International Residential Code 2012 (IRC 2012)



Effective Use of the International Residential Code


Part I ‒ Administrative

Chapter 1 Scope and 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 Administration

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 G Swimming Pools, Spas and Hot Tubs

Appendix H Patio Covers

Appendix I Private Sewage Disposal

Appendix J Existing Buildings and Structures

Appendix K Sound Transmission

Appendix L Permit Fees

Appendix M Home Day Care—R-3 Occupancy

Appendix N Venting Methods

Appendix O Automatic Vehicular Gates

Appendix P Sizing of Water Piping System

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

(The provisions contained in this appendix are not mandatory unless specifically referenced in the adopting ordinance.)
Patio covers shall conform to the requirements of Sections AH101 through AH105.
Patio covers shall be permitted to be detached from or attached to dwelling units. Patio covers shall be used only for recreational, outdoor living purposes, and not as carports, garages, storage rooms or habitable rooms.
The following word and term shall, for the purposes of this appendix, have the meaning shown herein.
PATIO COVER. A structure with open or glazed walls which is used for recreational, outdoor living purposes associated with a dwelling unit.
Enclosure walls shall be permitted to be of any configuration, provided the open or glazed area of the longer wall and one additional wall is equal to at least 65 percent of the area below a minimum of 6 feet, 8 inches (2032 mm) of each wall, measured from the floor. Openings shall be permitted to be enclosed with the following:
1. Insect screening;
2. Approved translucent or transparent plastic not more than 0.125 inch (3.2 mm) in thickness;
3. Glass conforming to the provisions of Section R308; or
4. Any combination of the foregoing.
Exterior openings required for light and ventilation shall be permitted to open into a patio structure conforming to Section AH101, provided that the patio structure shall be unenclosed if such openings are serving as emergency egress or rescue openings from sleeping rooms. Where such exterior openings serve as an exit from the dwelling unit, the patio structure, unless unenclosed, shall be provided with exits conforming to the provisions of Section R311 of this code.
Patio covers shall be designed and constructed to sustain, within the stress limits of this code, all dead loads plus a minimum vertical live load of 10 pounds per square foot (0.48 kN/m2), except that snow loads shall be used where such snow loads exceed this minimum. Such covers shall be designed to resist the minimum wind loads set forth in Section R301.2.1.
In areas with a frostline depth of zero as specified in Table R301.2(1), a patio cover shall be permitted to be supported on a slab-on-grade without footings, provided the slab conforms to the provisions of Section R506, is not less than 3.5 inches (89 mm) thick and the columns do not support live and dead loads in excess of 750 pounds (3.34 kN) per column.
Screen enclosures in hurricane-prone regions shall be in accordance with the provisions of this Section.
Screen enclosures shall not be considered habitable spaces.
Screen enclosures shall have a ceiling height of not less than 7 feet (2134 mm).
The following word and term shall, for the purposes of this appendix, have the meaning shown herein.
SCREEN ENCLOSURE. A building or part thereof, in whole or in part self-supporting, and having walls of insect screening, and a roof of insect screening, plastic, aluminum or similar lightweight material.
Screen enclosures shall comply with Sections AH106.3.1 and AH106.3.2
Actual wall thickness of extruded aluminum members shall be not less than 0.040 inch (1.02 mm).
Screen density shall be a maximum of 20 threads per inch by 20 threads per inch mesh.
The structural design of screen enclosures shall comply with Sections AH106.4.1 through AH106.4.4.

TABLE AH106.4(1)

WALLBasic Wind Speed (mph)
Exposure Category Design Pressure (psf)
AdWindward and leeward walls (flow thru) and windward wall (nonflow thru) L/W = 0-112814101712191423162618
AdWindward and leeward walls (flow thru) and windward wall (nonflow thru) L/W = 213916111914221626183021
BeWindward: Nongable roof161220142417282032233726
BeWindward: Gable roof221627193223382744315036
For SI: 1 mile per hour = 0.44 m/s, 1 pound per square foot = 0.0479 kPa, 1 foot = 304.8 mm.
a. Values have been reduced for 0.77 importance factor in accordance with Section AH106.4.3.
b. Minimum design pressure shall be 10 psf in accordance with Section AH106.4.1.
c. Loads are applicable to screen enclosures with a mean roof height of 30 feet or less. For screen enclosures of different heights, the pressures given shall be adjusted by multiplying the table pressure by the adjustment factor given in Table AH106.4(2).
d. For Load Case A flow thru condition, the pressure given shall be applied simultaneously to both the upwind and downwind screen walls acting in the same direction as the wind. The structure shall also be analyzed for wind coming from the opposite direction. For the nonflow thru condition, the screen enclosure wall shall be analyzed for the load applied acting toward the interior of the enclosure.
e. For Load Case B, the table pressure multiplied by the projected frontal area of the screen enclosure is the total drag force, including drag on screen surfaces parallel to the wind, which must be transmitted to the ground. Use Load Case A for members directly supporting the screen surface perpendicular to the wind. Load Case B loads shall be applied only to structural members which carry wind loads from more than one surface.
f. The roof structure shall be analyzed for the pressure given occurring both upward and downward.

TABLE AH106.4(2)

Roof Height (feet)BC
For SI: 1 foot = 304.8 mm.
Structural members supporting screen enclosures shall be designed to support the minimum wind loads given in Tables AH106.4(1) and AH106.4(2). Where any value is less than 10 pounds per square foot (psf) (0.479 kN/m2) use 10 pounds per square feet (0.479 kN/m2).
For members supporting screen surfaces only, the total load deflection shall not exceed l/60. Screen surfaces shall be permitted to include a maximum of 25-percent solid flexible finishes.
The wind factor for screen enclosures shall be 0.77 in accordance with Section 6.5.5 of ASCE 7.
The minimum roof live load shall be 10 psf (0.479 kN/m2).
In areas with a frost line depth of zero, a screen enclosure shall be permitted to be supported on a concrete slab-on-grade without footings, provided the slab conforms to the provisions of Section R506, is not less than 31/2 inches (89 mm) thick and the columns do not support loads in excess of 750 pounds (3.36 kN) per column.