Quick Roofing Guide to the International Residential Code
Roof Online Staff
This page references the 2018 International Residential Code.
You may be looking for the Quick Roofing Guide to the International Building Code.
For a good guide to the entire IRC, consider getting DEWALT 2018 Residential Construction Codes: Complete Handbook. Link goes to the book’s Amazon page.*
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Chapter 1 Scope and Administration
See the full code for Chapter 1 on the ICC website.
See the full code for Chapter 1 on the UpCodes website.
Section R104 Duties and Powers of the Building Official
R104.10 Modifications
R104.11 Alternative materials, design and methods of construction and equipment
Section R105 Permits
R105.2 Work exempt from permit
R105.2.2 Repairs
Section R106 Construction Documents
Chapter 3 Building Planning
See the full code for Chapter 3 on the ICC website.
See the full code for Chapter 3 on the UpCodes website.
Section R301 Design Criteria
(Roof Online Note: This section mentions roofs over 100 times.)
R301.2 Climatic and geographic design criteria
R301.2.1 Wind design criteria
R301.2.2.2 Weights of materials
R301.6 Roof load
Section R302 Fire-Resistant Construction
R302.2.4 Parapets for townhouses
R302.2.5 Parapet construction
R302.2.6 Structural independence
Section R308 Glazing
R308.6 Skylights and sloped glazing
R308.6.8 Curbs for skylights
Section R316 Foam Plastic
R316.5 Specific requirements
R316.5.2 Roofing
R316.5.3 Attics
Section R324 Solar Energy Systems
R324.4 Rooftop-mounted photovoltaic systems
R324.5 Building-integrated photovoltaic systems
R324.6 Roof access and pathways
Chapter 4 Foundations
See the full code for Chapter 4 on the ICC website.
See the full code for Chapter 4 on the UpCodes website.
Section R406 Foundation Waterproofing and Dampproofing
Chapter 6 Wall Construction
See the full code for Chapter 6 on the ICC website.
See the full code for Chapter 6 on the UpCodes website.
(Roof Online Note: This chapter mentions roofs over 200 times, mostly having to do with wall construction requirements which ensure that the walls can support the loads imposed on them.)
Chapter 7 Wall Covering
See the full code for Chapter 7 on the ICC website.
See the full code for Chapter 7 on the UpCodes website.
Section R703 Exterior Covering
R703.3 Wall covering nominal thickness and attachments
R703.3.1 Soffit installation
R703.3.3 Fasteners
R703.4 Flashing
(Roof Online Note: Flashing requirements at wall and roof intersections, chimneys.)
R703.8 Anchored stone and masonry veneer, general
R703.8.2 Exterior veneer support
R703.8.2.2 Support by roof construction
Chapter 8 Roof-Ceiling Construction
See the full code for Chapter 8 on the ICC website.
See the full code for Chapter 8 on the UpCodes website.
(Roof Online Note: This chapter covers rafters, among other things. It mentions rafters over 200 times and includes rafter span tables. Also covers wood panel (plywood, OSB) roof sheathing requirements.)
Section R801 General
Section R802 Wood Roof Framing
Section R803 Roof Sheathing
R803.2 Wood Structural Panel Sheathing
(Roof Online Note: This subsection covers plywood and OSB sheathing. See Table R503.2.1.1 for minimum allowable panel thickness by span and load.)
Section R804 Cold-Formed Steel Roof Framing
Section R806 Roof Ventilation
Section R807 Attic Access
Chapter 9 Roof Assemblies
See the full code for Chapter 9 on the ICC website.
See the full code for Chapter 9 on the UpCodes website.
(Roof Online Note: This is the main roofing chapter of the code. In particular, note that the Section R905 subsections for each different type of roofing material cover deck requirements, slope, fasteners, underlayment, and flashing for that specific roof type.)
Section R902 Fire Classification
Section R903 Weather Protection
R903.2 Flashing
R903.3 Coping
R903.4 Roof drainage
Section R904 Materials
Section R905 Requirements for Roof Coverings
R905.1 Roof covering application
R905.1.1 Underlayment
R905.1.2 Ice barriers
(Roof Online Note: “Ice Barriers” covers the installation requirements for ice and water shield.)
R905.2 Asphalt shingles
R905.2.8 Flashing
R905.2.8.2 Valleys
R905.2.8.5 Drip Edge
R905.3 Clay and concrete tile
R905.4 Metal roof shingles
R905.5 Mineral-surfaced roll roofing
R905.6 Slate shingles
R905.7 Wood shingles
R905.8 Wood shakes
R905.9 Built-up roofs
R905.10 Metal roof panels
R905.11 Modified bitumen roofing
R905.12 Thermoset single-ply roofing
(Roof Online Note: This section covers EPDM roofing.)
R905.13 Thermoplastic single-ply roofing
(Roof Online Note: This section covers PVC and TPO roofing.)
R905.14 Sprayed polyurethane foam roofing
R905.15 Liquid-applied roofing
R905.16 Photovoltaic shingles
R905.17 Building-integrated Photovoltaic (BIPV) roof panels applied directly to the roof deck
Section R906 Roof Insulation
Section R907 Rooftop-Mounted Photovoltaic Panel Systems
Section R908 Reroofing
(Roof Online Note: This section covers the requirements for replacing an existing roof or installing a new roof over an old roof. It also tells you how many roofs (how many layers of roofing) you can put down on top of one another on a building and under what conditions.)
Chapter 10 Chimneys and Fireplaces
See the full code for Chapter 10 on the ICC website.
See the full code for Chapter 10 on the UpCodes website.
Section R1003 Masonry Chimneys
Section R1005 Factory-Built Chimneys
Chapter 11 [RE] Energy Efficiency
See the full code for Chapter 11 on the ICC website.
See the full code for Chapter 11 on the UpCodes website.
Section N1101 General
N1101.6 (R202) Defined terms
(Roof Online Note: We recommend reading this subsection first.)
N1101.7 (R301.1) Climate zones
TABLE N1101.7 (R301.1)
CLIMATE ZONES, MOISTURE REGIMES, AND WARM-HUMID DESIGNATIONS BY STATE, COUNTY AND TERRITORY
N1101.10 (R303.1) Identification
Section N1102 (R402) Building Thermal Envelope
N1102.1 (R402.1) General (Prescriptive)
N1102.1.2 (R402.1.2) Insulation and fenestration criteria
N1102.1.3 (R402.1.3) R -value computation
N1102.1.4 (R402.1.4) U- factor alternative
N1102.2 (R402.2) Specific insulation requirements (Prescriptive)
Section N1109 (R503) Alterations
N1109.1.1 (R503.1.1) Building envelope
Chapter 18 Chimneys and Vents
See the full code for Chapter 18 on the ICC website.
See the full code for Chapter 18 on the UpCodes website.
Section M1804 Vents
M1804.2 Termination
M1804.2.1 Through the roof
Section M1805 Masonry and Factory-Built Chimneys
Chapter 23 Solar Thermal Energy Systems
See the full code for Chapter 23 on the ICC website.
See the full code for Chapter 23 on the UpCodes website.
Section M2301 Solar Thermal Energy Systems
M2301.2 Design and installation
M2301.2.1 Access
M2301.2.2 Collectors and panels
M2301.2.2.1 Roof-mounted collectors
M2301.2.9 Roof and wall penetrations
Chapter 24 Fuel Gas
See the full code for Chapter 24 on the ICC website.
See the full code for Chapter 24 on the UpCodes website.
Section G2415 (404) Piping System Installation
G2415.9 (404.9) Above-ground piping outdoors
Section G2427 (503) Venting of Appliances
G2427.5 (503.5) Masonry, metal and factory-built chimneys
G2427.5.3 (503.5.4) Chimney termination
G2427.6 (503.6) Gas vents
G2427.6.4 (503.6.5) Gas vent terminations
G2427.6.6 (503.6.7) Roof terminations
G2427.7 (503.7) Single-wall metal pipe
G2427.7.3 (503.7.3) Termination
G2427.7.5 (503.7.5) Roof penetrations
Chapter 26 General Plumbing Requirements
See the full code for Chapter 26 on the ICC website.
See the full code for Chapter 26 on the UpCodes website.
Section P2607 Waterproofing of Openings
P2607.1 Pipes penetrating roofs
Chapter 29 Water Supply and Distribution
See the full code for Chapter 29 on the ICC website.
See the full code for Chapter 29 on the UpCodes website.
Chapter 31 Vents
See the full code for Chapter 31 on the ICC website.
See the full code for Chapter 31 on the UpCodes website.
Section P3103 Vent Terminals
P3103.1 Vent pipes terminating outdoors
P3103.3 Flashings and sealing
Chapter 44 Referenced Standards
See the full code for Chapter 44 on the ICC website.
See the full code for Chapter 44 on the UpCodes website.
(Roof Online Note: This chapter includes around 50 standards relevant to roofing.)
Appendix H - Patio Covers
See Appendix H on the ICC website.
See Appendix H on the UpCodes website.