CODES

ADOPTS WITH AMENDMENTS:

International Residential Code 2012 (IRC 2012)

Copyright

Preface

Chapter 1 Administration

Part II ‒ Definitions

Chapter 2 Definitions

Part III ‒ Building Planning and Construction

Chapter 3 Building Planning

Chapter 4 Foundations

Chapter 5 Floors

Chapter 6 Wall Construction

Chapter 7 Wall Covering

Chapter 8 Roof-Ceiling Construction

Chapter 9 Roof Assemblies

Chapter 10 Chimneys and Fireplaces

Part IV ‒ Energy Conservation

Chapter 11 [RE] Energy Efficiency

Part V ‒ Mechanical

Chapter 12 Mechanical Administration

Chapter 13 General Mechanical System Requirements

Chapter 14 Heating and Cooling Equipment and Appliances

Chapter 15 Exhaust Systems

Chapter 16 Duct Systems

Chapter 17 Combustion Air

Chapter 18 Chimneys and Vents

Chapter 19 Special Appliances, Equipment and Systems

Chapter 20 Boilers and Water Heaters

Chapter 21 Hydronic Piping

Chapter 22 Special Piping and Storage Systems

Chapter 23 Solar Energy Systems

Part VI ‒ Fuel Gas

Chapter 24 Fuel Gas

Part VII ‒ Plumbing

Chapter 25 Plumbing Administration

Chapter 26 General Plumbing Requirements

Chapter 27 Plumbing Fixtures

Chapter 28 Water Heaters

Chapter 29 Water Supply and Distribution

Chapter 30 Sanitary Drainage

Chapter 31 Vents

Chapter 32 Traps

Chapter 33 Storm Drainage

Part VIII ‒ Electrical

Chapter 34 General Requirements

Chapter 35 Electrical Definitions

Chapter 36 Services

Chapter 37 Branch Circuit and Feeder Requirements

Chapter 38 Wiring Methods

Chapter 39 Power and Lighting Distribution

Chapter 40 Devices and Luminaires

Chapter 41 Appliance Installation

Chapter 42 Swimming Pools

Chapter 43 Class 2 Remote-Control, Signaling and Power-Limited Circuits

Part IX ‒ Referenced Standards

Chapter 44 Referenced Standards

Appendix A Sizing and Capacities of Gas Piping

Appendix B Sizing of Venting Systems Serving Appliances Equipped With Draft Hoods, Category I Appliances, and Appliances Listed for Use With Type B Vents

Appendix C Exit Terminals of Mechanical Draft and Direct-Vent Venting Systems

Appendix D Recommended Procedure for Safety Inspection of an Existing Appliance Installation

Appendix E Manufactured Housing Used as Dwellings

Appendix F Radon Control Methods

Appendix H Patio Covers

Appendix K Sound Transmission

Appendix N Venting Methods

Appendix P Sizing of Water Piping System

Appendix Q Icc International Residential Code Electrical Provisions/ National Electrical Code Cross Reference

The provisions of this chapter shall govern the installation of mechanical systems not specifically covered in other chapters applicable to mechanical systems. Installations of mechanical appliances, equipment and systems not addressed by this code shall comply with the applicable provisions of the International Mechanical Code and the International Fuel Gas Code.
In flood hazard areas as established by Table R301.2(1), mechanical appliances, equipment and systems shall be located or installed in accordance with Section R322.1.6.
Each length of pipe and tubing and each pipe fitting utilized in a mechanical system shall bear the identification of the manufacturer.
All materials used shall be installed in strict accordance with the standards under which the materials are accepted and approved. In the absence of such installation procedures, the manufacturer’s instructions shall be followed. Where the requirements of referenced standards or manufacturer’s instructions do not conform to minimum provisions of this code, the provisions of this code shall apply.
Plastic pipe, fittings and components shall be third-party certified as conforming to NSF 14.

Piping, tubing and fittings shall comply with the applicable referenced standards, specifications and performance criteria of this code and shall be identified in accordance with Section M1301.2. Piping, tubing and fittings shall either be tested by an approved third-party testing agency or certified by an approved third-party certification agency.

Appliances regulated by this code shall be listed and labeled for the application in which they are installed and used, unless otherwise approved in accordance with Section R104.11.

A permanent factory-applied nameplate(s) shall be affixed to appliances on which shall appear, in legible lettering, the manufacturer’s name or trademark, the model number, a serial number and the seal or mark of the testing agency. A label shall also include the following:

  1. Electrical appliances. Electrical rating in volts, amperes and motor phase; identification of individual electrical components in volts, amperes or watts and motor phase; and in Btu/h (W) output and required clearances.
  2. Absorption units. Hourly rating in Btu/h (W), minimum hourly rating for units having step or automatic modulating controls, type of fuel, type of refrigerant, cooling capacity in Btu/h (W) and required clearances.
  3. Fuel-burning units. Hourly rating in Btu/h (W), type of fuel approved for use with the appliance and required clearances.
  4. Electric comfort-heating appliances. The electric rating in volts, amperes and phase; Btu/h (W) output rating; individual marking for each electrical component in amperes or watts, volts and phase; and required clearances from combustibles.
  5. Maintenance instructions. Required regular maintenance actions and title or publication number for the operation and maintenance manual for that particular model and type of product.
Fuel-fired appliances shall be designed for use with the type of fuel to which they will be connected and the altitude at which they are installed. Appliances that comprise parts of the building mechanical system shall not be converted for the use of a different fuel, except where approved and converted in accordance with the manufacturer’s instructions. The fuel input rate shall not be increased or decreased beyond the limit rating for the altitude at which the appliance is installed.
Appliances shall be accessible for inspection, service, repair and replacement without removing permanent construction, other appliances, or any other piping or ducts not connected to the appliance being inspected, serviced, repaired or replaced. A level working space at least 30 inches deep and 30 inches wide (762 mm by 762 mm) shall be provided in front of the control side to service an appliance. Installation of room heaters shall be permitted with at least an 18-inch (457 mm) working space. A platform shall not be required for room heaters.

Furnaces and air handlers within compartments or alcoves shall have a minimum working space clearance of 3 inches (76 mm) along the sides, back and top with a total width of the enclosing space being at least 12 inches (305 mm) wider than the furnace or air handler. Furnaces having a firebox open to the atmosphere shall have at least a 6-inch (152 mm) working space along the front combustion chamber side. Combustion air openings at the rear or side of the compartment shall comply with the requirements of Chapter 17.

Exception: This section shall not apply to replacement appliances installed in existing compartments and alcoves where the working space clearances are in accordance with the equipment or appliance manufacturer’s installation instructions.

Appliances installed in a compartment, alcove, basement or similar space shall be accessed by an opening or door and an unobstructed passageway measuring not less than 24 inches (610 mm) wide and large enough to allow removal of the largest appliance in the space, provided there is a level service space of not less than 30 inches (762 mm) deep and the height of the appliance, but not less than 30 inches (762 mm), at the front or service side of the appliance with the door open.

Attics containing appliances shall be provided with an opening and a clear and unobstructed passageway large enough to allow removal of the largest appliance, but not less than 30 inches (762 mm) high and 22 inches (559 mm) wide and not more than 20 feet (6096 mm) long measured along the centerline of the passageway from the opening to the appliance. The passageway shall have continuous solid flooring in accordance with Chapter 5 not less than 24 inches (610 mm) wide. A level service space at least 30 inches (762 mm) deep and 30 inches (762 mm) wide shall be present along all sides of the appliance where access is required. The clear access opening dimensions shall be a minimum of 20 inches by 30 inches (508 mm by 762 mm), and large enough to allow removal of the largest appliance.

Exceptions:

  1. The passageway and level service space are not required where the appliance can be serviced and removed through the required opening.
  2. Where the passageway is unobstructed and not less than 6 feet (1829 mm) high and 22 inches (559 mm) wide for its entire length, the passageway shall be not more than 50 feet (15 250 mm) long.
A luminaire controlled by a switch located at the required passageway opening and a receptacle outlet shall be installed at or near the appliance location in accordance with Chapter 39.

Underfloor spaces containing appliances shall be provided with an unobstructed passageway large enough to remove the largest appliance, but not less than 30 inches (762 mm) high and 22 inches (559 mm) wide, nor more than 20 feet (6096 mm) long measured along the centerline of the passageway from the opening to the appliance. A level service space at least 30 inches (762 mm) deep and 30 inches (762 mm) wide shall be present at the front or service side of the appliance. If the depth of the passageway or the service space exceeds 12 inches (305 mm) below the adjoining grade, the walls of the passageway shall be lined with concrete or masonry extending 4 inches (102 mm) above the adjoining grade in accordance with Chapter 4. The rough-framed access opening dimensions shall be a minimum of 22 inches by 30 inches (559 mm by 762 mm), and large enough to remove the largest appliance.

Exceptions:

  1. The passageway is not required where the level service space is present when the access is open, and the appliance can be serviced and removed through the required opening.
  2. Where the passageway is unobstructed and not less than 6 feet high (1929 mm) and 22 inches (559 mm) wide for its entire length, the passageway shall not be limited in length.
Equipment and appliances supported from the ground shall be level and firmly supported on a concrete slab or other approved material extending not less than 3 inches (76 mm) above the adjoining ground. Such support shall be in accordance with the manufacturer’s installation instructions. Appliances suspended from the floor shall have a clearance of not less than 6 inches (152 mm) from the ground.
Excavations for appliance installations shall extend to a depth of 6 inches (152 mm) below the appliance and 12 inches (305 mm) on all sides, except that the control side shall have a clearance of 30 inches (762 mm).
A luminaire controlled by a switch located at the required passageway opening and a receptacle outlet shall be installed at or near the appliance location in accordance with Chapter 39.

Appliances shall be installed with the clearances from unprotected combustible materials as indicated on the appliance label and in the manufacturer’s installation instructions.

Note: “A” equals the required clearance with no protection. “B” equals the reduced clearance permitted in accordance with Table M1306.2. The protection applied to the construction using combustible material shall extend far enough in each direction to make “C” equal to “A.”

FIGURE M1306.1

REDUCED CLEARANCE DIAGRAM

Reduction of clearances shall be in accordance with the appliance manufacturer’s instructions and Table M1306.2. Forms of protection with ventilated air space shall conform to the following requirements:

  1. Not less than 1-inch (25 mm) air space shall be provided between the protection and combustible wall surface.
  2. Air circulation shall be provided by having edges of the wall protection open at least 1 inch (25 mm).
  3. If the wall protection is mounted on a single flat wall away from corners, air circulation shall be provided by having the bottom and top edges, or the side and top edges open at least 1 inch (25 mm).
  4. Wall protection covering two walls in a corner shall be open at the bottom and top edges at least 1 inch (25 mm).

TABLE M1306.2

REDUCTION OF CLEARANCES WITH SPECIFIED FORMS OF PROTECTIONa, c, d, e, f, g, h, I, j, k, l

TYPE OF PROTECTION APPLIED TO
AND COVERING ALL SURFACES OF
COMBUSTIBLE MATERIAL WITHIN THE
DISTANCE SPECIFIED AS THE
REQUIRED CLEARANCE WITH NO
PROTECTION (See Figures M1306.1 and
M1306.2)
WHERE THE REQUIRED CLEARANCE WITH NO PROTECTION FROM APPLIANCE,
VENT CONNECTOR, OR SINGLE WALL METAL PIPE IS:
36 inches18 inches12 inches9 inches6 inches
Allowable clearances with specified protection (Inches)b
Use column 1 for clearances above an appliance or horizontal connector.
Use column 2 for clearances from an appliance, vertical connector and single-wall metal pipe.
Above
column 1
Sides and
rear
column 2
Above
column 1
Sides and
rear
column 2
Above
column 1
Sides and
rear
column 2
Above
column 1
Sides and
rear
column 2
Above
column 1
Sides and
rear
column 2
31/2-inch-thick masonry wall without
ventilated air space
2412965
1/2-inch insulation board over 1-inch
glass fiber or mineral wool batts
2418129966543
Galvanized sheet steel having a minimum
thickness of 0.0236-inch (No.
24 gage) over 1-inch glass fiber or
mineral wool batts reinforced with
wire or rear face with a ventilated air
space
181296645333
31/2-inch-thick masonry wall with
ventilated air space
126666
Galvanized sheet steel having a minimum
thickness of 0.0236-inch (No.
24 gage) with a ventilated air space
1-inch off the combustible assembly
181296645332
1/2-inch-thick insulation board with
ventilated air space
181296645333
Galvanized sheet steel having a minimum
thickness of 0.0236-inch (No.
24 gage) with ventilated air space
over 24 gage sheet steel with a
ventilated space
181296645333
1-inch glass fiber or mineral wool
batts sandwiched between two
sheets of galvanized sheet steel having
a minimum thickness of 0.0236
-inch (No. 24 gage) with a ventilated
air space
181296645333

For SI: 1 inch = 25.4 mm, 1 pound per cubic foot = 16.019 kg/m3, °C = [(°F)-32/1.8], 1 Btu/(h × ft2 × °F/in.) = 0.001442299 (W/cm2 × °C/cm).

  1. Reduction of clearances from combustible materials shall not interfere with combustion air, draft hood clearance and relief, and accessibility of servicing.
  2. Clearances shall be measured from the surface of the heat producing appliance or equipment to the outer surface of the combustible material or combustible assembly.
  3. Spacers and ties shall be of noncombustible material. No spacer or tie shall be used directly opposite appliance or connector.
  4. Where all clearance reduction systems use a ventilated air space, adequate provision for air circulation shall be provided as described. (See Figures M1306.1 and M1306.2.)
  5. There shall be at least 1 inch between clearance reduction systems and combustible walls and ceilings for reduction systems using ventilated air space.
  6. If a wall protector is mounted on a single flat wall away from corners, adequate air circulation shall be permitted to be provided by leaving only the bottom and top edges or only the side and top edges open with at least a 1-inch air gap.
  7. Mineral wool and glass fiber batts (blanket or board) shall have a minimum density of 8 pounds per cubic foot and a minimum melting point of 1,500°F.
  8. Insulation material used as part of a clearance reduction system shall have a thermal conductivity of 1.0 Btu inch per square foot per hour °F or less. Insulation board shall be formed of noncombustible material.
  9. There shall be at least 1 inch between the appliance and the protector. In no case shall the clearance between the appliance and the combustible surface be reduced below that allowed in this table.
  10. All clearances and thicknesses are minimum; larger clearances and thicknesses are acceptable.
  11. Listed single-wall connectors shall be permitted to be installed in accordance with the terms of their listing and the manufacturer’s instructions.
  12. For limitations on clearance reduction for solid-fuel-burning appliances see Section M1306.2.1.

For SI: 1 inch = 25.4 mm.

FIGURE M1306.2

WALL PROTECTOR CLEARANCE REDUCTION SYSTEM

Table M1306.2 shall not be used to reduce the clearance required for solid-fuel appliances listed for installation with minimum clearances of 12 inches (305 mm) or less. For appliances listed for installation with minimum clearances greater than 12 inches (305 mm), Table M1306.2 shall not be used to reduce the clearance to less than 12 inches (305 mm).
Installation of appliances shall conform to the conditions of their listing and label and the manufacturer’s installation instructions. The manufacturer’s operating and installation instructions shall remain attached to the appliance.
Appliances designed to be fixed in position shall be fastened or anchored in an approved manner. In Seismic Design Categories D1 and D2, water heaters shall be anchored or strapped to resist horizontal displacement caused by earthquake motion. Strapping shall be at points within the upper one-third and lower one-third of the appliance’s vertical dimensions. At the lower point, the strapping shall maintain a minimum distance of 4 inches (102 mm) above the controls.

Appliances having an ignition source shall be elevated such that the source of ignition is not less than 18 inches (457 mm) above the floor in garages. For the purpose of this section, rooms or spaces that are not part of the living space of a dwelling unit and that communicate with a private garage through openings shall be considered to be part of the garage.

Exception: Elevation of the ignition source is not required for appliances that are listed as flammable vapor ignition resistant.

Appliances shall not be installed in a location subject to vehicle damage except where protected by approved barriers.
Ventilation shall be required in accordance with Section M1307.4.1, M1307.4.2 or M1307.4.3 in private garages that contain hydrogen-generating appliances or refueling systems. For the purpose of this section, rooms or spaces that are not part of the living space of a dwelling unit and that communicate directly with a private garage through openings shall be considered to be part of the private garage.
Indoor locations intended for hydrogen-generating or refueling operations shall be limited to a maximum floor area of 850 square feet (79 m2) and shall communicate with the outdoors in accordance with Sections M1307.4.1.1 and M1307.4.1.2. The maximum rated output capacity of hydrogen-generating appliances shall not exceed 4 standard cubic feet per minute (1.9 L/s) of hydrogen for each 250 square feet (23 m2) of floor area in such spaces. The minimum cross-sectional dimension of air openings shall be 3 inches (76 mm). Where ducts are used, they shall be of the same cross-sectional area as the free area of the openings to which they connect. In those locations, equipment and appliances having an ignition source shall be located so that the source of ignition is not within 12 inches (305 mm) of the ceiling.
Two permanent openings shall be constructed within the garage. The upper opening shall be located entirely within 12 inches (305 mm) of the ceiling of the garage. The lower opening shall be located entirely within 12 inches (305 mm) of the floor of the garage. Both openings shall be constructed in the same exterior wall. The openings shall communicate directly with the outdoors and shall have a minimum free area of 1/2 square foot per 1,000 cubic feet (1.7 m2/1000 m3) of garage volume.
In calculating free area required by Section M1307.4.1, the required size of openings shall be based on the net free area of each opening. If the free area through a design of louver or grille is known, it shall be used in calculating the size opening required to provide the free area specified. If the design and free area are not known, it shall be assumed that wood louvers will have a 25-percent free area and metal louvers and grilles will have a 75-percent free area. Louvers and grilles shall be fixed in the open position.
Indoor locations intended for hydrogen-generating or refueling operations shall be ventilated in accordance with Section 502.16 of the International Mechanical Code. In these locations, equipment and appliances having an ignition source shall be located so that the source of ignition is below the mechanical ventilation outlet(s).
As an alternative to the provisions of Sections M1307.4.1 and M1307.4.2, the necessary supply of air for ventilation and dilution of flammable gases shall be provided by an approved engineered system.
Electrical appliances shall be installed in accordance with Chapters 14, 15, 19, 20 and 34 through 43 of this code.
Potable water and drainage system connections to equipment and appliances regulated by this code shall be in accordance with Chapters 29 and 30.
Wood-framed structural members shall be drilled, notched or altered in accordance with the provisions of Sections R502.8, R602.6, R602.6.1 and R802.7. Holes in load-bearing members of cold-formed steel light-frame construction shall be permitted only in accordance with Sections R505.2.5, R603.2.5 and R804.2.5. In accordance with the provisions of Sections R505.3.5, R603.3.4 and R804.3.4, cutting and notching of flanges and lips of load-bearing members of cold-formed steel light frame construction shall not be permitted. Structural insulated panels (SIPs) shall be drilled and notched or altered in accordance with the provisions of Section R613.7.
In concealed locations where piping, other than cast-iron or galvanized steel, is installed through holes or notches in studs, joists, rafters or similar members less than 1.5 inches (38 mm) from the nearest edge of the member, the pipe shall be protected by shield plates. Protective steel shield plates having a minimum thickness of 0.0575-inch (1.463 mm) (No. 16 gage), shall cover the area of the pipe where the member is notched or bored, and shall extend a minimum of 2 inches (51 mm) above sole plates and below top plates.
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