorption single effectAll
capacities
COP≥ 0.700NR≥ 0.700NRNANA
Absorption double effect, indirect firedAll
capacities
COP≥ 1.000≥ 1.050≥ 1.000≥ 1.050NANA
Absorption double effect, direct firedAll
capacities
COP≥ 1.000≥ 1.000≥ 1.000≥ 1.000NANA

For SI:1 ton = 3517 W, 1 British thermal unit per hour = 0.2931 W, °C = [(°F) - 32]/1.8.

NA = Not applicable, not to be used for compliance; NR = No requirement.

  1. The centrifugal chiller equipment requirements, after adjustment in accordance with Section C403.2.3.1 or Section C403.2.3.2, do not apply to chillers used in low-temperature applications where the design leaving fluid temperature is less than 36°F. The requirements do not apply to positive displacement chillers with leaving fluid temperatures less than or equal to 32°F. The requirements do not apply to absorption chillers with design leaving fluid temperatures less than 40°F.
  2. Compliance with this standard can be obtained by meeting the minimum requirements of Path A or B. However, both the full load and IPLV shall be met to fulfill the requirements of Path A or B.
  3. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.

TABLE C403.2.3(8)

MINIMUM EFFICIENCY REQUIREMENTS: HEAT REJECTION EQUIPMENT

EQUIPMENT TYPEaTOTAL SYSTEM HEAT REJECTION CAPACITY AT RATED CONDITIONSSUBCATEGORY OR RATING CONDITIONPERFORMANCE REQUIREDb, c, dTEST PROCEDUREe, f
Propeller or axial fan open circuit cooling towersAll95°F Entering Water
85°F Leaving Water
75°F Entering wb
≥ 38.2 gpm/hpCTI ATC-105 and CTI STD-201
Centrifugal fan open circuit cooling towersAll95°F Entering Water
85°F Leaving Water
75°F Entering wb
≥ 20.0 gpm/hpCTI ATC-105 and CTI STD-201
Propeller or axial fan closed circuit cooling towersAll102°F Entering Water
90°F Leaving Water
75°F Entering wb
≥ 14.0 gpm/hpCTI ATC-105S and CTI STD-201
Centrifugal closed circuit cooling towersAll102°F Entering Water
90°F Leaving Water
75°F Entering wb
≥ 7.0 gpm/hpCTI ATC-105S and CTI STD-201
Air-cooled condensersAll125°F Condensing Temperature
R-22 Test Fluid
190°F Entering Gas Temperature
15°F Subcooling
95°F Entering db
≥ 176,000 Btu/h•hpARI 460

For SI: °C = [(°F)-32]/1.8, L/s • kW = (gpm/hp)/(11.83), COP = (Btu/h • hp)/(2550.7).

db = dry bulb temperature, °F, wb = wet bulb temperature, °F.

  1. The efficiencies and test procedures for both open and closed circuit cooling towers are not applicable to hybrid cooling towers that contain a combination of wet and dry heat exchange sections.
  2. For purposes of this table, open circuit cooling tower performance is defined as the water flow rating of the tower at the thermal rating condition listed in Table 403.2.3(8) divided by the fan nameplate rated motor power.
  3. For purposes of this table, closed circuit cooling tower performance is defined as the water flow rating of the tower at the thermal rating condition listed in Table 403.2.3(8) divided by the sum of the fan nameplate rated motor power and the spray pump nameplate rated motor power.
  4. For purposes of this table, air-cooled condenser performance is defined as the heat rejected from the refrigerant divided by the fan nameplate rated motor power.
  5. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
  6. If a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, then the product shall be listed in the certification program, or, if a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, but the product is not listed in the existing certification program, the ratings shall be verified by an independent laboratory test report.

TABLE C403.2.3(9)

HEAT TRANSFER EQUIPMENT

EQUIPMENT TYPESUBCATEGORYMINIMUM EFFICIENCYTEST PROCEDUREa
Liquid-to-liquid heat exchangersPlate typeNRAHRI 400

NR = No Requirement

  1. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.

Equipment not designed for operation at AHRI Standard 550/590 test conditions of 44°F (7°C) leaving chilled-water temperature and 85°F (29°C) entering condenser water temperature with 3 gpm/ton (0.054 I/s • kW) condenser water flow shall have maximum full-load kW/ ton and NPLV ratings adjusted using Equations C4-3 and C4-4.

(Equation C4-3)

(Equation C4-4)

where:

Kadj=A × B
A=0.0000015318 × (LIFT)4 – 0.000202076 × (LIFT)3 + 0.0101800 × (LIFT)2 – 0.264958 × LIFT + 3.930196
B=0.0027 × L vg Evap (°C) + 0.982
LIFT=L vgCondL vg Evap
L vgCond=Full-load condenser leaving water temperature (°C)
L vgEvap=Full-load leaving evaporator temperature (°C)

SI units shall be used in the Kadj equation.

The adjusted full-load and NPLV values shall only be applicable for centrifugal chillers meeting all of the following full-load design ranges:

  1. The leaving evaporator fluid temperature is not less than 36°F (2.2°C).
  2. The leaving condenser fluid temperature is not greater than 115°F (46.1°C).
  3. LIFT is not less than 20°F (11.1 °C) and not greater than 80°F (44.4°C).

Exception: Centrifugal chillers designed to operate outside of these ranges need not comply with this code.

Equipment with a leaving fluid temperature higher than 32°F (0°C), shall meet the requirements of Table C403.2.3(7) when tested or certified with water at standard rating conditions, in accordance with the referenced test procedure.
Each heating and cooling system shall be provided with thermostatic controls as specified in Section C403.2.4.1, C403.2.4.2, C403.2.4.3, C403.2.4.4, C403.4.1, C403.4.2, C403.4.3 or C403.4.4.

The supply of heating and cooling energy to each zone shall be controlled by individual thermostatic controls capable of responding to temperature within the zone. Where humidification or dehumidification or both is provided, at least one humidity control device shall be provided for each humidity control system.

Exception: Independent perimeter systems that are designed to offset only building envelope heat losses or gains or both serving one or more perimeter zones also served by an interior system provided:

  1. The perimeter system includes at least one thermostatic control zone for each building exposure having exterior walls facing only one orientation (within +/-45 degrees) (0.8 rad) for more than 50 contiguous feet (15 240 mm); and
  2. The perimeter system heating and cooling supply is controlled by a thermostats located within the zones served by the system.
Heat pumps having supplementary electric resistance heat shall have controls that, except during defrost, prevent supplementary heat operation where the heat pump can meet the heating load.

Where used to control both heating and cooling, zone thermostatic controls shall provide a temperature range or deadband of at least 5°F (2.8°C) within which the supply of heating and cooling energy to the zone is capable of being shut off or reduced to a minimum.

Exception: Thermostats requiring manual changeover between heating and cooling modes.

Each zone shall be provided with thermostatic setback controls that are controlled by either an automatic time clock or programmable control system.

Exceptions:

  1. Zones that will be operated continuously.
  2. Zones with a full HVAC load demand not exceeding 6,800 Btu/h (2 kW) and having a readily accessible manual shutoff switch.
Thermostatic setback controls shall have the capability to set back or temporarily operate the system to maintain zone temperatures down to 55°F (13°C) or up to 85°F (29°C).
Automatic time clock or programmable controls shall be capable of starting and stopping the system for seven different daily schedules per week and retaining their programming and time setting during a loss of power for at least 10 hours. Additionally, the controls shall have a manual override that allows temporary operation of the system for up to 2 hours; a manually operated timer capable of being adjusted to operate the system for up to 2 hours; or an occupancy sensor.
Automatic start controls shall be provided for each HVAC system. The controls shall be capable of automatically adjusting the daily start time of the HVAC system in order to bring each space to the desired occupied temperature immediately prior to scheduled occupancy.

Both outdoor air supply and exhaust ducts shall be equipped with motorized dampers that will automatically shut when the systems or spaces served are not in use.

Exceptions:

  1. Gravity dampers shall be permitted in buildings less than three stories in height.
  2. Gravity dampers shall be permitted for buildings of any height located in Climate Zones 1, 2 and 3.
  3. Gravity dampers shall be permitted for outside air intake or exhaust airflows of 300 cfm (0.14 m3/s) or less.
  4. Any grease duct serving a Type I hood installed in accordance with Section 506.3 of the International Mechanical Code shall not be required to have a motorized or gravity damper.
Snow- and icemelting systems, supplied through energy service to the building, shall include automatic controls capable of shutting off the system when the pavement temperature is above 50°F (10°C) and no precipitation is falling and an automatic or manual control that will allow shutoff when the outdoor temperature is above 40°F (4°C) so that the potential for snow or ice accumulation is negligible.
Ventilation, either natural or mechanical, shall be provided in accordance with Chapter 4 of the International Mechanical Code. Where mechanical ventilation is provided, the system shall provide the capability to reduce the outdoor air supply to the minimum required by Chapter 4 of the International Mechanical Code.

Demand control ventilation (DCV) shall be provided for spaces larger than 500 square feet (50 m2) and with an average occupant load of 25 people per 1000 square feet (93 m2) of floor area (as established in Table 403.3 of the International Mechanical Code) and served by systems with one or more of the following:

  1. An air-side economizer;
  2. Automatic modulating control of the outdoor air damper; or
  3. A design outdoor airflow greater than 3,000 cfm (1400 L/s).

Exception: Demand control ventilation is not required for systems and spaces as follows:

  1. Systems with energy recovery complying with Section C403.2.6.
  2. Multiple-zone systems without direct digital control of individual zones communicating with a central control panel.
  3. System with a design outdoor airflow less than 1,200 cfm (600 L/s).
  4. Spaces where the supply airflow rate minus any makeup or outgoing transfer air requirement is less than 1,200 cfm (600 L/s).
  5. Ventilation provided for process loads only.

Where the supply airflow rate of a fan system exceeds the values specified in Table C403.2.6, the system shall include an energy recovery system. The energy recovery system shall have the capability to provide a change in the enthalpy of the outdoor air supply of not less than 50 percent of the difference between the outdoor air and return air enthalpies, at design conditions. Where an air economizer is required, the energy recovery system shall include a bypass or controls which permit operation of the economizer as required by Section C403.4

Exception: An energy recovery ventilation system shall not be required in any of the following conditions:

  1. Where energy recovery systems are prohibited by the International Mechanical Code.
  2. Laboratory fume hood systems that include at least one of the following features:

    1. 2.1. Variable-air-volume hood exhaust and room supply systems capable of reducing exhaust and makeup air volume to 50 percent or less of design values.
    2. 2.2. Direct makeup (auxiliary) air supply equal to at least 75 percent of the exhaust rate, heated no warmer than 2°F (1.1°C) above room setpoint, cooled to no cooler than 3°F (1.7°C) below room setpoint, no humidification added, and no simultaneous heating and cooling used for dehumidification control.
  3. Systems serving spaces that are heated to less than 60°F (15.5°C) and are not cooled.
  4. Where more than 60 percent of the outdoor heating energy is provided from site-recovered or site solar energy.
  5. Heating energy recovery in Climate Zones 1 and 2.
  6. Cooling energy recovery in Climate Zones 3C, 4C, 5B, 5C, 6B, 7 and 8.
  7. Systems requiring dehumidification that employ energy recovery in series with the cooling coil.
  8. Where the largest source of air exhausted at a single location at the building exterior is less than 75 percent of the design outdoor air flow rate.
  9. Systems expected to operate less than 20 hours per week at the outdoor air percentage covered by Table C403.2.6

TABLE C403.2.6

ENERGY RECOVERY REQUIREMENT

CLIMATE ZONEPERCENT (%) OUTDOOR AIR AT FULL DESIGN AIRFLOW RATE
≥ 30% and < 40%≥ 40% and < 50%≥ 50% and < 60%≥ 60% and < 70%≥ 70% and < 80%≥ 80%
DESIGN SUPPLY FAN AIRFLOW RATE (cfm)
3B, 3C, 4B, 4C, 5BNRNRNRNR≥ 5000≥ 5000
1B, 2B, 5CNRNR≥ 26000≥ 12000≥ 5000≥ 4000
6B≥ 11000≥ 5500≥ 4500≥ 3500≥ 2500≥ 1500
1A, 2A, 3A, 4A, 5A, 6A≥ 5500≥ 4500≥ 3500≥ 2000≥ 1000> 0
7, 8≥ 2500≥ 1000> 0> 0> 0> 0

NR = not required

All supply and return air ducts and plenums shall be insulated with a minimum of R-6 insulation where located in unconditioned spaces and a minimum of R-8 insulation where located outside the building. Where located within a building envelope assembly, the duct or plenum shall be separated from the building exterior or unconditioned or exempt spaces by a minimum of R-8 insulation.

Exceptions:

  1. Where located within equipment.
  2. Where the design temperature difference between the interior and exterior of the duct or plenum does not exceed 15°F (8°C).

All ducts, air handlers and filter boxes shall be sealed. Joints and seams shall comply with Section 603.9 of the International Mechanical Code.

Ductwork shall be constructed and erected in accordance with the International Mechanical Code.

All longitudinal and transverse joints, seams and connections of supply and return ducts operating at a static pressure less than or equal to 2 inches water gauge (w.g.) (500 Pa) shall be securely fastened and sealed with welds, gaskets, mastics (adhesives), mastic-plusembedded-fabric systems or tapes installed in accordance with the manufacturer’s installation instructions. Pressure classifications specific to the duct system shall be clearly indicated on the construction documents in accordance with the International Mechanical Code.

Exception: Continuously welded and lockingtype longitudinal joints and seams on ducts operating at static pressures less than 2 inches water gauge (w.g.) (500 Pa) pressure classification.

All ducts and plenums designed to operate at a static pressure greater than 2 inches water gauge (w.g.) (500 Pa) but less than 3 inches w.g. (750 Pa) shall be insulated and sealed in accordance with Section C403.2.7. Pressure classifications specific to the duct system shall be clearly indicated on the construction documents in accordance with the International Mechanical Code.

Ducts designed to operate at static pressures in excess of 3 inches water gauge (w.g.) (750 Pa) shall be insulated and sealed in accordance with Section C403.2.7. In addition, ducts and plenums shall be leak-tested in accordance with the SMACNA HVAC Air Duct Leakage Test Manual with the rate of air leakage (CL) less than or equal to 6.0 as determined in accordance with Equation C4-5.

(Equation C4-5)

where:

F=The measured leakage rate in cfm per 100 square feet of duct surface.
P=The static pressure of the test.

Documentation shall be furnished by the designer demonstrating that representative sections totaling at least 25 percent of the duct area have been tested and that all tested sections meet the requirements of this section.

All piping serving as part of a heating or cooling system shall be thermally insulated in accordance with Table C403.2.8.

Exceptions:

  1. Factory-installed piping within HVAC equipment tested and rated in accordance with a test procedure referenced by this code.
  2. Factory-installed piping within room fan-coils and unit ventilators tested and rated according to AHRI 440 (except that the sampling and variation provisions of Section 6.5 shall not apply) and 840, respectively.
  3. Piping that conveys fluids that have a design operating temperature range between 60°F (15°C) and 105°F (41°C).
  4. Piping that conveys fluids that have not been heated or cooled through the use of fossil fuels or electric power.
  5. Strainers, control valves, and balancing valves associated with piping 1 inch (25 mm) or less in diameter.
  6. Direct buried piping that conveys fluids at or below 60°F (15°C)

TABLE C403.2.8

MINIMUM PIPE INSULATION THICKNESS (thickness in inches)a

FLUID OPERATING TEMPERATURE
RANGE AND USAGE (°F)
INSULATION CONDUCTIVITYNOMINAL PIPE OR TUBE SIZE (inches)
Conductivity
Btu • in./(h • ft
2 • °F)b
Mean Rating
Temperature, °F
< 11 to < 11/211/2 to < 44 to < 8≤ 8
> 3500.32 – 0.342504.55.05.05.05.0
251 – 3500.29 – 0.322003.04.04.54.54.5
201 – 2500.27 – 0.301502.52.52.53.03.0
141 – 2000.25 – 0.291251.51.52.02.02.0
105 – 1400.21 – 0.281001.01.01.51.51.5
40 – 600.21 – 0.27750.50.51.01.01.0
< 400.20 – 0.26750.51.01.01.01.5
  1. For piping smaller than 11/2 inch (38 mm) and located in partitions within conditioned spaces, reduction of these thicknesses by 1 inch (25 mm) shall be permitted (before thickness adjustment required in footnote b) but not to a thickness less than 1 inch (25 mm).
  2. For insulation outside the stated conductivity range, the minimum thickness (T) shall be determined as follows:

    T = r{(1 + t/r)K/k - 1}

    where:

    T=minimum insulation thickness,
    r=actual outside radius of pipe,
    t=insulation thickness listed in the table for applicable fluid temperature and pipe size,
    K=conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature (Btu × in/h × ft2 × °F) and
    k=the upper value of the conductivity range listed in the table for the applicable fluid temperature.
  3. For direct-buried heating and hot water system piping, reduction of these thicknesses by 11/2 inches (38 mm) shall be permitted (before thickness adjustment required in footnote b but not to thicknesses less than 1 inch (25 mm).
Piping insulation exposed to weather shall be protected from damage, including that due to sunlight, moisture, equipment maintenance and wind, and shall provide shielding from solar radiation that can cause degradation of the material. Adhesives tape shall not be permitted.

Mechanical systems shall be commissioned and completed in accordance with Section C408.2.

Each HVAC system having a total fan system motor nameplate horsepower (hp) exceeding 5 horsepower (hp) (3.7 kW) shall meet the provisions of Sections C403.2.10.1 through C403.2.10.2.

Each HVAC system at fan system design conditions shall not exceed the allowable fan system motor nameplate hp (Option 1) or fan system bhp (Option 2) as shown in Table C403.2.10.1(1). This includes supply fans, return/relief fans, and fan-powered terminal units associated with systems providing heating or cooling capability. Single zone variable-air-volume systems shall comply with the constant volume fan power limitation.

Exception: The following fan systems are exempt from allowable fan floor horsepower requirement.

  1. Hospital, vivarium and laboratory systems that utilize flow control devices on exhaust and/or return to maintain space pressure relationships necessary for occupant health and safety or environmental control shall be permitted to use variable volume fan power limitation.
  2. Individual exhaust fans with motor nameplate horsepower of 1 hp or less.

TABLE C403.2.10.1(1)

FAN POWER LIMITATION

LIMITCONSTANT VOLUMEVARIABLE VOLUME
Option 1: Fan system motor nameplate hpAllowable nameplate motor hphp ≤ CFMS × 0.0011hp ≤ CFMS × 0.0015
Option 2: Fan system bhpAllowable fan system bhpbhp ≤ CFMS × 0.00094 + Abhp ≤ CFMS× 0.0013 + A

where:

CFMS=The maximum design supply airflow rate to conditioned spaces served by the system in cubic feet per minute.
hp=The maximum combined motor nameplate horsepower.
Bhp=The maximum combined fan brake horsepower.
A=Sum of [PD × CFMD / 4131]

For SI: 1 cfm = 0.471 L/s.

where:

PD=Each applicable pressure drop adjustment from Table C403.2.10.1(2) in. w.c.
CFMD=The design airflow through each applicable device from Table C403.2.10.1(2) in cubic feet per minute.

For SI: 1 bhp = 735.5 W, 1 hp = 745.5 W.

TABLE C403.2.10.1(2)

FAN POWER LIMITATION PRESSURE DROP ADJUSTMENT

DEVICEADJUSTMENT
Credits
Fully ducted return and/or exhaust air systems0.5 inch w.c. (2.15 in w.c. for laboratory and vivarium systems)
Return and/or exhaust air flow control devices0.5 inch w.c.
Exhaust filters, scrubbers, or other exhaust treatment.The pressure drop of device calculated at fan system design condition
Particulate filtration credit: MERV 9 thru 120.5 inch w.c.
Particulate filtration credit: MERV 13 thru 150.9 inch. w.c.
Particulate filtration credit: MERV 16 and greater and electronically enhanced filtersPressure drop calculated at 2x clean filter pressure drop at fan system design condition.
Carbon and other gas-phase air cleanersClean filter pressure drop at fan system design condition.
Biosafety cabinetPressure drop of device at fan system design condition.
Energy recovery device, other than coil runaround loop(2.2 × energy recovery effectiveness) – 0.5 inch w.c. for each airstream
Coil runaround loop0.6 inch w.c. for each airstream
Evaporative humidifier/cooler in series with another cooling coilPressure drop of device at fan system design conditions
Sound attenuation section0.15 inch w.c.
Exhaust system serving fume hoods0.35 inch w.c.
Laboratory and vivarium exhaust systems in high-rise buildings0.25 inch w.c./100 feet of vertical duct exceeding 75 feet

w.c. = water column

For SI: 1 inch w.c. = 249 Pa, 1 inch = 25.4 mm.

For each fan, the selected fan motor shall be no larger than the first available motor size greater than the brake horsepower (bhp). The fan brake horsepower (bhp) shall be indicated on the design documents to allow for compliance verification by the code official.

Exceptions:

  1. For fans less than 6 bhp (4413 W), where the first available motor larger than the brake horsepower has a nameplate rating within 50 percent of the bhp, selection of the next larger nameplate motor size is allowed.
  2. For fans 6 bhp (4413 W) and larger, where the first available motor larger than the bhp has a nameplate rating within 30 percent of the bhp, selection of the next larger nameplate motor size is allowed.

Systems installed to provide heat outside a building shall be radiant systems.

Such heating systems shall be controlled by an occupancy sensing device or a timer switch, so that the system is automatically deenergized when no occupants are present.

This section applies to buildings served by unitary or packaged HVAC equipment listed in Tables C403.2.3(1) through C403.2.3(8), each serving one zone and controlled by a single thermostat in the zone served. It also applies to twopipe heating systems serving one or more zones, where no cooling system is installed.

Each cooling system that has a fan shall include either an air or water economizer meeting the requirements of Sections C403.3.1.1 through C403.3.1.1.4.

Exception: Economizers are not required for the systems listed below.

  1. Individual fan-cooling units with a supply capacity less than the minimum listed in Table C403.3.1(1).
  2. Where more than 25 percent of the air designed to be supplied by the system is to spaces that aredesigned to be humidified above 35°F (1.7 °C) dew-point temperature to satisfy process needs.
  3. Systems that serve residential spaces where the system capacity is less than five times the requirement listed in Table C403.3.1(1).
  4. Systems expected to operate less than 20 hours per week.
  5. Where the use of outdoor air for cooling will affect supermarket open refrigerated casework systems.
  6. Where the cooling efficiency meets or exceeds the efficiency requirements in Table C403.3.1(2).

TABLE C403.3.1(1)

ECONOMIZER REQUIREMENTS

CLIMATE ZONESECONOMIZER REQUIREMENT
1A, 1BNo requirement
2A, 2B, 3A, 3B, 3C, 4A, 4B, 4C, 5A, 5B, 5C, 6A, 6B, 7, 8Economizers on all cooling
systems ≥ 33,000 Btu/ha

For SI:1 British thermal unit per hour = 0.2931 W.

  1. The total capacity of all systems without economizers shall not exceed 300,000 Btu/h per building, or 20 percent of its air economizer capacity, whichever is greater.

TABLE C403.3.1(2)

EQUIPMENT EFFICIENCY PERFORMANCE EXCEPTION FOR ECONOMIZERS

CLIMATE
ZONES
COOLING EQUIPMENT PERFORMANCE
IMPROVEMENT (EER OR IPLV)
2B10% Efficiency Improvement
3B15% Efficiency Improvement
4B20% Efficiency Improvement
Air economizers shall comply with Sections C403.3.1.1.1 through C403.3.1.1.4.
Air economizer systems shall be capable of modulating outdoor air and return air dampers to provide up to 100 percent of the design supply air quantity as outdoor air for cooling.

Economizer dampers shall be capable of being sequenced with the mechanical cooling equipment and shall not be controlled by only mixed air temperature.

Exception: The use of mixed air temperature limit control shall be permitted for systems controlled from space temperature (such as single zone systems).

Air economizers shall be capable of automatically reducing outdoor air intake to the design minimum outdoor air quantity when outdoor air intake will no longer reduce cooling energy usage. High-limit shutoff control types for specific climates shall be chosen from Table C403.3.1.1.3(1). High-limit shutoff control settings for these control types shall be those specified in Table C403.3.1.1.3(2).

TABLE C403.3.1.1.3(1)

HIGH-LIMIT SHUTOFF CONTROL OPTIONS FOR AIR ECONOMIZERS

CLIMATE ZONESALLOWED CONTROL TYPESPROHIBITED CONTROL TYPES
1B, 2B, 3B, 3C, 4B, 4C, 5B, 5C, 6B, 7, 8Fixed dry bulb
Differential dry bulb
Electronic enthalpya
Differential enthalpy
Dew-point and dry-bulb temperatures
Fixed enthalpy
1A, 2A, 3A, 4AFixed dry bulb
Fixed enthalpy
Electronic enthalpya
Differential enthalpy
Dew-point and dry-bulb temperatures
Differential dry bulb
All other climatesFixed dry bulb
Differential dry bulb
Fixed enthalpy
Electronic enthalpya
Differential enthalpy
Dew-point and dry-bulb temperatures
  1. Electronic enthalpy controllers are devices that use a combination of humidity and dry-bulb temperature in their switching algorithm.

TABLE C403.3.1.1.3(2)

HIGH-LIMIT SHUTOFF CONTROL SETTING FOR AIR ECONOMIZERS

DEVICE TYPECLIMATE ZONEREQUIRED HIGH LIMIT
(ECONOMIZER OFF WHEN):
Fixed dry bulb1B, 2B, 3B, 3C, 4B, 4C, 5B,
5C, 6B, 7, 8
EQUATIONDESCRIPTION
TOA > 75°FOutdoor air temperature exceeds 75°F
5A, 6A, 7ATOA > 70°FOutdoor air temperature exceeds 70°F
All other zonesTOA > 65°FOutdoor air temperature exceeds 65°F
Differential dry bulb1B, 2B, 3B, 3C, 4B, 4C, 5A,
5B, 5C, 6A, 6B, 7, 8
TOA > TRAOutdoor air temperature exceeds
return air temperature
Fixed enthalpyAllhOA > 28 Btu/lbaOutdoor air enthalpy exceeds
28 Btu/lb of dry aira
Electronic EnthalpyAll(TOA, RHOA) > AOutdoor air temperature/RH exceeds the
“A” setpoint curveb
Differential enthalpyAllhOA > hRAOutdoor air enthalpy exceeds
return air enthalpy
Dew-point and dry bulb
temperatures
AllDPOA > 55°F or TOA > 75°FOutdoor air dry bulb exceeds 75°F or outside
dew point exceeds 55°F (65 gr/lb)

For SI: °C = (°F - 32) × 5/9, 1 Btu/lb = 2.33 kJ/kg.

  1. At altitudes substantially different than sea level, the Fixed Enthalpy limit shall be set to the enthalpy value at 75°F and 50-percent relative humidity. As an example, at approximately 6,000 feet elevation the fixed enthalpy limit is approximately 30.7 Btu/lb.
  2. Setpoint “A” corresponds to a curve on the psychometric chart that goes through a point at approximately 75°F and 40-percent relative humidity and is nearly parallel to dry-bulb lines at low humidity levels and nearly parallel to enthalpy lines at high humidity levels.
Systems shall be capable of relieving excess outdoor air during air economizer operation to prevent over-pressurizing the building. The relief air outlet shall be located to avoid recirculation into the building.
Hydronic systems of at least 300,000 Btu/h (87 930 W) design output capacity supplying heated and chilled water to comfort conditioning systems shall include controls that meet the requirements of Section C403.4.3.
This section applies to buildings served by HVAC equipment and systems not covered in Section C403.3.
Economizers shall comply with Sections C403.4.1.1 through C403.4.1.4.

Water economizer systems shall be capable of cooling supply air by indirect evaporation and providing up to 100 percent of the expected system cooling load at outdoor air temperatures of 50°F dry bulb (10°C dry bulb)/45°F wet bulb (7.2°C wet bulb) and below.

Exception: Systems in which a water economizer is used and where dehumidification requirements cannot be met using outdoor air temperatures of 50°F dry bulb (10°C dry bulb)/45°F wet bulb (7.2°C wet bulb) shall satisfy 100 percent of the expected system cooling load at 45°F dry bulb (7.2°C dry bulb)/ 40°F wet bulb (4.5°C wet bulb).

Precooling coils and water-to-water heat exchangers used as part of a water economizer system shall either have a waterside pressure drop of less than 15 feet (4572 mm) of water or a secondary loop shall be created so that the coil or heat exchanger pressure drop is not seen by the circulating pumps when the system is in the normal cooling (noneconomizer) mode.

Economizer systems shall be integrated with the mechanical cooling system and be capable of providing partial cooling even where additional mechanical cooling is required to meet the remainder of the cooling load.

Exceptions:

  1. Direct expansion systems that include controls that reduce the quantity of outdoor air required to prevent coil frosting at the lowest step of compressor unloading, provided this lowest step is no greater than 25 percent of the total system capacity.
  2. Individual direct expansion units that have a rated cooling capacity less than 54,000 Btu/h (15 827 W) and use nonintegrated economizer controls that preclude simultaneous operation of the economizer and mechanical cooling.

HVAC system design and economizer controls shall be such that economizer operation does not increase the building heating energy use during normal operation.

Exception: Economizers on VAV systems that cause zone level heating to increase due to a reduction in supply air temperature.

Individual VAV fans with motors of 7.5 horsepower (5.6 kW) or greater shall be:

  1. Driven by a mechanical or electrical variable speed drive;
  2. Driven by a vane-axial fan with variable-pitch blades; or
  3. The fan shall have controls or devices that will result in fan motor demand of no more than 30 percent of their design wattage at 50 percent of design airflow when static pressure set point equals one-third of the total design static pressure, based on manufacturer’s certified fan data.
Static pressure sensors used to control VAV fans shall be placed in a position such that the controller setpoint is no greater than one-third the total design fan static pressure, except for systems with zone reset control complying with Section C403.4.2.2. For sensors installed down-stream of major duct splits, at least one sensor shall be located on each major branch to ensure that static pressure can be maintained in each branch.
For systems with direct digital control of individual zone boxes reporting to the central control panel, the static pressure set point shall be reset based on the zone requiring the most pressure, i.e., the set point is reset lower until one zone damper is nearly wide open.
The heating of fluids that have been previously mechanically cooled and the cooling of fluids that have been previously mechanically heated shall be limited in accordance with Sections C403.4.3.1 through C403.4.3.3. Hydronic heating systems comprised of multiple-packaged boilers and designed to deliver conditioned water or steam into a common distribution system shall include automatic controls capable of sequencing operation of the boilers. Hydronic heating systems comprised of a single boiler and greater than 500,000 Btu/h (146 550 W) input design capacity shall include either a multistaged or modulating burner.
Hydronic systems that use a common return system for both hot water and chilled water are prohibited.
Systems that use a common distribution system to supply both heated and chilled water shall be designed to allow a dead band between changeover from one mode to the other of at least 15°F (8.3°C) outside air temperatures; be designed to and provided with controls that will allow operation in one mode for at least 4 hours before changing over to the other mode; and be provided with controls that allow heating and cooling supply temperatures at the changeover point to be no more than 30°F (16.7°C) apart.
Hydronic heat pump systems shall comply with Sections C403.4.3.3.1 through C403.4.3.3.3.

Hydronic heat pumps connected to a common heat pump water loop with central devices for heat rejection and heat addition shall have controls that are capable of providing a heat pump water supply temperature dead band of at least 20°F (11.1°C) between initiation of heat rejection and heat addition by the central devices.

Exception: Where a system loop temperature optimization controller is installed and can determine the most efficient operating temperature based on realtime conditions of demand and capacity, dead bands of less than 20°F (11°C) shall be permitted.

Heat rejection equipment shall comply with Sections C403.4.3.3.2.1 and C403.4.3.3.2.2.

Exception: Where it can be demonstrated that a heat pump system will be required to reject heat throughout the year.

For Climate Zones 3 and 4:

  1. If a closed-circuit cooling tower is used directly in the heat pump loop, either an automatic valve shall be installed to bypass all but a minimal flow of water around the tower, or lower leakage positive closure dampers shall be provided.
  2. If an open-circuit tower is used directly in the heat pump loop, an automatic valve shall be installed to bypass all heat pump water flow around the tower.
  3. If an open- or closed-circuit cooling tower is used in conjunction with a separate heat exchanger to isolate the cooling tower from the heat pump loop, then heat loss shall be controlled by shutting down the circulation pump on the cooling tower loop.
For Climate Zones 5 through 8, if an open- or closed-circuit cooling tower is used, then a separate heat exchanger shall be provided to isolate the cooling tower from the heat pump loop, and heat loss shall be controlled by shutting down the circulation pump on the cooling tower loop and providing an automatic valve to stop the flow of fluid.
Each hydronic heat pump on the hydronic system having a total pump system power exceeding 10 horsepower (hp) (7.5 kW) shall have a two-position valve.

Hydronic systems greater than or equal to 300,000 Btu/h (87 930 W) in design output capacity supplying heated or chilled water to comfort conditioning systems shall include controls that have the capability to:

  1. Automatically reset the supply-water temperatures using zone-return water temperature, building-return water temperature, or outside air temperature as an indicator of building heating or cooling demand. The temperature shall be capable of being reset by at least 25 percent of the design supply-to-return water temperature difference; or
  2. Reduce system pump flow by at least 50 percent of design flow rate utilizing adjustable speed drive(s) on pump(s), or multiple-staged pumps where at least one-half of the total pump horsepower is capable of being automatically turned off or control valves designed to modulate or step down, and close, as a function of load, or other approved means.

Chilled water plants including more than one chiller shall have the capability to reduce flow automatically through the chiller plant when a chiller is shut down. Chillers piped in series for the purpose of increased temperature differential shall be considered as one chiller.

Boiler plants including more than one boiler shall have the capability to reduce flow automatically through the boiler plant when a boiler is shut down.

Each fan powered by a motor of 7.5 hp (5.6 kW) or larger shall have the capability to operate that fan at two-thirds of full speed or less, and shall have controls that automatically change the fan speed to control the leaving fluid temperature or condensing temperature/pressure of the heat rejection device.

Exception: Factory-installed heat rejection devices within HVAC equipment tested and rated in accordance with Tables C403.2.3(6) and C403.2.3(7).

Sections C403.4.5.1 through C403.4.5.4 shall apply to complex mechanical systems serving multiple zones. Supply air systems serving multiple zones shall be VAV systems which, during periods of occupancy, are designed and capable of being controlled to reduce primary air supply to each zone to one of the following before reheating, recooling or mixing takes place:

  1. Thirty percent of the maximum supply air to each zone.
  2. Three hundred cfm (142 L/s) or less where the maximum flow rate is less than 10 percent of the total fan system supply airflow rate.
  3. The minimum ventilation requirements of Chapter 4 of the International Mechanical Code.

Exception: The following define where individual zones or where entire air distribution systems are exempted from the requirement for VAV control:

  1. Zones where special pressurization relationships or cross-contamination requirements are such that VAV systems are impractical.
  2. Zones or supply air systems where at least 75 percent of the energy for reheating or for providing warm air in mixing systems is provided from a site-recovered or site-solar energy source.
  3. Zones where special humidity levels are required to satisfy process needs.
  4. Zones with a peak supply air quantity of 300 cfm (142 L/s) or less and where the flow rate is less than 10 percent of the total fan system supply airflow rate.
  5. Zones where the volume of air to be reheated, recooled or mixed is no greater than the volume of outside air required to meet the minimum ventilation requirements of Chapter 4 of the International Mechanical Code.
  6. Zones or supply air systems with thermostatic and humidistatic controls capable of operating in sequence the supply of heating and cooling energy to the zones and which are capable of preventing reheating, recooling, mixing or simultaneous supply of air that has been previously cooled, either mechanically or through the use of economizer systems, and air that has been previously mechanically heated.
Single duct VAV systems shall use terminal devices capable of reducing the supply of primary supply air before reheating or recooling takes place.
Systems that have one warm air duct and one cool air duct shall use terminal devices which are capable of reducing the flow from one duct to a minimum before mixing of air from the other duct takes place.
Individual dual duct or mixing heating and cooling systems with a single fan and with total capacities greater than 90,000 Btu/h [(26 375 W) 7.5 tons] shall not be equipped with air economizers.

Multiple zone HVAC systems shall include controls that automatically reset the supply-air temperature in response to representative building loads, or to outdoor air temperature. The controls shall be capable of resetting the supply air temperature at least 25 percent of the difference between the design supply-air temperature and the design room air temperature.

Exceptions:

  1. Systems that prevent reheating, recooling or mixing of heated and cooled supply air.
  2. Seventy five percent of the energy for reheating is from site-recovered or site solar energy sources.
  3. Zones with peak supply air quantities of 300 cfm (142 L/s) or less.

Condenser heat recovery shall be installed for heating or reheating of service hot water provided the facility operates 24 hours a day, the total installed heat capacity of water-cooled systems exceeds 6,000,000 Btu/hr (1 758 600 W) of heat rejection, and the design service water heating load exceeds 1,000,000 Btu/h (293 100 W).

The required heat recovery system shall have the capacity to provide the smaller of:

  1. Sixty percent of the peak heat rejection load at design conditions; or
  2. The preheating required to raise the peak service hot water draw to 85°F (29°C).

Exceptions:

  1. Facilities that employ condenser heat recovery for space heating or reheat purposes with a heat recovery design exceeding 30 percent of the peak water-cooled condenser load at design conditions.
  2. Facilities that provide 60 percent of their service water heating from site solar or site recovered energy or from other sources.

Cooling systems shall not use hot gas bypass or other evaporator pressure control systems unless the system is designed with multiple steps of unloading or continuous capacity modulation. The capacity of the hot gas bypass shall be limited as indicated in Table C403.4.7

Exception: Unitary packaged systems with cooling capacities not greater than 90,000 Btu/h (26 379 W).

TABLE C403.4.7

MAXIMUM HOT GAS BYPASS CAPACITY

RATED CAPACITYMAXIMUM HOT GAS BYPASS CAPACITY
(% of total capacity)
≤ 240,000 Btu/h50
> 240,000 Btu/h25

For SI: 1 British thermal unit per hour = 0.2931 W.

This section covers the minimum efficiency of, and controls for, service water-heating equipment and insulation of service hot water piping.

Water-heating equipment and hot water storage tanks shall meet the requirements of Table C404.2. The efficiency shall be verified through data furnished by the manufacturer or through certification under an approved certification program.

TABLE C404.2

MINIMUM PERFORMANCE OF WATER-HEATING EQUIPMENT

EQUIPMENT TYPESIZE CATEGORY
(input)
SUBCATEGORY OR
RATING CONDITION
PERFORMANCE
REQUIREDa, b
TEST
PROCEDURE
Water heaters,
electric
≤ 12 kWResistance0.97 - 0.00 132V, EFDOE 10 CFR Part 430
> 12 kWResistance1.73V+ 155 SL, Btu/hANSI Z21.10.3
≤ 24 amps and
≤ 250 volts
Heat pump0.93 - 0.00 132V, EFDOE 10 CFR Part 430
Storage water heaters,
gas
≤ 75,000 Btu/h≥ 20 gal0.67 - 0.0019V, EFDOE 10 CFR Part 430
> 75,000 Btu/h and
≤ 155,000 Btu/h
< 4,000 Btu/h/galANSI Z21.10.3
> 155,000 Btu/h< 4,000 Btu/h/gal
Instantaneous
water heaters,
gas
> 50,000 Btu/h and
< 200,000 Btu/hc
≥ 4,000 (Btu/h)/gal
and < 2 gal
0.62 - 0.00 19V, EFDOE 10 CFR Part 430
≥ 200,000 Btu/h≥ 4,000 Btu/h/gal
and < 10 gal
80%EtANSI Z21.10.3
≥ 200,000 Btu/h≥ 4,000 Btu/h/gal and
≥ 10 gal
Storage water heaters,
oil
≤ 105,000 Btu/h≥ 20 gal0.59 - 0.0019V, EFDOE 10 CFR Part 430
≥ 105,000 Btu/h< 4,000 Btu/h/galANSI Z21.10.3
Instantaneous
water heaters,
oil
≤ 210,000 Btu/h≥ 4,000 Btu/h/gal and
< 2 gal
0.59 - 0.0019V, EFDOE 10 CFR Part 430
> 210,000 Btu/h≥ 4,000 Btu/h/gal and
< 10 gal
80%EtANSI Z21.10.3
> 210,000 Btu/h≥ 4,000 Btu/h/gal and
≥ 10 gal
Hot water supply boilers,
gas and oil
≥ 300,000 Btu/h and
< 12,500,000 Btu/h
≥ 4,000 Btu/h/gal and
< 10 gal
80%EtANSI Z21.10.3
Hot water supply boilers,
gas
≥ 300,000 Btu/h and
< 12,500,000 Btu/h
≥ 4,000 Btu/h/gal and
≥ 10 gal
Hot water supply boilers,
oil
> 300,000 Btu/h and
< 12,500,000 Btu/h
> 4,000 Btu/h/gal and
> 10 gal
Pool heaters,
gas and oil
All78%EtASHRAE 146
Heat pump pool heatersAll4.0 COPAHRI 1160
Unfired storage tanksAllMinimum insulation
requirement R-12.5
(h • ft2 • °F)/Btu
(none)

For SI: °C = [(°F) - 32]/1.8, 1 British thermal unit per hour = 0.2931 W, 1 gallon = 3.785 L, 1 British thermal unit per hour per gallon = 0.078 W/L.

  1. Energy factor (EF) and thermal efficiency (Et) are minimum requirements. In the EF equation, V is the rated volume in gallons.
  2. Standby loss (SL) is the maximum Btu/h based on a nominal 70°F temperature difference between stored water and ambient requirements. In the SL equation, Q is the nameplate input rate in Btu/h. In the SL equation for electric water heaters, V is the rated volume in gallons. In the SL equation for oil and gas water heaters and boilers, V is the rated volume in gallons.
  3. Instantaneous water heaters with input rates below 200,000 Btu/h must comply with these requirements if the water heater is designed to heat water to temperatures 180°F or higher.
Service water-heating equipment shall be provided with controls to allow a setpoint of 110°F (43°C) for equipment serving dwelling units and 90°F (32°C) for equipment serving other occupancies. The outlet temperature of lavatories in public facility rest rooms shall be limited to 110°F (43°C).
Water-heating equipment not supplied with integral heat traps and serving noncirculating systems shall be provided with heat traps on the supply and discharge piping associated with the equipment.

For automatic-circulating hot water and heat-traced systems, piping shall be insulated with not less than 1 inch (25 mm) of insulation having a conductivity not exceeding 0.27 Btu per inch/h × ft2 × °F (1.53 W per 25 mm/m2 × K). The first 8 feet (2438 mm) of piping in non-hotwater-supply temperature maintenance systems served by equipment without integral heat traps shall be insulated with 0.5 inch (12.7 mm) of material having a conductivity not exceeding 0.27 Btu per inch/h × ft2 × °F (1.53 W per 25 mm/ m2 × K).

Exception: Heat-traced piping systems shall meet the insulation thickness requirements per the manufacturer’s installation instructions. Untraced piping within a heat traced system shall be insulated with not less than 1 inch (25 mm) of insulation having a conductivity not exceeding 0.27 Btu per inch/h × ft2 × °F (1.53 W per 25 mm/m2 × K).

Circulating hot water system pumps or heat trace shall be arranged to be turned off either automatically or manually when there is limited hot water demand. Ready access shall be provided to the operating controls.
Pools and inground permanently installed spas shall comply with Sections C404.7.1 through C404.7.3.
All heaters shall be equipped with a readily accessible on-off switch that is mounted outside of the heater to allow shutting off the heater without adjusting the thermostat setting. Gas-fired heaters shall not be equipped with constant burning pilot lights.

Time switches or other control method that can automatically turn off and on heaters and pumps according to a preset schedule shall be installed on all heaters and pumps. Heaters, pumps and motors that have built in timers shall be deemed in compliance with this requirement.

Exceptions:

  1. Where public health standards require 24-hour pump operation.
  2. Where pumps are required to operate solar- and waste-heat-recovery pool heating systems.

Heated pools and inground permanently installed spas shall be provided with a vapor-retardant cover.

Exception: A vapor-retardant cover is not required for pools deriving over 70 percent of the energy for heating from site-recovered energy, such as a heat pump or solar energy source computed over an operating season.

This section covers lighting system controls, the connection of ballasts, the maximum lighting power for interior applications, electrical energy consumption, and minimum acceptable lighting equipment for exterior applications.

Exception: Dwelling units within commercial buildings shall not be required to comply with Sections C405.2 through C405.5, provided that not less than 75 percent of the permanently installed luminaires, other than low-voltage lighting, shall be fitted for, and contain only, high-efficacy lamps.

Lighting systems shall be provided with controls as specified in Sections C405.2.1, C405.2.2, C405.2.3 and C405.2.4.
All buildings shall include manual lighting controls that meet the requirements of Sections C405.2.1.1 and C405.2.1.2.

Each area enclosed by walls or floor-to-ceiling partitions shall have at least one manual control for the lighting serving that area. The required controls shall be located within the area served by the controls or be a remote switch that identifies the lights served and indicates their status.

Exceptions:

  1. Areas designated as security or emergency areas that need to be continuously lighted.
  2. Lighting in stairways or corridors that are elements of the means of egress.

Each area that is required to have a manual control shall also allow the occupant to reduce the connected lighting load in a reasonably uniform illumination pattern by at least 50 percent. Lighting reduction shall be achieved by one of the following or other approved method:

  1. Controlling all lamps or luminaires;
  2. Dual switching of alternate rows of luminaires, alternate luminaires or alternate lamps;
  3. Switching the middle lamp luminaires independently of the outer lamps; or
  4. Switching each luminaire or each lamp.

Exception: Light reduction controls need not be provided in the following areas and spaces:

  1. Areas that have only one luminaire, with rated power less than 100 watts.
  2. Areas that are controlled by an occupant-sensing device.
  3. Corridors, equipment rooms, storerooms, restrooms, public lobbies, electrical or mechanical rooms.
  4. Sleeping unit (see Section C405.2.3).
  5. Spaces that use less than 0.6 watts per square foot (6.5 W/m2).
  6. Daylight spaces complying with Section C405.2.2.3.2.

Each area that is required to have a manual control shall also have controls that meet the requirements of Sections C405.2.2.1, C405.2.2.2 and C405.2.2.3.

Exception: Additional lighting controls need not be provided in the following spaces:

  1. Sleeping units.
  2. Spaces where patient care is directly provided.
  3. Spaces where an automatic shutoff would endanger occupant safety or security.
  4. Lighting intended for continuous operation.

Automatic time switch controls shall be installed to control lighting in all areas of the building.

Exceptions:

  1. Emergency egress lighting does not need to be controlled by an automatic time switch.
  2. Lighting in spaces controlled by occupancy sensors does not need to be controlled by automatic time switch controls.

The automatic time switch control device shall include an override switching device that complies with the following:

  1. The override switch shall be in a readily accessible location;
  2. The override switch shall be located where the lights controlled by the switch are visible; or the switch shall provide a mechanism which announces the area controlled by the switch;
  3. The override switch shall permit manual operation;
  4. The override switch, when initiated, shall permit the controlled lighting to remain on for a maximum of 2 hours; and
  5. Any individual override switch shall control the lighting for a maximum area of 5,000 square feet (465 m2).

Exception: Within malls, arcades, auditoriums, single tenant retail spaces, industrial facilities and arenas:

  1. The time limit shall be permitted to exceed 2 hours provided the override switch is a captive key device; and
  2. The area controlled by the override switch is permitted to exceed 5,000 square feet (465 m2), but shall not exceed 20,000 square feet (1860 m2).

Occupancy sensors shall be installed in all classrooms, conference/meeting rooms, employee lunch and break rooms, private offices, restrooms, storage rooms and janitorial closets, and other spaces 300 square feet (28 m2) or less enclosed by floor-to-ceiling height partitions. These automatic control devices shall be installed to automatically turn off lights within 30 minutes of all occupants leaving the space, and shall either be manual on or shall be controlled to automatically turn the lighting on to not more than 50 percent power.

Exception: Full automatic-on controls shall be permitted to control lighting in public corridors, stairways, restrooms, primary building entrance areas and lobbies, and areas where manual-on operation would endanger the safety or security of the room or building occupants

Daylight zones shall be designed such that lights in the daylight zone are controlled independently of general area lighting and are controlled in accordance with either Section C405.2.2.3.1 or Section C405.2.2.3.2. Each daylight control zone shall not exceed 2,500 square feet (232 m2). Contiguous daylight zones adjacent to vertical fenestration are allowed to be controlled by a single controlling device provided that they do not include zones facing more than two adjacent cardinal orientations (i.e., north, east, south, west). Daylight zones under skylights more than 15 feet (4572 mm) from the perimeter shall be controlled separately from daylight zones adjacent to vertical fenestration.

Exception: Daylight zones enclosed by walls or ceiling height partitions and containing two or fewer light fixtures are not required to have a separate switch for general area lighting.

Manual controls shall be installed in daylight zones unless automatic controls are installed in accordance with Section C405.2.2.3.2.

Set-point and other controls for calibrating the lighting control device shall be readily accessible.

Daylighting controls device shall be capable of automatically reducing the lighting power in response to available daylight by either one of the following methods:

  1. Continuous dimming using dimming ballasts and daylight-sensing automatic controls that are capable of reducing the power of general lighting in the daylit zone continuously to less than 35 percent of rated power at maximum light output.
  2. Stepped dimming using multi-level switching and daylight-sensing controls that are capable of reducing lighting power automatically. The system shall provide a minimum of two control channels per zone and be installed in a manner such that at least one control step is between 50 percent and 70 percent of design lighting power and another control step is no greater than 35 percent of design power.
Where multi-level lighting controls are required by this code, the general lighting in the daylight zone shall be separately controlled by at least one multi-level lighting control that reduces the lighting power in response to daylight available in the space. Where the daylit illuminance in the space is greater than the rated illuminance of the general lighting of daylight zones, the general lighting shall be automatically controlled so that its power draw is no greater than 35 percent of its rated power. The multi-level lighting control shall be located so that calibration and set point adjustment controls are readily accessible and separate from the light sensor.

Specific application controls shall be provided for the following:

  1. Display and accent light shall be controlled by a dedicated control which is independent of the controls for other lighting within the room or space.
  2. Lighting in cases used for display case purposes shall be controlled by a dedicated control which is independent of the controls for other lighting within the room or space.
  3. Hotel and motel sleeping units and guest suites shall have a master control device at the main room entry that controls all permanently installed luminaires and switched receptacles.
  4. Supplemental task lighting, including permanently installed under-shelf or under-cabinet lighting, shall have a control device integral to the luminaires or be controlled by a wall-mounted control device provided the control device is readily accessible.
  5. Lighting for nonvisual applications, such as plant growth and food warming, shall be controlled by a dedicated control which is independent of the controls for other lighting within the room or space.
  6. Lighting equipment that is for sale or for demonstrations in lighting education shall be controlled by a dedicated control which is independent of the controls for other lighting within the room or space.
Lighting not designated for dusk-to-dawn operation shall be controlled by either a combination of a photosensor and a time switch, or an astronomical time switch. Lighting designated for dusk-to-dawn operation shall be controlled by an astronomical time switch or photosensor. All time switches shall be capable of retaining programming and the time setting during loss of power for a period of at least 10 hours.

The following luminaires located within the same area shall be tandem wired:

  1. Fluorescent luminaires equipped with one, three or odd-numbered lamp configurations, that are recess-mounted within 10 feet (3048 mm) center-to-center of each other.
  2. Fluorescent luminaires equipped with one, three or any odd-numbered lamp configuration, that are pendant- or surface-mounted within 1 foot (305 mm) edge-to-edge of each other.

Exceptions:

  1. Where electronic high-frequency ballasts are used.
  2. Luminaires on emergency circuits.
  3. Luminaires with no available pair in the same area.
Internally illuminated exit signs shall not exceed 5 watts per side.
A building complies with this section if its total connected lighting power calculated under Section C405.5.1 is no greater than the interior lighting power calculated under Section C405.5.2.

The total connected interior lighting power (watts) shall be the sum of the watts of all interior lighting equipment as determined in accordance with Sections C405.5.1.1 through C405.5.1.4.

Exceptions:

  1. The connected power associated with the following lighting equipment is not included in calculating total connected lighting power.

    1. 1.1. Professional sports arena playing field lighting.
    2. 1.2. Sleeping unit lighting in hotels, motels, boarding houses or similar buildings.
    3. 1.3. Emergency lighting automatically off during normal building operation.
    4. 1.4. Lighting in spaces specifically designed for use by occupants with special lighting needs including the visually impaired visual impairment and other medical and age-related issues.
    5. 1.5. Lighting in interior spaces that have been specifically designated as a registered interior historic landmark.
    6. 1.6. Casino gaming areas.
  2. Lighting equipment used for the following shall be exempt provided that it is in addition to general lighting and is controlled by an independent control device:

    1. 2.1. Task lighting for medical and dental purposes.
    2. 2.2. Display lighting for exhibits in galleries, museums and monuments.
  3. Lighting for theatrical purposes, including performance, stage, film production and video production.
  4. Lighting for photographic processes.
  5. Lighting integral to equipment or instrumentation and is installed by the manufacturer.
  6. Task lighting for plant growth or maintenance.
  7. Advertising signage or directional signage.
  8. In restaurant buildings and areas, lighting for food warming or integral to food preparation equipment.
  9. Lighting equipment that is for sale.
  10. Lighting demonstration equipment in lighting education facilities.
  11. Lighting approved because of safety or emergency considerations, inclusive of exit lights.
  12. Lighting integral to both open and glass-enclosed refrigerator and freezer cases.
  13. Lighting in retail display windows, provided the display area is enclosed by ceiling-height partitions.
  14. Furniture mounted supplemental task lighting that is controlled by automatic shutoff.
The wattage shall be the maximum labeled wattage of the luminaire.
The wattage shall be the specified wattage of the transformer supplying the system.
The wattage of all other lighting equipment shall be the wattage of the lighting equipment verified through data furnished by the manufacturer or other approved sources.

The wattage shall be:

  1. The specified wattage of the luminaires included in the system with a minimum of 30 W/lin ft. (98 W/lin. m);
  2. The wattage limit of the system’s circuit breaker; or
  3. The wattage limit of other permanent current limiting device(s) on the system.

The total interior lighting power allowance (watts) is determined according to Table C405.5.2(1) using the Building Area Method, or Table C405.5.2(2) using the Space-by-Space Method, for all areas of the building covered in this permit. For the Building Area Method, the interior lighting power allowance is the floor area for each building area type listed in Table C405.5.2(1) times the value from Table C405.5.2(1) for that area. For the purposes of this method, an “area” shall be defined as all contiguous spaces that accommodate or are associated with a single building area type as listed in Table C405.5.2(1). Where this method is used to calculate the total interior lighting power for an entire building, each building area type shall be treated as a separate area. For the Space-by-Space Method, the interior lighting power allowance is determined by multiplying the floor area of each space times the value for the space type in Table C405.5.2(2) that most closely represents the proposed use of the space, and then summing the lighting power allowances for all spaces. Tradeoffs among spaces are permitted.

TABLE C405.5.2(1)

INTERIOR LIGHTING POWER ALLOWANCES: BUILDING AREA METHOD

BUILDING AREA TYPELPD (w/ft2)
Automotive facility0.9
Convention center1.2
Courthouse1.2
Dining: bar lounge/leisure1.3
Dining: cafeteria/fast food1.4
Dining: family1.6
Dormitory1.0
Exercise center1.0
Fire station0.8
Gymnasium1.1
Health care clinic1.0
Hospital1.2
Hotel1.0
Library1.3
Manufacturing facility1.3
Motel1.0
Motion picture theater1.2
Multifamily0.7
Museum1.1
Office0.9
Parking garage0.3
Penetentiary1.0
Performing arts theater1.6
Police station1.0
Post office1.1
Religious building1.3
Retail1.4
School/university1.2
Sports arena1.1
Town hall1.1
Transportation1.0
Warehouse0.6
Workshop1.4

TABLE C405.5.2(2)

INTERIOR LIGHTING POWER ALLOWANCES: SPACE-BY-SPACE METHOD

COMMON SPACE-BY-SPACE TYPESLPD (w/ft2)
Atrium – First 40 feet in height0.03 per ft. ht.
Atrium – Above 40 feet in height0.02 per ft. ht.
Audience/seating area - permanent
For auditorium0.9
For performing arts theater2.6
For motion picture theater1.2
Classroom/lecture/training1.30
Conference/meeting/multipurpose1.2
Corridor/transition0.7
Dining area
Bar/lounge/leisure dining1.40
Family dining area1.40
Dressing/fitting room performing arts theater1.1
Electrical/mechanical1.10
Food preparation1.20
Laboratory for classrooms1.3
Laboratory for medical/industrial/research1.8
Lobby1.10
Lobby for performing arts theater3.3
Lobby for motion picture theater1.0
Locker room0.80
Lounge recreation0.8
Office – enclosed1.1
Office – open plan1.0
Restroom1.0
Sales area1.6a
Stairway0.70
Storage0.8
Workshop1.60
Courthouse/police station/penetentiary
Courtroom1.90
Confinement cells1.1
Judge chambers1.30
Penitentiary audience seating0.5
Penitentiary classroom1.3
Penitentiary dining1.1
BUILDING SPECIFIC SPACE-BY-SPACE TYPES
Automotive – service/repair0.70
Bank/office – banking activity area1.5
Dormitory living quarters1.10
Gymnasium/fitness center
Fitness area0.9
Gymnasium audience/seating0.40
Playing area1.40
Healthcare clinic/hospital
Corridors/transition1.00
Exam/treatment1.70
Emergency2.70
Public and staff lounge0.80
Medical supplies1.40
Nursery0.9
Nurse station1.00
Physical therapy0.90
Patient room0.70
Pharmacy1.20
Radiology/imaging1.3
Operating room2.20
Recovery1.2
Lounge/recreation0.8
Laundry – washing0.60
Hotel
Dining area1.30
Guest rooms1.10
Hotel lobby2.10
Highway lodging dining1.20
Highway lodging guest rooms1.10
Library
Stacks1.70
Card file and cataloguing1.10
Reading area1.20
Manufacturing
Corridors/transition0.40
Detailed manufacturing1.3
Equipment room1.0
Extra high bay (> 50-foot floor-ceiling height)1.1
High bay (25- – 50-foot floor-ceiling height)1.20
Low bay (< 25-foot floor-ceiling height)1.2
Museum
General exhibition1.00
Restoration1.70
Parking garage – garage areas0.2
Convention center
Exhibit space1.50
Audience/seating area0.90
Fire stations
Engine room0.80
Sleeping quarters0.30
Post office0.9
Sorting area
Religious building
Fellowship hall0.60
Audience seating2.40
Worship pulpit/choir2.40
Retail
Dressing/fitting area0.9
Mall concourse1.6
Sales area1.6a
Sports arena
Audience seating0.4
Court sports area – Class 40.7
Court sports area – Class 31.2
Court sports area – Class 21.9
Court sports area – Class 13.0
Ring sports area2.7
Transportation
Air/train/bus baggage area1.00
Airport concourse0.60
Terminal – ticket counter1.50
Warehouse
Fine material storage1.40
Medium/bulky material0.60

For SI: 1 foot = 304.8 mm, 1 watt per square foot = 11 W/m2.

  1. Where lighting equipment is specified to be installed to highlight specific merchandise in addition to lighting equipment specified for general lighting and is switched or dimmed on circuits different from the circuits for general lighting, the smaller of the actual wattage of the lighting equipment installed specifically for merchandise, or additional lighting power as determined below shall be added to the interior lighting power determined in accordance with this line item.

Calculate the additional lighting power as follows:

Additional Interior Lighting Power Allowance = 500 watts + (Retail Area 1 × 0.6 W/ft2) + (Retail Area 2 × 0.6 W/ft2) + (Retail Area 3 × 1.4 W/ft2) + (Retail Area 4 × 2.5 W/ft2).

where:

Retail Area 1=The floor area for all products not listed in Retail Area 2, 3 or 4.
Retail Area 2=The floor area used for the sale of vehicles, sporting goods and small electronics.
Retail Area 3=The floor area used for the sale of furniture, clothing, cosmetics and artwork.
Retail Area 4=The floor area used for the sale of jewelry, crystal and china.

Exception: Other merchandise categories are permitted to be included in Retail Areas 2 through 4 above, provided that justification documenting the need for additional lighting power based on visual inspection, contrast, or other critical display is approved by the authority having jurisdiction.

All exterior lighting, other than low-voltage landscape lighting, shall comply with Sections C405.6.1 and C405.6.2.

Exception: Where approved because of historical, safety, signage, or emergency considerations.

All exterior building grounds luminaires that operate at greater than 100 watts shall contain lamps having a minimum efficacy of 60 lumens per watt unless the luminaire is controlled by a motion sensor or qualifies for one of the exceptions under Section C405.6.2.

The total exterior lighting power allowance for all exterior building applications is the sum of the base site allowance plus the individual allowances for areas that are to be illuminated and are permitted in Table C405.6.2(2) for the applicable lighting zone. Tradeoffs are allowed only among exterior lighting applications listed in Table C405.6.2(2), Tradable Surfaces section. The lighting zone for the building exterior is determined from Table C405.6.2(1) unless otherwise specified by the local jurisdiction. Exterior lighting for all applications (except those included in the exceptions to Section C405.6.2) shall comply with the requirements of Section C405.6.1.

Exception: Lighting used for the following exterior applications is exempt where equipped with a control device independent of the control of the nonexempt lighting:

  1. Specialized signal, directional and marker lighting associated with transportation;
  2. Advertising signage or directional signage;
  3. Integral to equipment or instrumentation and is installed by its manufacturer;
  4. Theatrical purposes, including performance, stage, film production and video production;
  5. Athletic playing areas;
  6. Temporary lighting;
  7. Industrial production, material handling, transportation sites and associated storage areas;
  8. Theme elements in theme/amusement parks; and
  9. Used to highlight features of public monuments and registered historic landmark structures or buildings.

TABLE C405.6.2(1)

EXTERIOR LIGHTING ZONES

LIGHTING ZONEDESCRIPTION
1Developed areas of national parks, state parks, forest land, and rural areas
2Areas predominantly consisting of residential zoning, neighborhood business districts, light industrial with limited nighttime use and residential mixed use areas
3All other areas
4High-activity commercial districts in major metropolitan areas as designated by the local land use planning authority

TABLE C405.6.2(2)

INDIVIDUAL LIGHTING POWER ALLOWANCES FOR BUILDING EXTERIORS

LIGHTING ZONES
Zone 1Zone 2Zone 3Zone 4
Base Site Allowance
(Base allowance is
usable in tradable or
nontradable surfaces.)
500 W600 W750 W1300 W
Tradable Surfaces
(Lighting power
densities for uncovered
parking areas, building
grounds, building
entrances and exits,
canopies and overhangs
and outdoor sales areas
are tradable.)
Uncovered Parking Areas
Parking areas and drives0.04 W/ft20.06 W/ft20.10 W/ft20.13 W/ft2
Building Grounds
Walkways less than
10 feet wide
0.7 W/linear foot0.7 W/linear foot0.8 W/linear foot1.0 W/linear foot
Walkways 10 feet wide
or greater, plaza areas
special feature areas
0.14 W/ft20.14 W/ft20.16 W/ft20.2 W/ft2
Stairways0.75 W/ft21.0 W/ft21.0 W/ft21.0 W/ft2
Pedestrian tunnels0.15 W/ft20.15 W/ft20.2 W/ft20.3 W/ft2
Building Entrances and Exits
Main entries20 W/linear foot
of door width
20 W/linear foot
of door width
30 W/linear foot
of door width
30 W/linear foot
of door width
Other doors20 W/linear foot
of door width
20 W/linear foot
of door width
20 W/linear foot
of door width
20 W/linear foot
of door width
Entry canopies0.25 W/ft20.25 W/ft20.4 W/ft20.4 W/ft2
Sales Canopies
Free-standing and
attached
0.6 W/ft20.6 W/ft20.8 W/ft21.0 W/ft2
Outdoor Sales
Open areas (including
vehicle sales lots)
0.25 W/ft20.25 W/ft20.5 W/ft20.7 W/ft2
Street frontage for
vehicle sales lots in
addition to “open area”
allowance
No allowance10 W/linear foot10 W/linear foot30 W/linear foot
Nontradable Surfaces
(Lighting power
density calculations
for the following
applications can be
used only for the
specific application
and cannot be traded
between surfaces or
with other exterior
lighting. The
following allowances
are in addition
to any allowance otherwise
permitted in the
“Tradable Surfaces”
section of this table.)
Building facadesNo allowance0.1 W/ft2 for each
illuminated wall or
surface or 2.5 W/linear
foot for each illuminated
wall or surface length
0.15 W/ft2 for each
illuminated wall or
surface or 3.75 W/linear
foot for each illuminated
wall or surface length
0.2 W/ft2 for each
illuminated wall or
surface or 5.0 W/linear
foot for each illuminated
wall or surface length
Automated teller
machines and night
depositories
270 W per location plus
90 W per additional
ATM per location
270 W per location plus
90 W per additional
ATM per location
270 W per location plus
90 W per additional
ATM per location
270 W per location plus
90 W per additional
ATM per location
Entrances and gatehouse
inspection stations at
guarded facilities
0.75 W/ft2 of covered
and uncovered area
0.75 W/ft2 of covered
and uncovered area
0.75 W/ft2 of covered
and uncovered area
0.75 W/ft2 of covered
and uncovered area
Loading areas for law
enforcement, fire,
ambulance and other
emergency service
vehicles
0.5 W/ft2 of covered and uncovered area0.5 W/ft2 of covered and uncovered area0.5 W/ft2 of covered and uncovered area0.5 W/ft2 of covered
and uncovered area
Drive-up windows/doors400 W per drive-through400 W per drive-through400 W per drive-through400 W per drive-through
Parking near 24-hour
retail entrances
800 W per main entry800 W per main entry800 W per main entry800 W per main entry

For SI: 1 foot = 304.8 mm, 1 watt per square foot = W/0.0929 m2.

In buildings having individual dwelling units, provisions shall be made to determine the electrical energy consumed by each tenant by separately metering individual dwelling units.

Buildings shall comply with at least one of the following:

  1. Efficient HVAC Performance in accordance with Section C406.2.
  2. Efficient Lighting System in accordance with Section C406.3.
  3. On-Site Supply of Renewable Energy in accordance with Section C406.4.

Individual tenant spaces shall comply with either Section C406.2 or Section C406.3 unless documentation can be provided that demonstrates compliance with Section C406.4 for the entire building.

Equipment shall meet the minimum efficiency requirements of Tables C406.2.(1) through C406.2(7) in addition to the requirements in Section C403. This section shall only be used where the equipment efficiencies in Tables C406.2(1) through C406.2(7) are greater than the equipment efficiencies listed in Table C403.2.3(1) through 403.2.3(7) for the equipment type.

TABLE C406.2(1)

UNITARY AIR CONDITIONERS AND CONDENSING UNITS, ELECTRICALLY OPERATED, EFFICIENCY REQUIREMENTS

EQUIPMENT TYPESIZE CATEGORYSUBCATEGORY OR
RATING CONDITION
MINIMUM EFFICIENCYa
CLIMATE ZONES
1 - 5
CLIMATE ZONES
6 - 8
Air conditioners,
air cooled
< 65,000 Btu/hSplit system15.0 SEER14 SEER
12.5 EER12 EER
Single package15.0 SEER14.0 SEER
12.0 EER11.6 EER
≥ 65,000 Btuh/h and
< 240,000 Btu/h
Split system and single package12.0 EERb11.5 EERb
12.54 IEERb12.0 EERbb
≥ 240,000 Btu/h and
< 760,000 Btu/h
Split system and single package10.8 EERb10.5 EERb
11.3 IEERb11.0 IEERb
≥ 760,000 Btu/h10.2 EERb9.7 EERb
10.7 IEERb10.2 IEERb
Air conditioners, water
and evaporatively cooled
Split system and single package14.0 EER14.0 EER

For SI: 1 British thermal unit per hour = 0.2931 W.

  1. IEERs are only applicable to equipment with capacity modulation.
  2. Deduct 0.2 from the required EERs and IPLVs for units with a heating section other than electric resistance heat.

TABLE C406.2(2)

UNITARY AND APPLIED HEAT PUMPS, ELECTRICALLY OPERATED, EFFICIENCY REQUIREMENTS

EQUIPMENT TYPESIZE CATEGORYSUBCATEGORY OR RATING
CONDITION
MINIMUM EFFICIENCYa
CLIMATE ZONES
1 - 5
CLIMATE ZONES
6 - 8
Air cooled
(Cooling mode)
< 65,000 Btu/hSplit system15.0 SEER,14.0 SEER,
12.5 EER12.0 EER
Single package15.0 SEER,14.0 SEER
12.0 EER11.6 EER
≥ 65,000 Btu/h and
< 240,000 Btu/h
Split system and single package12.0 SEER,11.5 EERb,
12.4 EER12.0 IEERb
≥ 240,000 Btu/hSplit system and single package12.0 SEER,10.5 EERb,
12.4 EER10.5 IEERb
Water sources
(Cooling mode)
< 135,000 Btu/h85°F entering water14.0 EER14.0 EER
Air cooled
(Heating mode)
< 65,000 Btu/h
(Cooling capacity)
Split system9.0 HSPF8.5 HSPF
Single package8.5 HSPF8.0 HSPF
≥ 65,000 Btu/h and
< 135,000 Btu/h
(Cooling capacity)
47°F db/43°F wb outdoor air3.4 COP3.4 COP
17°F db/15°F wb outdoor air2.4 COP2.4 COP
≥ 135,000 Btu/h
(Cooling capacity)
47°F db/43°F wb outdoor air3.2 COP3.2 COP
77°F db/15°F wb outdoor air2.1 COP2.1 COP
Water sources
(Heating mode)
< 135,000 Btu/h
(Cooling capacity)
70°F entering water4.6 COP4.6 COP

For SI: °C = [(°F) - 32] / 1.8, 1 British thermal unit per hour = 0.2931 W.

db = dry-bulb temperature, °F; wb = wet-bulb temperature, °F.

  1. IEERs and Part load rating conditions are only applicable to equipment with capacity modulation.
  2. Deduct 0.2 from the required EERs and IPLVs for units with a heating section other than electric resistance heat.

TABLE C406.2(3)

PACKAGED TERMINAL AIR CONDITIONERS AND PACKAGED TERMINALHEAT PUMPS

EQUIPMENT TYPESIZE CATEGORYMINIMUM EFFICIENCY
Air conditioners and heat pumps
(cooling mode)
< 7,000 Btu/h11.9 EER
7,000 Btu/h and < 10,000 Btu/h11.3 EER
10,000 Btu/h and ≤ 13,000 Btu/h10.7 EER
> 13,000 Btu/h9.5 EER

TABLE C406.2(4)

WARM AIR FURNACES AND COMBINATION WARM AIR FURNACES/AIR-CONDITIONING UNITS, WARM AIR DUCT FURNACES AND UNIT HEATERS, EFFICIENCY REQUIREMENTS

EQUIPMENT TYPESIZE CATEGORY
(INPUT)
SUBCATEGORY OR
RATING CONDITION
MINIMUM EFFICIENCYTEST PROCEDURE
Warm air furnaces,
gas fireda
< 225,000 Btu/hFor Climate Zones 1 and 2 NRDOE 10 CFR Part 430
or ANSI Z21.47
For Climate Zones 3 and 4
90 AFUE or 90 Etc
For Climate Zones 4 – 8
92 AFUE or 92 Etc
≥ 225,000 Btu/hMaximum capacity90% EcbANSI Z21.47
Warm air furnaces,
oil fireda
< 225,000 Btu/hFor Climate Zones 1 and 2 NRDOE 10 CFR Part 430
or UL 727
For Climate Zones 3 – 8
85 AFUE or 85 Etc
≥ 225,000 Btu/hMaximum capacity85% EtbUL 727
Warm air duct furnaces, gas firedaAll capacitiesMaximum capacity90% EcANSI Z83.8
Warm air unit heaters, gas firedAll capacitiesMaximum capacity90% EcANSI Z83.8
Warm air unit heaters, oil firedAll capacitiesMaximum capacity90% EcUL 731

For SI: 1 British thermal unit per hour = 0.2931 W.

Et = Thermal efficiency. Ec = Combustion efficiency (100 percent less flue losses).

  1. Efficient furnace fan: Fossil fuel furnaces in climate zones 3 to 8 shall have a furnace electricity ratio not greater than 2 percent and shall include a manufacturer’s designation of the furnace electricity ratio.
  2. Units shall also include an IID (intermittent ignition device), have jacket losses not exceeding 0.75 percent of the input rating, and have either power venting or a flue damper. A vent damper is an acceptable alternative to a flue damper for those furnaces where combustion air is drawn from the conditioned space.
  3. Where there are two ratings for units not covered by NAECA (3-phase power or cooling capacity greater than or equal to 65,000 Btu/h [19 kW]), units shall be permitted to comply with either rating.

TABLE C406.2(5)

BOILER, EFFICIENCY REQUIREMENTS

EQUIPMENT TYPEFUELSIZE CATEGORYTEST PROCEEDUREMINIMUM
EFFICIENCY
SteamGas< 300,000 Btu/hDOE 10 CFR Part 43083% AFUE
> 300,000 Btu / h and > 2.5 m Btu/hDOE 10 CFR Part 43181% Et
>2.5 m Btu/h82% Ec
Oil< 300,000 Btu/hDOE 10 CFR Part 43085% AFUE
> 300,000 Btu/h and > 2.5 m Btu/hDOE 10 CFR Part 43183% Et
>2.5 m Btu/h84% Ec
Hot waterGas< 300,000 Btu/hDOE 10 CFR Part 43097% AFUE
> 300,000 Btu/h and > 2.5 m Btu/hDOE 10 CFR Part 43197% Et
>2.5 m Btu/h94% Ec
Oil< 300,000 Btu/hDOE 10 CFR Part 43090% AFUE
> 300,000 Btu/h and > 2.5 m Btu/hDOE 10 CFR Part 43188% Et
>2.5 m Btu/h87% Ec

For SI: 1 British thermal unit per hour = 0.2931 W.

Et = Thermal efficiency. Ec = Combustion efficiency (100 percent less flue losses).

TABLE C406.2(6)

CHILLERS—EFFICIENCY REQUIREMENTS

EQUIPMENT TYPESIZE CATEGORYUNITSMINIMUM EFFICIENCYc (I-P)Test
Procedureb
Path APath Bc
Full LoadIPLVFull LoadIPLV
Air-cooled chillers with condenser, electrically operated< 150 tonsEER10.00012.500NANAAHRI 550/ 590f
≥150 tonsEER10.00012.750NANA
Air-cooled without condenser, electrical operatedAll capacitiesEERCondenserless units shall be rated with matched condensersAHRI 550/ 590f
Water-cooled, electrically operated, positive displacement (reciprocating)All capacitieskw/tonReciprocating units required to comply with water cooled positive displacement requirementsAHRI 550/ 590f
Water-cooled electrically operated, positive displacement< 75 tonskw/ton0.7800.6300.8000.600AHRI 550/590f
≥ 75 tons and
< 150 tons
kw/ton0.7750.6150.7900.586
≥ 150 tons and < 300 tonskw/ton0.6800.5800.7180.540
≥ 300 tonskw/ton0.6200.5400.6390.490
Water-cooled electrically operated, centrifugald< 150 tonskw/ton0.6340.5960.6390.450AHRI 550/590f
≥ 150 tons and < 300 tonskw/ton0.6340.5960.6390.450
≥ 300 tons and < 600 tonskw/ton0.5760.5490.6000.400
≥ 600 tonskw/ton0.5700.5390.5900.400
Air-cooled absorption single effecteAll capacitiesCOP0.600NRNANAAHRI 560
Water-cooled absorption single effecteAll capacitiesCOP0.700NRNANA
Absorption double effect indirect-firedAll capacitiesCOP1.0001.050NANA
Absorption double effect direct firedAll capacitiesCOP1.0001.000NANA

For SI: 1 Ton = 3516 W.

NA = Not applicable and cannot be used for compliance. NR = No minimum requirements.

  1. Compliance with this standard can be obtained by meeting the minimum requirements of Path A or Path B. However both the full load and IPLV shall be met to fulfill the requirements of Path A and Path B.
  2. Chapter 6 of the referenced standard contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure.
  3. Path B is intended for applications with significant operating time at part load. All Path B machines shall be equipped with demand limiting capable controls.
  4. The chiller equipment requirements do not apply for chillers used in low-temperature applications where the design leaving fluid temperature is greater than 40°F.
  5. Only allowed to be used in heat recovery applications.
  6. Packages that are not designed for operation at ARI Standard 550/590 test conditions (and, thus, cannot be tested to meet the requirements of Table C-3) of 44°F leaving chilled-water temperature and 85°F entering condenser-water temperature with 3 gpm/ton condenser-water flow shall have maximum full-load kW/ton and NPLV ratings adjusted using the following equation:

    Adjusted maximum full load kW/ton rating = (full load kW/ton from Table C-3)/Kadj

    Adjusted maximum NPLV rating = (IPLV from Table C-3)/Kadj

    where:

    Kadj=6.174722 – 0.303668(X) + 0.00629466(X)2 – 0.000045780(X)3
    X=DTstd + LIFT (°F)
    DTstd=[(24 + (full load kW/ton from Table C-3) × 6.83)]/flow (°F)
    Flow=condenser-water flow (gpm) / cooling full load capacity (tons)
    LIFT=CEWT - CLWT (°F)
    CEWT=full load entering condenser-water temperature (°F)
    CLWT=full load leaving chilled-water temperature (°F)

    The adjusted full load and NPLV values are only applicable over the following full-load design ranges:

    Minimum leaving chilled-water temperature: 38°F

    Maximum condenser entering water temperature: 102°F

    Condenser-water flow: 1 to 6 gpm/ton

    X ≥ 39°F and ≤ 60°F

TABLE C406.2(7)

ABSORPTION CHILLERS—EFFICIENCY REQUIREMENTS

EQUIPMENT TYPEMINIMUM EFFICIENCY
FULL LOAD COP (IPLV)
Air cooled, single effect0.60, allowed only in
heat recovery applications
Water cooled, single effect0.70, allowed only in
heat recovery applications
Double effect – direct fired1.0 (1.05 )
Double effect – indirect fired1.20

Whole building lighting power density (Watts/sf) shall comply with the requirements of Section C406.3.1.

TABLE C406.3

REDUCED INTERIOR LIGHTING POWER

BUILDING AREA TYPEaLPD (w/ft2)
Automotive facility0.82
Convention center1.08
Courthouse1.05
Dining: bar lounge/leisure0.99
Dining: cafeteria/fast food0.90
Dining: family0.89
Dormitory0.61
Exercise center0.88
Fire station0.71
Gymnasium1.0
Health care clinic0.87
Hospital1.10
Library1.18
Manufacturing facility1.11
Hotel/motel0.88
Motion picture theater0.83
Museum1.06
Multifamily0.60
Office0.90/0.85b
Performing arts theater1.39
Police station0.96
Post office0.87
Religious building1.05
Retail1.4/1.3b
School/ university0.99
Sports arena0.78
Town hall0.92
Transportation0.77
Warehousec0.6
Workshop1.2

For SI: 1 foot = 304.8 mm, 1 watt per square foot = W/0.0929 m2.

  1. In cases where both a general building area type and a more specific building area type are listed, the more specific building area type shall apply.
  2. First LPD value applies if no less than 30 percent of conditioned floor area is in daylight zones. Automatic daylighting controls shall be installed in daylight zones and shall meet the requirements of Section C405.2.2.3. In all other cases, second LPD value applies.
  3. No less than 70 percent of the floor area shall be in the daylight zone. Automatic daylighting controls shall be installed in daylight zones and shall meet the requirements of Section C405.2.2.3.
The total interior lighting power (watts) of the building shall be determined by using the reduced whole building interior lighting power in Table C406.3 times the floor area for the building types.

Total minimum ratings of on-site renewable energy systems shall comply with one of the following:

  1. Provide not less than 1.75 Btu (1850 W), or not less than 0.50 watts per square foot (5.4 W/m2) of conditioned floor area.
  2. Provide not less than 3 percent of the energy used within the building for building mechanical and service water heating equipment and lighting regulated in this chapter.
This section establishes criteria for compliance using total building performance. The following systems and loads shall be included in determining the total building performance: heating systems, cooling systems, service water heating, fan systems, lighting power, receptacle loads and process loads.
Compliance with this section requires that the criteria of Sections C402.4, C403.2, C404 and C405 be met.

Compliance based on total building performance requires that a proposed building (proposed design) be shown to have an annual energy cost that is less than or equal to the annual energy cost of the standard reference design. Energy prices shall be taken from a source approved by the code official, such as the Department of Energy, Energy Information Administration’s State Energy Price and Expenditure Report. Code officials shall be permitted to require time-of-use pricing in energy cost calculations. Nondepletable energy collected off site shall be treated and priced the same as purchased energy. Energy from nondepletable energy sources collected on site shall be omitted from the annual energy cost of the proposed design.

Exception: Jurisdictions that require site energy (1 kWh = 3413 Btu) rather than energy cost as the metric of comparison.

Documentation verifying that the methods and accuracy of compliance software tools conform to the provisions of this section shall be provided to the code official.

Compliance software tools shall generate a report that documents that the proposed design has annual energy costs less than or equal to the annual energy costs of the standard reference design. The compliance documentation shall include the following information:

  1. Address of the building;
  2. An inspection checklist documenting the building component characteristics of the proposed design as listed in Table C407.5.1(1). The inspection checklist shall show the estimated annual energy cost for both the standard reference design and the proposed design;
  3. Name of individual completing the compliance report; and
  4. Name and version of the compliance software tool.

The code official shall be permitted to require the following documents:

  1. Documentation of the building component characteristics of the standard reference design;
  2. Thermal zoning diagrams consisting of floor plans showing the thermal zoning scheme for standard reference design and proposed design;
  3. Input and output report(s) from the energy analysis simulation program containing the complete input and output files, as applicable. The output file shall include energy use totals and energy use by energy source and end-use served, total hours that space conditioning loads are not met and any errors or warning messages generated by the simulation tool as applicable;
  4. An explanation of any error or warning messages appearing in the simulation tool output; and
  5. A certification signed by the builder providing the building component characteristics of the proposed design as given in Table C407.5.1(1).
Except as specified by this section, the standard reference design and proposed design shall be configured and analyzed using identical methods and techniques.

The standard reference design and proposed design shall be configured and analyzed as specified by Table C407.5.1(1). Table C407.5.1(1) shall include by reference all notes contained in Table C402.2.

TABLE C407.5.1(1)

SPECIFICATIONS FOR THE STANDARD REFERENCE AND PROPOSED DESIGNS

BUILDING COMPONENT
CHARACTERISTICS
STANDARD REFERENCE DESIGNPROPOSED DESIGN
Space use classificationSame as proposedThe space use classification shall be chosen in
accordance with Table C405.5.2 for all areas of the
building covered by this permit. Where the space use
classification for a building is not known, the building
shall be categorized as an office building.
RoofsType: Insulation entirely above deckAs proposed
Gross area: same as proposedAs proposed
U-factor: from Table C402.1.2As proposed
Solar absorptance: 0.75As proposed
Emittance: 0.90As proposed
Walls, above-gradeType: Mass wall if proposed wall is mass; otherwise steel-framed wallAs proposed
Gross area: same as proposedAs proposed
U-factor: from Table C402.1.2As proposed
Solar absorptance: 0.75As proposed
Emittance: 0.90As proposed
Walls, below-gradeType: Mass wallAs proposed
Gross area: same as proposedAs proposed
U-Factor: from Table C402.1.2 with insulation layer on interior side of wallsAs proposed
Floors, above-gradeType: joist/framed floorAs proposed
Gross area: same as proposedAs proposed
U-factor: from Table C402.1.2As proposed
Floors, slab-on-gradeType: UnheatedAs proposed
F-factor: from Table C402.1.2As proposed
DoorsType: SwingingAs proposed
Area: Same as proposedAs proposed
U-factor: from Table C402.2As proposed
GlazingArea
1. The proposed glazing area; where the proposed glazing area is
less than 40 percent of above-grade wall area.
2. 40 percent of above-grade wall area; where the proposed
glazing area is 40 percent or more of the above-grade wall area.
As proposed
U-factor: from Table C402.3As proposed
SHGC: from Table C402.3 except that for climates with no
requirement (NR) SHGC = 0.40 shall be used
As proposed
External shading and PF: NoneAs proposed
SkylightsArea
1. The proposed skylight area; where the proposed skylight area is less
than 3 percent of gross area of roof assembly.
2. 3 percent of gross area of roof assembly; where the proposed skylight
area is 3 percent or more of gross area of roof assembly
As proposed
U-factor: from Table C402.3As proposed
SHGC: from Table C402.3 except that for climates with no
requirement (NR) SHGC = 0.40 shall be used.
As proposed
Lighting, interiorThe interior lighting power shall be determined in accordance with
Section C405.5.2. Where the occupancy of the building is not known,
the lighting power density shall be 1.0 Watt per square foot (10.73
W/m2) based on the categorization of buildings with unknown space
classification as offices.
As proposed
Lighting, exteriorThe lighting power shall be determined in accordance with
Table C405.6.2(2). Areas and dimensions of tradable and nontradable
surfaces shall be the same as proposed.
As proposed
Internal gainsSame as proposedReceptacle, motor and process loads shall be
modeled and estimated based on the space use
classification. All end-use load components within
and associated with the building shall be modeled to
include, but not be limited to, the following:
exhaust fans, parking garage ventilation fans,
exterior building lighting, swimming pool heaters
and pumps, elevators, escalators, refrigeration
equipment and cooking equipment.
SchedulesSame as proposedOperating schedules shall include hourly profiles
for daily operation and shall account for variations
between weekdays, weekends, holidays and any
seasonal operation. Schedules shall model the time-
dependent variations in occupancy, illumination,
receptacle loads, thermostat settings, mechanical
ventilation, HVAC equipment availability, service
hot water usage and any process loads. The
schedules shall be typical of the proposed building
type as determined by the designer and approved
by the jurisdiction.
Mechanical ventilationSame as proposedAs proposed, in accordance with Section C403.2.5.
Heating systemsFuel type: same as proposed designAs proposed
Equipment typea: from Tables C407.5.1(2) and C407.5.1(3)As proposed
Efficiency: from Tables C403.2.3(4) and C403.2.3(5)As proposed
Capacityb: sized proportionally to the capacities in the proposed design
based on sizing runs, and shall be established such that no smaller
number of unmet heating load hours and no larger heating capacity
safety factors are provided than in the proposed design.
As proposed
Cooling systemsFuel type: same as proposed designAs proposed
Equipment typec: from Tables C407.5.1(2) and C407.5.1(3)As proposed
Efficiency: from Tables C403.2.3(1), C403.2.3(2) and C403.2.3(3)As proposed
Capacityb: sized proportionally to the capacities in the proposed design
based on sizing runs, and shall be established such that no smaller
number of unmet cooling load hours and no larger cooling capacity
safety factors are provided than in the proposed design.
As proposed
Economizerd: same as proposed, in accordance with Section C403.4.1.As proposed
Service water heatingFuel type: same as proposedAs proposed
Efficiency: from Table C404.2As proposed
Capacity: same as proposed
Where no service water hot water system exists or is specified in the
proposed design, no service hot water heating shall be modeled.
As proposed
  1. Where no heating system exists or has been specified, the heating system shall be modeled as fossil fuel. The system characteristics shall be identical in both the standard reference design and proposed design.
  2. The ratio between the capacities used in the annual simulations and the capacities determined by sizing runs shall be the same for both the standard reference design and proposed design.
  3. Where no cooling system exists or no cooling system has been specified, the cooling system shall be modeled as an air-cooled single-zone system, one unit per thermal zone. The system characteristics shall be identical in both the standard reference design and proposed design.
  4. If an economizer is required in accordance with Table C403.3.1(1), and if no economizer exists or is specified in the proposed design, then a supply air economizer shall be provided in accordance with Section C403.4.1.

TABLE C407.5.1(2)

HVAC SYSTEMS MAP

CONDENSER COOLING
SOURCEa
HEATING SYSTEM
CLASSIFICATIONb
STANDARD REFERENCE DESIGN HVC SYSTEM TYPEc
Single-zone Residential
System
Single-zone Nonresidential
System
All Other
Water/groundElectric resistanceSystem 5System 5System 1
Heat pumpSystem 6System 6System 6
Fossil fuelSystem 7System 7System 2
Air/noneElectric resistanceSystem 8System 9System 3
Heat pumpSystem 8System 9System 3
Fossil fuelSystem 10System 11System 4
  1. Select “water/ground” if the proposed design system condenser is water or evaporatively cooled; select “air/none” if the condenser is air cooled. Closed-circuit dry coolers shall be considered air cooled. Systems utilizing district cooling shall be treated as if the condenser water type were “water.” If no mechanical cooling is specified or the mechanical cooling system in the proposed design does not require heat rejection, the system shall be treated as if the condenser water type were “Air.” For proposed designs with ground-source or groundwater-source heat pumps, the standard reference design HVAC system shall be water-source heat pump (System 6).
  2. Select the path that corresponds to the proposed design heat source: electric resistance, heat pump (including air source and water source), or fuel fired. Systems utilizing district heating (steam or hot water) and systems with no heating capability shall be treated as if the heating system type were “fossil fuel.” For systems with mixed fuel heating sources, the system or systems that use the secondary heating source type (the one with the smallest total installed output capacity for the spaces served by the system) shall be modeled identically in the standard reference design and the primary heating source type shall be used to determine standard reference design HVAC system type.
  3. Select the standard reference design HVAC system category: The system under “single-zone residential system” shall be selected if the HVAC system in the proposed design is a single-zone system and serves a residential space. The system under “single-zone nonresidential system” shall be selected if the HVAC system in the proposed design is a single-zone system and serves other than residential spaces. The system under “all other” shall be selected for all other cases.

TABLE C407.5.1(3)

SPECIFICATIONS FOR THE STANDARD REFERENCE DESIGN HVAC SYSTEM DESCRIPTIONS

SYSTEM NO.SYSTEM TYPEFAN CONTROLCOOLING TYPEHEATING TYPE
1Variable air volume with parallel fan-powered boxesaVAVdChilled watereElectric resistance
2Variable air volume with reheatbVAVdChilled watereHot water fossil fuel boilerf
3Packaged variable air volume with parallel fan-powered boxesaVAVdDirect expansioncElectric resistance
4Packaged variable air volume with reheatbVAVdDirect expansioncHot water fossil fuel boilerf
5Two-pipe fan coilConstant volumeiChilled watereElectric resistance
6Water-source heat pumpConstant volumeiDirect expansioncElectric heat pump and boilerg
7Four-pipe fan coilConstant volumeiChilled watereHot water fossil fuel boilerf
8Packaged terminal heat pumpConstant volumeiDirect expansioncElectric heat pumph
9Packaged rooftop heat pumpConstant volumeiDirect expansioncElectric heat pumph
10Packaged terminal air conditionerConstant volumeiDirect expansionHot water fossil fuel boilerf
11Packaged rooftop air conditionerConstant volumeiDirect expansionFossil fuel furnace

For SI: 1 foot = 304.8 mm, 1 cfm/ft2 = 0.0004719, 1 Btu/h = 0.293/W, °C = [(°F) -32/1.8].

  1. VAV with parallel boxes: Fans in parallel VAV fan-powered boxes shall be sized for 50 percent of the peak design flow rate and shall be modeled with 0.35 W/cfm fan power. Minimum volume setpoints for fan-powered boxes shall be equal to the minimum rate for the space required for ventilation consistent with Section C403.4.5, Exception 5. Supply air temperature setpoint shall be constant at the design condition.
  2. VAV with reheat: Minimum volume setpoints for VAV reheat boxes shall be 0.4 cfm/ft2 of floor area. Supply air temperature shall be reset based on zone demand from the design temperature difference to a 10°F temperature difference under minimum load conditions. Design airflow rates shall be sized for the reset supply air temperature, i.e., a 10°F temperature difference.
  3. Direct expansion: The fuel type for the cooling system shall match that of the cooling system in the proposed design.
  4. VAV: Constant volume can be modeled if the system qualifies for Exception 1, Section C403.4.5. When the proposed design system has a supply, return or relief fan motor 25 horsepower (hp) or larger, the corresponding fan in the VAV system of the standard reference design shall be modeled assuming a variable speed drive. For smaller fans, a forward-curved centrifugal fan with inlet vanes shall be modeled. If the proposed design's system has a direct digital control system at the zone level, static pressure setpoint reset based on zone requirements in accordance with Section C403.4.2 shall be modeled.
  5. Chilled water: For systems using purchased chilled water, the chillers are not explicitly modeled and chilled water costs shall be based as determined in Sections C407.3 and C407.5.2. Otherwise, the standard reference design’s chiller plant shall be modeled with chillers having the number as indicated in Table C407.5.1(4) as a function of standard reference building chiller plant load and type as indicated in Table C407.5.1(5) as a function of individual chiller load. Where chiller fuel source is mixed, the system in the standard reference design shall have chillers with the same fuel types and with capacities having the same proportional capacity as the proposed design’s chillers for each fuel type. Chilled water supply temperature shall be modeled at 44°F design supply temperature and 56°F return temperature. Piping losses shall not be modeled in either building model. Chilled water supply water temperature shall be reset in accordance with Section C403.4.3.4. Pump system power for each pumping system shall be the same as the proposed design; if the proposed design has no chilled water pumps, the standard reference design pump power shall be 22 W/gpm (equal to a pump operating against a 75-foot head, 65-percent combined impeller and motor efficiency). The chilled water system shall be modeled as primary-only variable flow with flow maintained at the design rate through each chiller using a bypass. Chilled water pumps shall be modeled as riding the pump curve or with variable-speed drives when required in Section C403.4.3.4. The heat rejection device shall be an axial fan cooling tower with two-speed fans if required in Section C403.4.4. Condenser water design supply temperature shall be 85°F or 10°F approach to design wet-bulb temperature, whichever is lower, with a design temperature rise of 10°F. The tower shall be controlled to maintain a 70°F leaving water temperature where weather permits, floating up to leaving water temperature at design conditions. Pump system power for each pumping system shall be the same as the proposed design; if the proposed design has no condenser water pumps, the standard reference design pump power shall be 19 W/gpm (equal to a pump operating against a 60-foot head, 60-percent combined impeller and motor efficiency). Each chiller shall be modeled with separate condenser water and chilled water pumps interlocked to operate with the associated chiller.
  6. Fossil fuel boiler: For systems using purchased hot water or steam, the boilers are not explicitly modeled and hot water or steam costs shall be based on actual utility rates. Otherwise, the boiler plant shall use the same fuel as the proposed design and shall be natural draft. The standard reference design boiler plant shall be modeled with a single boiler if the standard reference design plant load is 600,000 Btu/h and less and with two equally sized boilers for plant capacities exceeding 600,000 Btu/h. Boilers shall be staged as required by the load. Hot water supply temperature shall be modeled at 180°F design supply temperature and 130°F return temperature. Piping losses shall not be modeled in either building model. Hot water supply water temperature shall be reset in accordance with Section C403.4.3.4. Pump system power for each pumping system shall be the same as the proposed design; if the proposed design has no hot water pumps, the standard reference design pump power shall be 19 W/gpm (equal to a pump operating against a 60-foot head, 60-percent combined impeller and motor efficiency). The hot water system shall be modeled as primary only with continuous variable flow. Hot water pumps shall be modeled as riding the pump curve or with variable speed drives when required by Section C403.4.3.4.
  7. Electric heat pump and boiler: Water-source heat pumps shall be connected to a common heat pump water loop controlled to maintain temperatures between 60°F and 90°F. Heat rejection from the loop shall be provided by an axial fan closed-circuit evaporative fluid cooler with two-speed fans if required in Section C403.4.2. Heat addition to the loop shall be provided by a boiler that uses the same fuel as the proposed design and shall be natural draft. If no boilers exist in the proposed design, the standard reference building boilers shall be fossil fuel. The standard reference design boiler plant shall be modeled with a single boiler if the standard reference design plant load is 600,000 Btu/h or less and with two equally sized boilers for plant capacities exceeding 600,000 Btu/h. Boilers shall be staged as required by the load. Piping losses shall not be modeled in either building model. Pump system power shall be the same as the proposed design; if the proposed design has no pumps, the standard reference design pump power shall be 22 W/gpm, which is equal to a pump operating against a 75-foot head, with a 65-percent combined impeller and motor efficiency. Loop flow shall be variable with flow shutoff at each heat pump when its compressor cycles off as required by Section C403.4.3.3. Loop pumps shall be modeled as riding the pump curve or with variable speed drives when required by Section C403.4.3.4.
  8. Electric heat pump: Electric air-source heat pumps shall be modeled with electric auxiliary heat. The system shall be controlled with a multistage space thermostat and an outdoor air thermostat wired to energize auxiliary heat only on the last thermostat stage and when outdoor air temperature is less than 40°F.
  9. Constant volume: Fans shall be controlled in the same manner as in the proposed design; i.e., fan operation whenever the space is occupied or fan operation cycled on calls for heating and cooling. If the fan is modeled as cycling and the fan energy is included in the energy efficiency rating of the equipment, fan energy shall not be modeled explicitly.

TABLE C407.5.1(4)

NUMBER OF CHILLERS

TOTAL CHILLER PLANT CAPACITYNUMBER OF CHILLERS
≤ 300 tons1
> 300 tons, < 600 tons2, sized equally
≥ 600 tons2 minimum, with chillers added so that no chiller is larger than 800 tons, all sized equally

For SI: 1 ton = 3517 W.

TABLE C407.5.1(5)

WATER CHILLER TYPES

INDIVIDUAL CHILLER PLANT CAPACITYELECTRIC-CHILLER TYPEFOSSIL FUEL CHILLER TYPE
≤ 100 tonsReciprocatingSingle-effect absorption, direct fired
> 100 tons,
< 300 tons
ScrewDouble-effect absorption, direct fired
≥ 300 tonsCentrifugalDouble-effect absorption, direct fired

For SI: 1 ton = 3517 W.

The standard reference design and proposed design shall be analyzed using identical thermal blocks as specified in Section C407.5.2.1, C407.5.2.2 or C407.5.2.3.

Where HVAC zones are defined on HVAC design drawings, each HVAC zone shall be modeled as a separate thermal block.

Exception: Different HVAC zones shall be allowed to be combined to create a single thermal block or identical thermal blocks to which multipliers are applied provided:

  1. The space use classification is the same throughout the thermal block.
  2. All HVAC zones in the thermal block that are adjacent to glazed exterior walls face the same orientation or their orientations are within 45 degrees (0.79 rad) of each other.
  3. All of the zones are served by the same HVAC system or by the same kind of HVAC system.

Where HVAC zones have not yet been designed, thermal blocks shall be defined based on similar internal load densities, occupancy, lighting, thermal and temperature schedules, and in combination with the following guidelines:

  1. Separate thermal blocks shall be assumed for interior and perimeter spaces. Interior spaces shall be those located more than 15 feet (4572 mm) from an exterior wall. Perimeter spaces shall be those located closer than 15 feet (4572 mm) from an exterior wall.
  2. Separate thermal blocks shall be assumed for spaces adjacent to glazed exterior walls: a separate zone shall be provided for each orientation, except orientations that differ by no more than 45 degrees (0.79 rad) shall be permitted to be considered to be the same orientation. Each zone shall include floor area that is 15 feet (4572 mm) or less from a glazed perimeter wall, except that floor area within 15 feet (4572 mm) of glazed perimeter walls having more than one orientation shall be divided proportionately between zones.
  3. Separate thermal blocks shall be assumed for spaces having floors that are in contact with the ground or exposed to ambient conditions from zones that do not share these features.
  4. Separate thermal blocks shall be assumed for spaces having exterior ceiling or roof assemblies from zones that do not share these features.
Residential spaces shall be modeled using one thermal block per space except that those facing the same orientations are permitted to be combined into one thermal block. Corner units and units with roof or floor loads shall only be combined with units sharing these features.

Calculation procedures used to comply with this section shall be software tools capable of calculating the annual energy consumption of all building elements that differ between the standard reference design and the proposed design and shall include the following capabilities.

  1. Computer generation of the standard reference design using only the input for the proposed design. The calculation procedure shall not allow the user to directly modify the building component characteristics of the standard reference design.
  2. Building operation for a full calendar year (8,760 hours).
  3. Climate data for a full calendar year (8,760 hours) and shall reflect approved coincident hourly data for temperature, solar radiation, humidity and wind speed for the building location.
  4. Ten or more thermal zones.
  5. Thermal mass effects.
  6. Hourly variations in occupancy, illumination, receptacle loads, thermostat settings, mechanical ventilation, HVAC equipment availability, service hot water usage and any process loads.
  7. Part-load performance curves for mechanical equipment.
  8. Capacity and efficiency correction curves for mechanical heating and cooling equipment.
  9. Printed code official inspection checklist listing each of the proposed design component characteristics from Table C407.5.1(1) determined by the analysis to provide compliance, along with their respective performance ratings (e.g., R-value, U-factor, SHGC, HSPF, AFUE, SEER, EF, etc.).
Performance analysis tools meeting the applicable subsections of Section C407 and tested according to ASHRAE Standard 140 shall be permitted to be approved. Tools are permitted to be approved based on meeting a specified threshold for a jurisdiction. The code official shall be permitted to approve tools for a specified application or limited scope.
Where calculations require input values not specified by Sections C402, C403, C404 and C405, those input values shall be taken from an approved source.
This section covers the commissioning of the building mechanical systems in Section C403 and electrical power and lighting systems in Section C405.

Prior to passing the final mechanical inspection, the registered design professional shall provide evidence of mechanical systems commissioning and completion in accordance the provisions of this section.

Construction document notes shall clearly indicate provisions for commissioning and completion requirements in accordance with this section and are permitted to refer to specifications for further requirements. Copies of all documentation shall be given to the owner and made available to the code official upon request in accordance with Sections C408.2.4 and C408.2.5.

Exception: The following systems are exempt from the commissioning requirements:

  1. Mechanical systems in buildings where the total mechanical equipment capacity is less than 480,000 Btu/h (140 690 W) cooling capacity and 600,000 Btu/h (175 860 W) heating capacity.
  2. Systems included in Section C403.3 that serve dwelling units and sleeping units in hotels, motels, boarding houses or similar units.

A commissioning plan shall be developed by a registered design professional or approved agency and shall include the following items:

  1. A narrative description of the activities that will be accomplished during each phase of commissioning, including the personnel intended to accomplish each of the activities.
  2. A listing of the specific equipment, appliances or systems to be tested and a description of the tests to be performed.
  3. Functions to be tested, including, but not limited to calibrations and economizer controls.
  4. Conditions under which the test will be performed. At a minimum, testing shall affirm winter and summer design conditions and full outside air conditions.
  5. Measurable criteria for performance.
HVAC systems shall be balanced in accordance with generally accepted engineering standards. Air and water flow rates shall be measured and adjusted to deliver final flow rates within the tolerances provided in the product specifications. Test and balance activities shall include air system and hydronic system balancing.

Each supply air outlet and zone terminal device shall be equipped with means for air balancing in accordance with the requirements of Chapter 6 of the International Mechanical Code. Discharge dampers are prohibited on constant volume fans and variable volume fans with motors 10 hp (18.6 kW) and larger. Air systems shall be balanced in a manner to first minimize throttling losses then, for fans with system power of greater than 1 hp (0.74 kW), fan speed shall be adjusted to meet design flow conditions.

Exception: Fans with fan motors of 1 hp (0.74 kW) or less.

Individual hydronic heating and cooling coils shall be equipped with means for balancing and measuring flow. Hydronic systems shall be proportionately balanced in a manner to first minimize throttling losses, then the pump impeller shall be trimmed or pump speed shall be adjusted to meet design flow conditions. Each hydronic system shall have either the capability to measure pressure across the pump, or test ports at each side of each pump.

Exceptions:

  1. Pumps with pump motors of 5 hp (3.7 kW) or less.
  2. Where throttling results in no greater than five percent of the nameplate horsepower draw above that required if the impeller were trimmed.
Functional performance testing specified in Sections C408.2.3.1 through C408.2.3.3 shall be conducted.

Equipment functional performance testing shall demonstrate the installation and operation of components, systems, and system-to-system interfacing relationships in accordance with approved plans and specifications such that operation, function, and maintenance serviceability for each of the commissioned systems is confirmed. Testing shall include all modes and sequence of operation, including under full-load, part-load and the following emergency conditions:

  1. All modes as described in the sequence of operation;
  2. Redundant or automatic back-up mode;
  3. Performance of alarms; and
  4. Mode of operation upon a loss of power and restoration of power.

Exception: Unitary or packaged HVAC equipment listed in Tables C403.2.3(1) through C403.2.3(3) that do not require supply air economizers.

HVAC control systems shall be tested to document that control devices, components, equipment, and systems are calibrated, adjusted and operate in accordance with approved plans and specifications. Sequences of operation shall be functionally tested to document they operate in accordance with approved plans and specifications.
Air economizers shall undergo a functional test to determine that they operate in accordance with manufacturer’s specifications.

A preliminary report of commissioning test procedures and results shall be completed and certified by the registered design professional or approved agency and provided to the building owner. The report shall be identified as “Preliminary Commissioning Report” and shall identify:

  1. Itemization of deficiencies found during testing required by this section that have not been corrected at the time of report preparation.
  2. Deferred tests that cannot be performed at the time of report preparation because of climatic conditions.
  3. Climatic conditions required for performance of the deferred tests.
Buildings, or portions thereof, shall not pass the final mechanical inspection until such time as the code official has received a letter of transmittal from the building owner acknowledging that the building owner has received the Preliminary Commissioning Report.
The code official shall be permitted to require that a copy of the Preliminary Commissioning Report be made available for review by the code official.
The construction documents shall specify that the documents described in this section be provided to the building owner within 90 days of the date of receipt of the certificate of occupancy.

Construction documents shall include the location and performance data on each piece of equipment.

An operating and maintenance manual shall be provided and include all of the following:

  1. Submittal data stating equipment size and selected options for each piece of equipment requiring maintenance.
  2. Manufacturer’s operation manuals and maintenance manuals for each piece of equipment requiring maintenance, except equipment not furnished as part of the project. Required routine maintenance actions shall be clearly identified.
  3. Name and address of at least one service agency.
  4. HVAC controls system maintenance and calibration information, including wiring diagrams, schematics, and control sequence descriptions. Desired or field-determined setpoints shall be permanently recorded on control drawings at control devices or, for digital control systems, in system programming instructions.
  5. A narrative of how each system is intended to operate, including recommended setpoints.
A written report describing the activities and measurements completed in accordance with Section C408.2.2.

A report of test procedures and results identified as “Final Commissioning Report” shall be delivered to the building owner and shall include:

  1. Results of functional performance tests.
  2. Disposition of deficiencies found during testing, including details of corrective measures used or proposed.
  3. Functional performance test procedures used during the commissioning process including measurable criteria for test acceptance, provided herein for repeatability.

Exception: Deferred tests which cannot be performed at the time of report preparation due to climatic conditions.

Controls for automatic lighting systems shall comply with Section C408.3.

Testing shall ensure that control hardware and software are calibrated, adjusted, programmed and in proper working condition in accordance with the construction documents and manufacturer’s installation instructions. The construction documents shall state the party who will conduct the required functional testing. Where required by the code official, an approved party independent from the design or construction of the project shall be responsible for the functional testing and shall provide documentation to the code official certifying that the installed lighting controls meet the provisions of Section C405.

Where occupant sensors, time switches, programmable schedule controls, photosensors or daylighting controls are installed, the following procedures shall be performed:

  1. Confirm that the placement, sensitivity and time-out adjustments for occupant sensors yield acceptable performance.
  2. Confirm that the time switches and programmable schedule controls are programmed to turn the lights off.
  3. Confirm that the placement and sensitivity adjustments for photosensor controls reduce electric light based on the amount of usable daylight in the space as specified.
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