ADOPTS WITH AMENDMENTS:

International Energy Conservation Code 2018 (IECC 2018)

IECC — Commercial Provisions

IECC — Residential Provisions

Heads up: There are no amended sections in this chapter.

User note:

About this chapter: Chapter 4 provides requirements for the thermal envelope of a building, including minimum insulation values for walls, ceiling and floors; maximum fenestration U-factors; minimum fenestration solar heat gain coefficients; and methods for determining building assembly and a total building U-factor. A performance alternative and an energy rating alternative are also provided to allow for energy code compliance other than by the prescriptive method.

R401.1 Scope

AMENDMENT
This section has been amended at the state or city level.
This chapter regulates the energy efficiency for the design and construction of buildings regulated by 780 CMR. Municipalities which have adopted the Stretch Energy Code shall use the energy efficiency requirements of 780 CMR 110 Appendix AA.
Exception: Temporary structures, as regulated by Section 3103, do not need to comply with the building envelope requirements of 780 CMR 51.00.

R401.2 Compliance

AMENDMENT
This section has been amended at the state or city level.

Projects shall comply with one of the following:

  1. Prescriptive Path. Sections R401 through R404 and R407.
  2. Performance Path. An energy rating index ("ERI") approach, or approved alternative energy performance rating method in section R406 and the provisions of sections R401 through R404 indicated as "Mandatory." Qualifying approaches under R406 include the following:
    1. Certified RESNET HERS rating with Massachusetts amendments.
    2. Certified Energy Star Homes, Version 3.1.
    3. Certified Passive house performance method.

Residential buildings in the tropical zone at elevations less than 2,400 feet (731.5 m) above sea level shall be deemed to be in compliance with this chapter provided that the following conditions are met:

  1. Not more than one-half of the occupied space is air conditioned.
  2. The occupied space is not heated.
  3. Solar, wind or other renewable energy source supplies not less than 80 percent of the energy for service water heating.
  4. Glazing in conditioned spaces has a solar heat gain coefficient of less than or equal to 0.40, or has an overhang with a projection factor equal to or greater than 0.30.
  5. Permanently installed lighting is in accordance with Section R404.
  6. The exterior roof surface complies with one of the options in Table C402.3 or the roof or ceiling has insulation with an R-value of R-15 or greater. Where attics are present, attics above the insulation are vented and attics below the insulation are unvented.
  7. Roof surfaces have a slope of not less than onefourth unit vertical in 12 units horizontal (21-percent slope). The finished roof does not have water accumulation areas.
  8. Operable fenestration provides a ventilation area of not less than 14 percent of the floor area in each room. Alternatively, equivalent ventilation is provided by a ventilation fan.
  9. Bedrooms with exterior walls facing two different directions have operable fenestration on exterior walls facing two directions.
  10. Interior doors to bedrooms are capable of being secured in the open position.
  11. A ceiling fan or ceiling fan rough-in is provided for bedrooms and the largest space that is not used as a bedroom.

R401.3 Certificate (Mandatory)

AMENDMENT
This section has been amended at the state or city level.
A permanent certificate shall be completed by the builder or other approved party and posted on a wall in the space where the furnace is located, a utility room or an approved location inside the building. Where located on an electrical panel, the certificate shall not cover or obstruct the visibility of the circuit directory label, service disconnect label or other required labels. The certificate shall indicate the predominant R-values of insulation installed in or on ceilings, roofs, walls, foundation components such as slabs, basement walls, crawl space walls and floors and ducts outside conditioned spaces; U-factors of fenestration and the solar heat gain coefficient (SHGC) of fenestration, and the results from any required duct system and building envelope air leakage testing performed on the building. Where there is more than one value for each component, the certificate shall indicate the value covering the largest area. The certificate shall indicate the types and efficiencies of heating, cooling and service water heating equipment. Where a gas-fired unvented room heater, electric furnace or baseboard electric heater is installed in the residence, the certificate shall indicate "gas-fired unvented room heater," "electric furnace" or "baseboard electric heater," as appropriate. An efficiency shall not be indicated for gas-fired unvented room heaters, electric furnaces and electric baseboard heaters. The Certificate shall list the final HERS index score when applicable.

The building thermal envelope shall comply with the requirements of Sections R402.1.1 through R402.1.5.

Exceptions:

  1. The following low-energy buildings, or portions thereof, separated from the remainder of the building by building thermal envelope assemblies complying with this section shall be exempt from the building thermal envelope provisions of Section R402.

    1. 1.1. Those with a peak design rate of energy usage less than 3.4 Btu/h ft2 (10.7 W/m2) or 1.0 watt/ft2 of floor area for space-conditioning purposes.
    2. 1.2. Those that do not contain conditioned space.
  2. Log homes designed in accordance with ICC 400.
Wall assemblies in the building thermal envelope shall comply with the vapor retarder requirements of Section R702.7 of the International Residential Code or Section 1404.3 of the International Building Code, as applicable.

The building thermal envelope shall meet the requirements of Table R402.1.2, based on the climate zone specified in Chapter 3.

TABLE R402.1.2

INSULATION AND FENESTRATION REQUIREMENTS BY COMPONENTa

CLIMATE
ZONE
FENESTRATION
U-FACTORb
SKYLIGHTb
U-FACTOR
GLAZED
FENESTRATION
SHGCb, e
CEILING
R-VALUE
WOOD
FRAME WALL
R-VALUE
MASS
WALL
R-VALUEi
FLOOR
R-VALUE
BASEMENTc
WALL
R-VALUE
SLABd
R-VALUE
& DEPTH
CRAWL
SPACEc
WALL
R-VALUE
1NR0.750.2530133/413000
20.400.650.2538134/613000
30.320.550.253820 or 13+5h8/13195/13f05/13
4 except
Marine
0.320.550.404920 or 13+5h8/131910/1310, 2 ft10/13
5 and
Marine 4
0.300.55NR4920 or 13+5h13/1730g15/1910, 2 ft15/19
60.300.55NR4920+5h or 13+10h15/2030g15/1910, 4 ft15/19
7 and 80.300.55NR4920+5h or 13+10h19/2138g15/1910, 4 ft15/19

NR = Not Required. For SI: 1 foot = 304.8 mm.

  1. R-values are minimums. U-factors and SHGC are maximums. Where insulation is installed in a cavity that is less than the label or design thickness of the insulation, the installed R-value of the insulation shall be not less than the R-value specified in the table.
  2. The fenestration U-factor column excludes skylights. The SHGC column applies to all glazed fenestration.

    Exception: In Climate Zones 1 through 3, skylights shall be permitted to be excluded from glazed fenestration SHGC requirements provided that the SHGC for such skylights does not exceed 0.30.

  3. "10/13" means R-10 continuous insulation on the interior or exterior of the home or R-13 cavity insulation on the interior of the basement wall. "15/19" means R-15 continuous insulation on the interior or exterior of the home or R-19 cavity insulation at the interior of the basement wall. Alternatively, compliance with "15/19" shall be R-13 cavity insulation on the interior of the basement wall plus R-5 continuous insulation on the interior or exterior of the home.
  4. R-5 insulation shall be provided under the full slab area of a heated slab in addition to the required slab edge insulation R-value for slabs. as indicated in the table. The slab edge insulation for heated slabs shall not be required to extend below the slab.
  5. There are no SHGC requirements in the Marine Zone.
  6. Basement wall insulation is not required in warm-humid locations as defined by Figure R301.1 and Table R301.1.
  7. Alternatively, insulation sufficient to fill the framing cavity and providing not less than an R-value of R-19.
  8. The first value is cavity insulation, the second value is continuous insulation. Therefore, as an example, "13+5" means R-13 cavity insulation plus R-5 continuous insulation.
  9. Mass walls shall be in accordance with Section R402.2.5. The second R-value applies where more than half of the insulation is on the interior of the mass wall.
Insulation material used in layers, such as framing cavity insulation or continuous insulation, shall be summed to compute the corresponding component R-value. The manufacturer's settled R-value shall be used for blown-in insulation. Computed R-values shall not include an R-value for other building materials or air films. Where insulated siding is used for the purpose of complying with the continuous insulation requirements of Table R402.1.2, the manufacturer's labeled R-value for the insulated siding shall be reduced by R-0.6.

An assembly with a U-factor equal to or less than that specified in Table R402.1.4 shall be an alternative to the R-value in Table R402.1.2.

TABLE R402.1.4

EQUIVALENT U-FACTORSa

CLIMATE
ZONE
FENESTRATION
U-FACTOR
SKYLIGHT
U-FACTOR
CEILING
U-FACTOR
FRAME
WALL
U-FACTOR
MASS WALL
U-FACTORb
FLOOR
U-FACTOR
BASEMENT
WALL
U-FACTOR
CRAWL
SPACE WALL
U-FACTOR
10.500.750.0350.0840.1970.0640.3600.477
20.400.650.0300.0840.1650.0640.3600.477
30.320.550.0300.0600.0980.0470.091c0.136
4 except Marine0.320.550.0260.0600.0980.0470.0590.065
5 and Marine 40.300.550.0260.0600.0820.0330.0500.055
60.300.550.0260.0450.0600.0330.0500.055
7 and 80.300.550.0260.0450.0570.0280.0500.055
  1. Nonfenestration U-factors shall be obtained from measurement, calculation or an approved source.
  2. Mass walls shall be in accordance with Section R402.2.5. Where more than half the insulation is on the interior, the mass wall U-factors shall not exceed 0.17 in Climate Zone 1, 0.14 in Climate Zone 2, 0.12 in Climate Zone 3, 0.087 in Climate Zone 4 except Marine, 0.065 in Climate Zone 5 and Marine 4, and 0.057 in Climate Zones 6 through 8.
  3. In warm-humid locations as defined by Figure R301.1 and Table R301.1, the basement wall U-factor shall not exceed 0.360.
Where the total building thermal envelope UA, the sum of U-factor times assembly area, is less than or equal to the total UA resulting from multiplying the U-factors in Table R402.1.4 by the same assembly area as in the proposed building, the building shall be considered to be in compliance with Table R402.1.2. The UA calculation shall be performed using a method consistent with the ASHRAE Handbook of Fundamentals and shall include the thermal bridging effects of framing materials. In addition to UA compliance, the SHGC requirements shall be met.

R402.1.5.1 Approved Software for Prescriptive Path Total UA Alternative

AMENDMENT
This section has been amended at the state or city level.
The following software is approved for demonstrating Total UA compliance: REScheck—Web or REScheck for Windows Version 4.6.5 or later, available at http://www.energycodes.gov/rescheck
In addition to the requirements of Section R402.1, insulation shall meet the specific requirements of Sections R402.2.1 through R402.2.13.
Where Section R402.1.2 requires R-38 insulation in the ceiling, installing R-30 over 100 percent of the ceiling area requiring insulation shall satisfy the requirement for R-38 wherever the full height of uncompressed R-30 insulation extends over the wall top plate at the eaves. Where Section R402.1.2 requires R-49 insulation in the ceiling, installing R-38 over 100 percent of the ceiling area requiring insulation shall satisfy the requirement for R-49 insulation wherever the full height of uncompressed R-38 insulation extends over the wall top plate at the eaves. This reduction shall not apply to the U-factor alternative approach in Section R402.1.4 and the Total UA alternative in Section R402.1.5.
Where Section R402.1.2 requires insulation R-values greater than R-30 in the ceiling and the design of the roof/ceiling assembly does not allow sufficient space for the required insulation, the minimum required insulation R-value for such roof/ceiling assemblies shall be R-30. Insulation shall extend over the top of the wall plate to the outer edge of such plate and shall not be compressed. This reduction of insulation from the requirements of Section R402.1.2 shall be limited to 500 square feet (46 m2) or 20 percent of the total insulated ceiling area, whichever is less. This reduction shall not apply to the U-factor alternative approach in Section R402.1.4 and the Total UA alternative in Section R402.1.5.
For air-permeable insulations in vented attics, a baffle shall be installed adjacent to soffit and eave vents. Baffles shall maintain an opening equal or greater than the size of the vent. The baffle shall extend over the top of the attic insulation. The baffle shall be permitted to be any solid material.

Access doors from conditioned spaces to unconditioned spaces such as attics and crawl spaces shall be weatherstripped and insulated to a level equivalent to the insulation on the surrounding surfaces. Access that prevents damaging or compressing the insulation shall be provided to all equipment. Where loose-fill insulation is installed, a wood-framed or equivalent baffle or retainer shall be installed to prevent the loose-fill insulation from spilling into the living space when the attic access is opened. The baffle or retainer shall provide a permanent means of maintaining the installed R-value of the loose-fill insulation.

Exception: Vertical doors providing access from conditioned spaces to unconditioned spaces that comply with the fenestration requirements of Table R402.1.2 based on the applicable climate zone specified in Chapter 3.

Mass walls where used as a component of the building thermal envelope shall be one of the following:

  1. Above-ground walls of concrete block, concrete, insulated concrete form, masonry cavity, brick but not brick veneer, adobe, compressed earth block, rammed earth, solid timber or solid logs.
  2. Any wall having a heat capacity greater than or equal to 6 Btu/ft2 ● °F (123 kJ/m2 ● K).

Steel-frame ceilings, walls, and floors shall comply with the insulation requirements of Table R402.2.6 or the U-factor requirements of Table R402.1.4. The calculation of the U-factor for a steel-frame envelope assembly shall use a series-parallel path calculation method.

TABLE R402.2.6

STEEL-FRAME CEILING, WALL AND FLOOR INSULATION R-VALUES

WOOD FRAME
R-VALUE
REQUIREMENT
COLD-FORMED STEEL-FRAME
EQUIVALENT R-VALUEa
Steel Truss Ceilingsb
R-30R-38 or R-30 + 3 or R-26 + 5
R-38R-49 or R-38 + 3
R-49R-38 + 5
Steel Joist Ceilingsb
R-30R-38 in 2 × 4 or 2 × 6 or 2 × 8 R-49
in any framing
R-38R-49 in 2 × 4 or 2 × 6 or 2 × 8 or 2 × 10
Steel-Framed Wall, 16 inches on center
R-13R-13 + 4.2 or R-21 + 2.8 or
R-0 + 9.3 or R-15 + 3.8 or R-21 + 3.1
R-13 + 3R-0 + 11.2 or R-13 + 6.1 or R-15 + 5.7 or
R-19 + 5.0 or R-21 + 4.7
R-20R-0 + 14.0 or R-13 + 8.9 or R-15 + 8.5 or
R-19 + 7.8 or R-19 + 6.2 or R-21 + 7.5
R-20 + 5R-13 + 12.7 or R-15 + 12.3 or R-19 + 11.6 or
R-21 + 11.3 or R-25 + 10.9
R-21R-0 + 14.6 or R-13 + 9.5 or R-15 + 9.1 or
R-19 + 8.4 or R-21 + 8.1 or R-25 + 7.7
Steel Framed Wall, 24 inches on center
R-13R-0 + 9.3 or R-13 + 3.0 or R-15 + 2.4
R-13 + 3R-0 + 11.2 or R-13 + 4.9 or R-15 + 4.3 or
R-19 + 3.5 or R-21 + 3.1
R-20R-0 + 14.0 or R-13 + 7.7 or R-15 + 7.1 or
R-19 + 6.3 or R-21 + 5.9
R-20 + 5R-13 + 11.5 or R-15 + 10.9 or R-19 + 10.1 or
R-21 + 9.7 or R-25 + 9.1
R-21R-0 + 14.6 or R-13 + 8.3 or R-15 + 7.7 or
R-19 + 6.9 or R-21 + 6.5 or R-25 + 5.9
Steel Joist Floor
R-13R-19 in 2 × 6, or R-19 + 6 in 2 × 8 or 2 × 10
R-19R-19 + 6 in 2 × 6, or R-19 + 12 in 2 × 8 or 2 × 10
  1. The first value is cavity insulation R-value, the second value is continuous insulation R-value. Therefore, for example, "R-30+3" means R-30 cavity insulation plus R-3 continuous insulation.
  2. Insulation exceeding the height of the framing shall cover the framing.
Where Section R402.1.2 requires continuous insulation on exterior walls and structural sheathing covers 40 percent or less of the gross area of all exterior walls, the required continuous insulation R-value shall be permitted to be reduced by an amount necessary, but not more than R-3 to result in a consistent total sheathing thickness on areas of the walls covered by structural sheathing. This reduction shall not apply to the U-factor alternative in Section R402.1.4 and the Total UA alternative in Section R402.1.5.

Floor framing-cavity insulation shall be installed to maintain permanent contact with the underside of the subfloor decking.

Exception: As an alternative, the floor framing-cavity insulation shall be in contact with the topside of sheathing or continuous insulation installed on the bottom side of floor framing where combined with insulation that meets or exceeds the minimum wood frame wall R-value in Table R402.1.2 and that extends from the bottom to the top of all perimeter floor framing members.

Walls associated with conditioned basements shall be insulated from the top of the basement wall down to 10 feet (3048 mm) below grade or to the basement floor, whichever is less. Walls associated with unconditioned basements shall comply with this requirement except where the floor overhead is insulated in accordance with Sections R402.1.2 and R402.2.8.
Slab-on-grade floors with a floor surface less than 12 inches (305 mm) below grade shall be insulated in accordance with Table R402.1.2. The insulation shall extend downward from the top of the slab on the outside or inside of the foundation wall. Insulation located below grade shall be extended the distance provided in Table R402.1.2 by any combination of vertical insulation, insulation extending under the slab or insulation extending out from the building. Insulation extending away from the building shall be protected by pavement or by not less than 10 inches (254 mm) of soil. The top edge of the insulation installed between the exterior wall and the edge of the interior slab shall be permitted to be cut at a 45-degree (0.79 rad) angle away from the exterior wall. Slab-edge insulation is not required in jurisdictions designated by the code official as having a very heavy termite infestation.
As an alternative to insulating floors over crawl spaces, crawl space walls shall be insulated provided that the crawl space is not vented to the outdoors. Crawl space wall insulation shall be permanently fastened to the wall and shall extend downward from the floor to the finished grade elevation and then vertically or horizontally for not less than an additional 24 inches (610 mm). Exposed earth in unvented crawl space foundations shall be covered with a continuous Class I vapor retarder in accordance with the International Building Code or International Residential Code, as applicable. Joints of the vapor retarder shall overlap by 6 inches (153 mm) and be sealed or taped. The edges of the vapor retarder shall extend not less than 6 inches (153 mm) up stem walls and shall be attached to the stem walls.
Insulation shall not be required on the horizontal portion of a foundation that supports a masonry veneer.

Sunrooms enclosing conditioned space shall meet the insulation requirements of this code.

Exception: For sunrooms with thermal isolation, and enclosing conditioned space, the following exceptions to the insulation requirements of this code shall apply:

  1. The minimum ceiling insulation R-values shall be R-19 in Climate Zones 1 through 4 and R-24 in Climate Zones 5 through 8.
  2. The minimum wall insulation R-value shall be R-13 in all climate zones. Walls separating a sunroom with a thermal isolation from conditioned space shall comply with the building thermal envelope requirements of this code.
In addition to the requirements of Section R402, fenestration shall comply with Sections R402.3.1 through R402.3.5.
An area-weighted average of fenestration products shall be permitted to satisfy the U-factor requirements.

An area-weighted average of fenestration products more than 50-percent glazed shall be permitted to satisfy the SHGC requirements.

Dynamic glazing shall be permitted to satisfy the SHGC requirements of Table R402.1.2 provided that the ratio of the higher to lower labeled SHGC is greater than or equal to 2.4, and the dynamic glazing is automatically controlled to modulate the amount of solar gain into the space in multiple steps. Dynamic glazing shall be considered separately from other fenestration, and area-weighted averaging with other fenestration that is not dynamic glazing shall be prohibited.

Exception: Dynamic glazing shall not be required to comply with this section where both the lower and higher labeled SHGC comply with the requirements of Table R402.1.2.

Not greater than 15 square feet (1.4 m2) of glazed fenestration per dwelling unit shall be exempt from the U-factor and SHGC requirements in Section R402.1.2. This exemption shall not apply to the U-factor alternative in Section R402.1.4 and the Total UA alternative in Section R402.1.5.
One side-hinged opaque door assembly not greater than 24 square feet (2.22 m2) in area shall be exempt from the U-factor requirement in Section R402.1.2. This exemption shall not apply to the U-factor alternative in Section R402.1.4 and the Total UA alternative in Section R402.1.5.

Sunrooms enclosing conditioned space shall comply with the fenestration requirements of this code.

Exception: In Climate Zones 2 through 8, for sunrooms with thermal isolation and enclosing conditioned space, the fenestration U-factor shall not exceed 0.45 and the skylight U-factor shall not exceed 0.70.

New fenestration separating the sunroom with thermal isolation from conditioned space shall comply with the building thermal envelope requirements of this code.

The building thermal envelope shall be constructed to limit air leakage in accordance with the requirements of Sections R402.4.1 through R402.4.5.
The building thermal envelope shall comply with Sections R402.4.1.1 and R402.4.1.2. The sealing methods between dissimilar materials shall allow for differential expansion and contraction.

R402.4.1.1 Installation

AMENDMENT
This section has been amended at the state or city level.

The components of the building thermal envelope as indicated in Table R402.4.1.1 shall be installed in accordance with the manufacturer's instructions and the criteria indicated in Table R402.4.1.1, as applicable to the method of construction. Where required by the code official, an approved third party shall inspect all components and verify compliance.

TABLE R402.4.1.1

AIR BARRIER AND INSULATION INSTALLATIONa

COMPONENTAIR BARRIER CRITERIAINSULATION INSTALLATION CRITERIA
General requirementsA continuous air barrier shall be installed in the
building envelope.
The exterior thermal envelope contains a continuousBreaks or joints in the air barrier shall be sealed.
All insulation shall be installed at Grade I quality in accordance with ICC/RESNET 301. Air-permeable insulation shall not be used as a
sealing material.
Ceiling/atticThe air barrier in any dropped ceiling or soffit shall be
aligned with the insulation and any gaps in the air
barrier shall be sealed.
Access openings, drop down stairs or knee wall doors
to unconditioned attic spaces shall be sealed.
The insulation in any dropped ceiling/soffit shall
be aligned with the air barrier.
WallsThe junction of the foundation and sill plate shall be
sealed.
The junction of the top plate and the top of exterior
walls shall be sealed.
Knee walls shall be sealed.
Cavities within corners and headers of frame
walls shall be insulated by completely filling the
cavity with a material having a thermal resistance,
R-value, of not less than R-3 per inch.
Exterior thermal envelope insulation for framed
walls shall be installed in substantial contact and
continuous alignment with the air barrier.
Windows, skylights and doorsThe space between framing and skylights, and the jambs
of windows and doors, shall be sealed.
Rim joistsRim joists shall include the air barrier.Rim joists shall be insulated.
Floors, including cantilevered
floors and floors above
garages
The air barrier shall be installed at any exposed edge of
insulation.
Floor framing cavity insulation shall be installed to
maintain permanent contact with the underside of
subfloor decking. Alternatively, floor framing
cavity insulation shall be in contact with the top side
of sheathing, or continuous insulation installed on
the underside of floor framing; and shall extend
from the bottom to the top of all perimeter floor
framing members.
Crawl space wallsExposed earth in unvented crawl spaces shall be
covered with a Class I vapor retarder with
overlapping joints taped.
Crawl space insulation, where provided instead of
floor insulation, shall be permanently attached to
the walls.
Shafts, penetrationsDuct shafts, utility penetrations, and flue shafts
opening to exterior or unconditioned space shall be
sealed.
Narrow cavitiesBatts to be installed in narrow cavities shall be cut to
fit or narrow cavities shall be filled with insulation
that on installation readily conforms to the available
cavity space
.
Garage separationAir sealing shall be provided between the garage and
Recessed lightingRecessed light fixtures installed in the building thermal
envelope shall be sealed to the finished surface.
Recessed light fixtures installed in the building
thermal envelope shall be air tight and IC rated.
Plumbing and wiringIn exterior walls, batt insulation shall be cut neatly to
fit around wiring and plumbing, or insulation, that
on installation readily conforms to available space,
shall extend behind piping and wiring.
Shower/tub on exterior wallThe air barrier installed at exterior walls adjacent to
showers and tubs shall separate the wall from the
shower or tub.
Exterior walls adjacent to showers and tubs shall
be insulated.
Electrical/phone box on exterior wallsThe air barrier shall be installed behind electrical and
communication boxes. Alternatively, air-sealed boxes
shall be installed.
HVAC register bootsHVAC supply and return register boots that penetrate
building thermal envelope shall be sealed to the subfloor,
wall covering or ceiling penetrated by the boot.
Concealed sprinklersWhere required to be sealed, concealed fire sprinklers
shall only be sealed in a manner that is recommended
by the manufacturer. Caulking or other adhesive
sealants shall not be used to fill voids between fire
sprinkler cover plates and walls or ceilings.
  1. Inspection of log walls shall be in accordance with the provisions of ICC 400.

The building or dwelling unit shall be tested and verified as having an air leakage rate not exceeding five air changes per hour in Climate Zones 1 and 2, and three air changes per hour in Climate Zones 3 through 8. Testing shall be conducted in accordance with RESNET/ICC 380, ASTM E 779 or ASTM E 1827 and reported at a pressure of 0.2 inch w.g. (50 Pascals). Where required by the code official, testing shall be conducted by an approved third party. A written report of the results of the test shall be signed by the party conducting the test and provided to the code official. Testing shall be performed at any time after creation of all penetrations of the building thermal envelope.

During testing:

  1. Exterior windows and doors, fireplace and stove doors shall be closed, but not sealed, beyond the intended weatherstripping or other infiltration control measures.
  2. Dampers including exhaust, intake, makeup air, backdraft and flue dampers shall be closed, but not sealed beyond intended infiltration control measures.
  3. Interior doors, where installed at the time of the test, shall be open.
  4. Exterior or interior terminations for continuous ventilation systems shall be sealed.
  5. Heating and cooling systems, where installed at the time of the test, shall be turned off.
  6. Supply and return registers, where installed at the time of the test, shall be fully open.
New wood-burning fireplaces shall have tight-fitting flue dampers or doors, and outdoor combustion air. Where using tight-fitting doors on factory-built fireplaces listed and labeled in accordance with UL 127, the doors shall be tested and listed for the fireplace.

Windows, skylights and sliding glass doors shall have an air infiltration rate of not greater than 0.3 cfm per square foot (1.5 L/s/m2), and for swinging doors, not greater than 0.5 cfm per square foot (2.6 L/s/m2), when tested in accordance with NFRC 400 or AAMA/WDMA/CSA 101/I.S.2/A440 by an accredited, independent laboratory and listed and labeled by the manufacturer.

Exception: Site-built windows, skylights and doors.

In Climate Zones 3 through 8, where open combustion air ducts provide combustion air to open combustion fuel burning appliances, the appliances and combustion air opening shall be located outside the building thermal envelope or enclosed in a room that is isolated from inside the thermal envelope. Such rooms shall be sealed and insulated in accordance with the envelope requirements of Table R402.1.2, where the walls, floors and ceilings shall meet not less than the basement wall R-value requirement. The door into the room shall be fully gasketed and any water lines and ducts in the room insulated in accordance with Section R403. The combustion air duct shall be insulated where it passes through conditioned space to an R-value of not less than R-8.

Exceptions:

  1. Direct vent appliances with both intake and exhaust pipes installed continuous to the outside.
  2. Fireplaces and stoves complying with Section R402.4.2 and Section R1006 of the International Residential Code.
Recessed luminaires installed in the building thermal envelope shall be sealed to limit air leakage between conditioned and unconditioned spaces. Recessed luminaires shall be IC-rated and labeled as having an air leakage rate of not greater than 2.0 cfm (0.944 L/s) when tested in accordance with ASTM E 283 at a pressure differential of 1.57 psf (75 Pa). Recessed luminaires shall be sealed with a gasket or caulked between the housing and the interior wall or ceiling covering.
The area-weighted average maximum fenestration U-factor permitted using tradeoffs from Section R402.1.5 or R405 shall be 0.48 in Climate Zones 4 and 5 and 0.40 in Climate Zones 6 through 8 for vertical fenestration, and 0.75 in Climate Zones 4 through 8 for skylights. The area-weighted average maximum fenestration SHGC permitted using tradeoffs from Section R405 in Climate Zones 1 through 3 shall be 0.50.
Not less than one thermostat shall be provided for each separate heating and cooling system.
The thermostat controlling the primary heating or cooling system of the dwelling unit shall be capable of controlling the heating and cooling system on a daily schedule to maintain different temperature set points at different times of the day. This thermostat shall include the capability to set back or temporarily operate the system to maintain zone temperatures of not less than 55°F (13°C) to not greater than 85°F (29°C). The thermostat shall be programmed initially by the manufacturer with a heating temperature setpoint of not greater than 70°F (21°C) and a cooling temperature setpoint of not less than 78°F (26°C).
Heat pumps having supplementary electric-resistance heat shall have controls that, except during defrost, prevent supplemental heat operation when the heat pump compressor can meet the heating load.
Hot water boilers that supply heat to the building through one- or two-pipe heating systems shall have an outdoor setback control that decreases the boiler water temperature based on the outdoor temperature.
Ducts and air handlers shall be installed in accordance with Sections R403.3.1 through R403.3.7.

Supply and return ducts in attics shall be insulated to an R-value of not less than R-8 for ducts 3 inches (76 mm) in diameter and larger and not less than R-6 for ducts smaller than 3 inches (76 mm) in diameter. Supply and return ducts in other portions of the building shall be insulated to not less than R-6 for ducts 3 inches (76 mm) in diameter and not less than R-4.2 for ducts smaller than 3 inches (76 mm) in diameter.

Exception: Ducts or portions thereof located completely inside the building thermal envelope.

Ducts, air handlers and filter boxes shall be sealed. Joints and seams shall comply with either the International Mechanical Code or International Residential Code, as applicable.
Air handlers shall have a manufacturer's designation for an air leakage of not greater than 2 percent of the design airflow rate when tested in accordance with ASHRAE 193.

R403.3.3 Duct Testing (Mandatory)

AMENDMENT
This section has been amended at the state or city level.

Ducts shall be pressure tested to determine air leakage by one of the following methods:

  1. Rough-in test: Total leakage shall be measured with a pressure differential of 0.1 inch w.g. (25 Pa) across the system, including the manufacturer's air handler enclosure if installed at the time of the test. Registers shall be taped or otherwise sealed during the test.
  2. Postconstruction test: Total leakage shall be measured with a pressure differential of 0.1 inch w.g. (25 Pa) across the entire system, including the manufacturer's air handler enclosure. Registers shall be taped or otherwise sealed during the test.

Exceptions:

  1. A duct air-leakage test shall not be required where the ducts and air handlers are located entirely within the building thermal envelope.
  2. A duct air-leakage test shall not be required for ducts serving heat or energy recovery ventilators that are not integrated with ducts serving heating or cooling systems.

Post-construction or rough-in testing and verification shall be done by a HERS Rater, HERS Rating Field Inspector, or an applicable BPI Certified Professional. A written report of the results of the test shall be signed by the party conducting the test and provided to the code official.

The total leakage of the ducts, where measured in accordance with Section R403.3.3, shall be as follows:

  1. Rough-in test: The total leakage shall be less than or equal to 4 cubic feet per minute (113.3 L/min) per 100 square feet (9.29 m2) of conditioned floor area where the air handler is installed at the time of the test. Where the air handler is not installed at the time of the test, the total leakage shall be less than or equal to 3 cubic feet per minute (85 L/min) per 100 square feet (9.29 m2) of conditioned floor area.
  2. Postconstruction test: Total leakage shall be less than or equal to 4 cubic feet per minute (113.3 L/min) per 100 square feet (9.29 m2) of conditioned floor area.
Building framing cavities shall not be used as ducts or plenums.

Where supply and return air ducts are partially or completely buried in ceiling insulation, such ducts shall comply with all of the following:

  1. The supply and return ducts shall have an insulation R-value not less than R-8.
  2. At all points along each duct, the sum of the ceiling insulation R-value against and above the top of the duct, and against and below the bottom of the duct, shall be not less than R-19, excluding the R-value of the duct insulation.
  3. In Climate Zones 1A, 2A and 3A, the supply ducts shall be completely buried within ceiling insulation, insulated to an R-value of not less than R-13 and in compliance with the vapor retarder requirements of Section 604.11 of the International Mechanical Code or Section M1601.4.6 of the International Residential Code, as applicable.

    Exception: Sections of the supply duct that are less than 3 feet (914 mm) from the supply outlet shall not be required to comply with these requirements.

Where using a simulated energy performance analysis, sections of ducts that are: installed in accordance with Section R403.3.6; located directly on, or within 5.5 inches (140 mm) of the ceiling; surrounded with blown-in attic insulation having an R-value of R-30 or greater and located such that the top of the duct is not less than 3.5 inches (89 mm) below the top of the insulation, shall be considered as having an effective duct insulation R-value of R-25.

For ducts to be considered as inside a conditioned space, such ducts shall comply with either of the following:

  1. The duct system shall be located completely within the continuous air barrier and within the building thermal envelope.
  2. The ducts shall be buried within ceiling insulation in accordance with Section R403.3.6 and all of the following conditions shall exist:

    1. 2.1. The air handler is located completely within the continuous air barrier and within the building thermal envelope.
    2. 2.2. The duct leakage, as measured either by a rough-in test of the ducts or a post-construction total system leakage test to outside the building thermal envelope in accordance with Section R403.3.4, is less than or equal to 1.5 cubic feet per minute (42.5 L/min) per 100 square feet (9.29 m2) of conditioned floor area served by the duct system.
    3. 2.3. The ceiling insulation R-value installed against and above the insulated duct is greater than or equal to the proposed ceiling insulation R-value, less the R-value of the insulation on the duct.
Mechanical system piping capable of carrying fluids greater than 105°F (41°C) or less than 55°F (13°C) shall be insulated to an R-value of not less than R-3.
Piping insulation exposed to weather shall be protected from damage, including that caused by sunlight, moisture, equipment maintenance and wind. The protection shall provide shielding from solar radiation that can cause degradation of the material. Adhesive tape shall be prohibited.
Energy conservation measures for service hot water systems shall be in accordance with Sections R403.5.1 through R403.5.4.
Heated water circulation systems shall be in accordance with Section R403.5.1.1. Heat trace temperature maintenance systems shall be in accordance with Section R403.5.1.2. Automatic controls, temperature sensors and pumps shall be accessible. Manual controls shall be readily accessible.
Heated water circulation systems shall be provided with a circulation pump. The system return pipe shall be a dedicated return pipe or a cold water supply pipe. Gravity and thermosyphon circulation systems shall be prohibited. Controls for circulating hot water system pumps shall start the pump based on the identification of a demand for hot water within the occupancy. The controls shall automatically turn off the pump when the water in the circulation loop is at the desired temperature and when there is no demand for hot water.
Electric heat trace systems shall comply with IEEE 515.1 or UL 515. Controls for such systems shall automatically adjust the energy input to the heat tracing to maintain the desired water temperature in the piping in accordance with the times when heated water is used in the occupancy.

Demand recirculation water systems shall have controls that comply with both of the following:

  1. The controls shall start the pump upon receiving a signal from the action of a user of a fixture or appliance, sensing the presence of a user of a fixture or sensing the flow of hot or tempered water to a fixture fitting or appliance.
  2. The controls shall limit the temperature of the water entering the cold water piping to not greater than 104°F (40°C).

Insulation for hot water piping with a thermal resistance, R-value, of not less than R-3 shall be applied to the following:

  1. Piping 3/4 inch (19.1 mm) and larger in nominal diameter.
  2. Piping serving more than one dwelling unit.
  3. Piping located outside the conditioned space.
  4. Piping from the water heater to a distribution manifold.
  5. Piping located under a floor slab.
  6. Buried piping.
  7. Supply and return piping in recirculation systems other than demand recirculation systems.
Drain water heat recovery units shall comply with CSA B55.2. Drain water heat recovery units shall be tested in accordance with CSA B55.1. Potable water-side pressure loss of drain water heat recovery units shall be less than 3 psi (20.7 kPa) for individual units connected to one or two showers. Potable water-side pressure loss of drain water heat recovery units shall be less than 2 psi (13.8 kPa) for individual units connected to three or more showers.

R403.6 Mechanical Ventilation (Mandatory)

AMENDMENT
This section has been amended at the state or city level.

R403.6 Mechanical Ventilation (Mandatory)

AMENDMENT
This section has been amended at the state or city level.
Outdoor air intakes and exhausts shall have automatic or gravity dampers that close when the ventilation system is not operating. Each dwelling unit of a residential building shall be provided with continuously operating exhaust, supply or balanced mechanical ventilation that has been site verified to meet a minimum airflow per:
  1. R406.3 Equation 4-1:

    Ventilation rate, CFM = (0.01 x total square foot area of house) + [7.5 x (number of bedrooms + 1);
  2. Energy Star Homes Version, 3.1.;
  3. ASHRAE 62.2—2013; or
  4. the following formula for one- and two-family dwellings and townhouses of three or less stories above grade plane:

    Q = .03 x CFA + 7.5 x (Nbr + 1) - 0.052 x Q50 x S x WSF

    Where: CFA is the conditioned floor area in ft2

    Nbr is the number of bedrooms

    Q50 is the verified blower door air leakage rate in cfm measured at 50 Pascals

    S is the building height factor determined by this table:

    Stories above grade plane 1 2 3
    S 1.00 1.32 1.55


    WSF is the shielded weather factor as determined by this table:

    County WSF
    Barnstable 0.6
    Berkshire 0.52
    Bristol 0.54
    Dukes 0.59
    Essex 0.58
    Franklin 0.52
    Hampden 0.49
    Hampshire 0.59
    Middlesex 0.55
    Nantucket 0.61
    Norfolk 0.52
    Plymouth 0.53
    Suffolk 0.66
    Worcester 0.59

Fans used to provide whole-house mechanical ventilation shall meet the efficacy requirements of Table R403.6.1.

Exception: Where an air handler that is integral to tested and listed HVAC equipment is used to provide whole-house mechanical ventilation, the air handler shall be powered by an electronically commutated motor.

TABLE R403.6.1

WHOLE-HOUSE MECHANICAL VENTILATION SYSTEM FAN EFFICACYa

FAN LOCATIONAIR FLOW RATE MINIMUM
(CFM)
MINIMUM EFFICACY
(CFM/WATT)
AIR FLOW RATE MAXIMUM
(CFM)
HRV or ERVAny1.2 cfm/wattAny
Range hoodsAny2.8 cfm/wattAny
In-line fanAny2.8 cfm/wattAny
Bathroom, utility room101.4 cfm/watt< 90
Bathroom, utility room902.8 cfm/wattAny

For SI: 1 cfm = 28.3 L/min.

  1. When tested in accordance with HVI Standard 916.

R403.6.2 Verification

AMENDMENT
This section has been amended at the state or city level.
Installed performance of the mechanical ventilation system shall be tested and verified by a HERS Rater, HERS Rating Field Inspector, or an applicable BPI Certified Professional, and measured using a flow hood, flow grid, or other airflow measuring device in accordance with either RESNET Standard Chapter 8 or ACCA Standard 5.

R403.6.3 Air-Moving Equipment, Selection and Installation

AMENDMENT
This section has been amended at the state or city level.
As referenced in ASHRAE Standard 62.2-2013, section 7.1, ventilation devices and equipment shall be tested and certified by Air Movement and Control Association ("AMCA") or Home Ventilating Institute ("HVI") and the certification label shall be found on the product. Installation of systems or equipment shall be carried out in accordance with manufacturers' design requirements and installation instructions. Where multiple duct sizes and/or exterior hoods are standard options, the minimum size shall not be used.

R403.6.4 Sound Rating

AMENDMENT
This section has been amended at the state or city level.
Sound ratings for fans used for whole building ventilation shall be rated at a maximum of one sone.
Exception: HVAC air handlers and remote-mounted fans need not meet sound requirements. There shall be at least four feet of ductwork between the remote-mounted fan and intake grille.

R403.6.5 Documentation

AMENDMENT
This section has been amended at the state or city level.
The owner and the occupant of the dwelling unit shall be provided with information on the ventilation design and systems installed, as well as instructions on the proper operation and maintenance of the ventilation systems. Ventilation controls shall be labeled with regard to their function, unless the function is obvious.

R403.6.6 Air Inlets and Exhausts

AMENDMENT
This section has been amended at the state or city level.
All ventilation air inlets shall be located a minimum of ten feet from vent openings for plumbing drainage systems, appliance vent outlets, exhaust hood outlets, vehicle exhaust, or other known contamination sources; and shall not be obstructed by snow, plantings, or any other material. Outdoor forced air inlets shall be covered with rodent screens having mesh openings not greater than 1/2 inch. A whole house mechanical ventilation system shall not extract air from an unconditioned basement unless approved by a registered design professional. Where wall inlet or exhaust vents are less than seven feet above finished grade in the area of the venting including, but not limited to, decks and porches, a metal or plastic identification plate shall be permanently mounted to the exterior of the building at a minimum height of eight feet above grade directly in line with the vent terminal. The sign shall read, in print no less than 1/2 inch in size. "MECH. VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS".
Exceptions:
  1. Ventilation air inlets in the wall shall be separated from dryer exhausts and contamination sources exiting through the roof by a minimum of three feet.
  2. No minimum separation distance shall be required between local exhaust outlets in kitchens/bathrooms and windows.
  3. Vent terminations that meet the requirements of the National Fuel Gas Code (NFPA 54/ANSI Z223.1) or equivalent.
Heating and cooling equipment shall be sized in accordance with ACCA Manual S based on building loads calculated in accordance with ACCA Manual J or other approved heating and cooling calculation methodologies. New or replacement heating and cooling equipment shall have an efficiency rating equal to or greater than the minimum required by federal law for the geographic location where the equipment is installed.
Systems serving multiple dwelling units shall comply with Sections C403 and C404 of the International Energy Conservation Code—Commercial Provisions instead of Section R403.
Snow- and ice-melting systems, supplied through energy service to the building, shall include automatic controls capable of shutting off the system when the pavement temperature is greater than 50°F (10°C) and precipitation is not falling, and an automatic or manual control that will allow shutoff when the outdoor temperature is greater than 40°F (4.8°C).
The energy consumption of pools and permanent spas shall be in accordance with Sections R403.10.1 through R403.10.3.
The electric power to heaters shall be controlled by a readily accessible on-off switch that is an integral part of the heater mounted on the exterior of the heater, or external to and within 3 feet (914 mm) of the heater. Operation of such switch shall not change the setting of the heater thermostat. Such switches shall be in addition to a circuit breaker for the power to the heater. Gas-fired heaters shall not be equipped with continuously burning ignition pilots.

Time switches or other control methods that can automatically turn off and on according to a preset schedule shall be installed for heaters and pump motors. Heaters and pump motors that have built-in time switches shall be in compliance with this section.


Exceptions:

  1. Where public health standards require 24-hour pump operation.
  2. Pumps that operate solar- and waste-heat-recovery pool heating systems.

Outdoor heated pools and outdoor permanent spas shall be provided with a vapor-retardant cover or other approved vapor-retardant means.

Exception: Where more than 75 percent of the energy for heating, computed over an operation season of not less than three calendar months, is from a heat pump or an on-site renewable energy system, covers or other vapor-retardant means shall not be required.

The energy consumption of electric-powered portable spas shall be controlled by the requirements of APSP-14.
Residential swimming pools and permanent residential spas that are accessory to detached one- and two-family dwellings and townhouses three stories or less in height above grade plane and that are available only to the household and its guests shall be in accordance with APSP 15.
Not less than 90 percent of the permanently installed lighting fixtures shall contain only high-efficacy lamps.
Fuel gas lighting systems shall not have continuously burning pilot lights.

R404.2 Electric Vehicle Charging Spaces ("EV Ready Spaces") Reserved

AMENDMENT
This section has been amended at the state or city level.
EV Ready spaces are not required for detached one- and two-family dwellings and multiple single-family dwellings (townhouses) not more than three stories above grade plane in height and their accessory structures not more than three stories above grade plane. All other occupancies otherwise directed to follow the provisions of 780 CMR 51.00: Massachusetts Residential Code must adhere to any EV requirements found in 780 CMR 1300.1(C405.10).

Section R405 Simulated Performance Alternative (Performance)

AMENDMENT
This section has been amended at the state or city level.

R405.1 Scope

AMENDMENT
This section has been amended at the state or city level.

R405.2 Mandatory Requirements

AMENDMENT
This section has been amended at the state or city level.

R405.3 Performance-Based Compliance

AMENDMENT
This section has been amended at the state or city level.

R405.4 Documentation

AMENDMENT
This section has been amended at the state or city level.

R405.4.1 Compliance Software Tools

AMENDMENT
This section has been amended at the state or city level.

R405.4.2 Compliance Report

AMENDMENT
This section has been amended at the state or city level.

R405.4.2.1 Compliance Report for Permit Application

AMENDMENT
This section has been amended at the state or city level.

R405.4.2.2 Compliance Report for Certificate of Occupancy

AMENDMENT
This section has been amended at the state or city level.

R405.4.3 Additional Documentation

AMENDMENT
This section has been amended at the state or city level.

R405.5 Calculation Procedure

AMENDMENT
This section has been amended at the state or city level.

R405.5.1 General

AMENDMENT
This section has been amended at the state or city level.

R405.5.2 Residence Specifications

AMENDMENT
This section has been amended at the state or city level.

R405.6 Calculation Software Tools

AMENDMENT
This section has been amended at the state or city level.

R405.6.1 Minimum Capabilities

AMENDMENT
This section has been amended at the state or city level.

R405.6.2 Specific Approval

AMENDMENT
This section has been amended at the state or city level.

R405.6.3 Input Values

AMENDMENT
This section has been amended at the state or city level.

Section R405 Reserved

AMENDMENT
This section has been amended at the state or city level.

R406.1 Scope

AMENDMENT
This section has been amended at the state or city level.
This section establishes criteria for compliance using an Energy Rating Index (ERI) analysis, or approved alternative energy performance rating methods.

R406.1.1 Approved Alternative Energy Performance Methods

AMENDMENT
This section has been amended at the state or city level.
The following rating threshold criteria are sufficient to demonstrate energy code compliance under R406 without calculation of a standard reference design. The mandatory provisions of subsection R406.2 also apply:
  1. ENERGY STAR Homes 3.1 Path. New buildings or additions to an existing building, building system or portion thereof shall be certified to conform to the ENERGY STAR Certified Homes, Version 3.1 standard.
  2. Passive House Institute US ("PHIUS") or Passive House Institute ("PHI") Approved Software. Projects pre-certified through PHIUS or PHI, with a certified Passive House Consultant or certified Passive House Designer verified "as-built" report demonstrating compliance with the PHIUS or PHI standard.
  3. Any other software approved by the Board of Building Regulations and Standards.

Compliance with this section requires that the provisions identified in Sections R401 through R404 indicated as "Mandatory" and Section R403.5.3 be met. The building thermal envelope shall be greater than or equal to levels of efficiency and Solar Heat Gain Coefficients in Table 402.1.1 or 402.1.3 of the 2009 International Energy Conservation Code.

Exception: Supply and return ducts not completely inside the building thermal envelope shall be insulated to an R-value of not less than R-6.

R406.3 Energy Rating Index

AMENDMENT
This section has been amended at the state or city level.

The Energy Rating Index (ERI) shall be determined in accordance with RESNET/ICC 301, the ERI Reference Design Ventilation rate shall be in accordance with Equation 4-1.

(Equation 4-1)

R406.4 ERI-Based Compliance

AMENDMENT
This section has been amended at the state or city level.

Compliance based on an ERI analysis requires that the rated design be shown to have an ERI less than or equal to the appropriate value indicated in Table R406.4 when compared to the ERI reference design for each dweilings unit prior to credit for onsite renewable electric generation.

TABLE R406.4

MAXIMUM ENERGY RATING INDEX

Maximum HERS Index Scorea, b
On-site Renewable Energy Application New Construction Whole House Renovations; Additions
None 55 65
Solar Electric Generation 60 70
Clean Space Heating 60 70
DHW 57 67
Solar Electric and Clean Space Heating 65 75
Solar Electric and DWH 62 72
Solar Electric, Clean Space Heating and DHW 67 77

R406.4.1 Trade-Off for Onsite Renewable Energy Systems

AMENDMENT
This section has been amended at the state or city level.
New construction following R406.3 or existing buildings and additions following IECC chapter 5 [RE] may use renewable energy trade-offs to increase the maximum allowable HERS rating for each unit separately served by any combination of the following:
  1. Solar Generation. Solar photovoltaic array rated at 2.5 kW or higher shall offset five HERS points.
  2. Clean Space Heating. Clean biomass heating system, solar thermal array, cold climate air source heat pump having rated coefficient of performance (COP) of at least 1.75 at 5°F, or geothermal heat pump, or a combination of these systems, operating as the primary heating system shall offset five HERS points.
  3. Renewable Domestic Hot Water Heating (DHW). Solar thermal array or heat pump for primary domestic hot water heating shall offset two HERS points.

R406.5 Verification by Approved Agency

AMENDMENT
This section has been amended at the state or city level.
Verification of compliance with section R406 shall be completed by an approved third party. For compliance using a HERS rating or Energy Star Homes 3.1 certification, verification of compliance shall be completed by the certified HERS rater. For compliance using PHIUS or PHI, verification of compliance shall be completed by a certified Passive House consultant.

R406.6 Documentation

AMENDMENT
This section has been amended at the state or city level.

R406.6.1 Compliance Software Tools

AMENDMENT
This section has been amended at the state or city level.

R406.6.2 Compliance Report

AMENDMENT
This section has been amended at the state or city level.

R406.6.3 Additional Documentation

AMENDMENT
This section has been amended at the state or city level.

R406.6.4 Specific Approval

AMENDMENT
This section has been amended at the state or city level.

R406.6.5 Input Values

AMENDMENT
This section has been amended at the state or city level.

R406.6 Documentation

AMENDMENT
This section has been amended at the state or city level.
Documentation of the software used and the parameters for the residential building shall be in accordance with Sections R406.6.1 through R406.6.4.

R406.6.1 Compliance Software Tools

AMENDMENT
This section has been amended at the state or city level.
If using the ERI or Energy Star Homes compliance path, software tools used for determining ERI shall be Approved Software Rating Tools in accordance with RESNET/ICC 301. Where calculations require input values not specified by Sections R402, R403, R404 and R405, those input values shall be taken from RESNET/ ICC 301. If using the Passive House compliance path, software tools for determining Passive House certification shall be approved software tools by PHIUS or PHI.

R406.6.2 ERI Documentation

AMENDMENT
This section has been amended at the state or city level.
Prior to the issuance of a building permit, the following items must be provided to the Building Official:
  1. A HERS compliance report which includes a proposed HERS index score of 55 or lower, or otherwise complies via renewable trade-offs;
  2. A description of the unit's energy features; and
  3. A statement that the rating index score is "based on plans"


Prior to the issuance of a certificate of occupancy, the following items must be provided to the Building official:
  1. A copy of the final certificate indicating that the HERS rating index score for each unit is verified to be 55 or less or otherwise complies via renewable trade-offs together with a completed HERS rater verified ENERGY STAR Thermal Enclosure System Rater Checklist.
  2. A copy of the certificate, as required by Section R401.3 for each unit listing the final HERS index score of the dwelling unit.

R406.6.3 Energy Star Homes, Version 3.1 Documentation

AMENDMENT
This section has been amended at the state or city level.
Prior to the issuance of a building permit the following items(s) must be provided to the Building Official:
  1. A copy of the preliminary HERS rating, based on plans
  2. A description of the unit's energy features; and
  3. A statement that the rating index score is "based on plans"
Prior to the issuance of a certificate of occupancy, the following items must be provided to the Building Official:
  1. A copy of the final ENERGY STAR Homes certificate;
  2. A copy of the certified final HERS rating; and
  3. A copy of the signed ENERGY STAR Thermal Enclosure System Rater Checklist.
  4. A copy of the certificate, as required by Section R401.3 for each unit listing the final HERS index score of the dwelling unit.

R406.6.4 Passive House Documentation

AMENDMENT
This section has been amended at the state or city level.
  1. If using PHIUS or PHI Passive House software, prior to the issuance of a building permit, the following items must be provided to the Building Official:
    1. A WUFI or PHPP compliance report which demonstrates project compliance with PHIUS+2018 (or newer) or PHI performance requirements;
    2. A statement that the WUFI or PHPP results are "based on plans";
    3. Evidence of precertification approval from PHIUS or PHI.
  2. Prior to the issuance of a certificate of occupancy, the following item(s) must be provided to the building official:
    1. An updated WUFI or PHPP compliance report which demonstrates project compliance with PHIUS+2018 (or newer) or PHI performance requirements;
    2. A copy of the Passive House Rater's test results;
    3. A statement that the WUFI or PHPP results are "based on 'as-buiit' conditions, incorporating the relevant test results and documented changes to equipment, materials, and assemblies that impact performance".

R406.7 Additional Efficiency Packages

AMENDMENT
This section has been amended at the state or city level.

R406.7.1 Requirements (Prescriptive)

AMENDMENT
This section has been amended at the state or city level.
Projects shall comply with at least one of the following:
  1. More efficient HVAC performance in accordance with Section R407.2
  2. Heat recovery ventilation (HRV) system or Energy recovery ventilation (ERV) system in accordance with Section R403.6.1. The Exception in R403.6.1 shall not be applied if used for compliance with this Section.
  3. High efficiency water heater or solar thermal hot water heater in accordance with Section R407.3

R406.7.2 More Efficient HVAC Performance

AMENDMENT
This section has been amended at the state or city level.
Primary heating equipment shall meet one of the following efficiency requirements:
  1. Gas, propane or oil-fired furnaces with a minimum AFUE of 95%
  2. Gas, propane or oil-fired boilers with a minimum AFUE of 95%
  3. Closed-loop ground source heat pumps with a minimum COP of 3.5
  4. Air-source heat pumps with a minimum HSPF of 10

R406.7.3 High Efficiency Water Heating or Solar Thermal Hot Water Heater

AMENDMENT
This section has been amended at the state or city level.
Hot water heating systems shall meet one of the following:
  1. Natural gas or propane water heating with a minimum Uniform Energy Factor (UEF) of 0.87 or electric heat pump hot water heater with a minimum UEF of 2.2. On-demand natural gas or propane water heaters shall not include any buffer tank or hot water storage capacity outside the water heater itself.
  2. A solar thermal hot water heating system with a minimum of 40 square feet of gross collection area. The solar hot water heating panels shall have a total solar resource fraction that is not less than 75%.
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