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• R905.6

  Slate Shingles

  • Slate goes on solid sheathing at 4:12 or steeper, meets ASTM C406, takes two fasteners, and laps 4 in (to 8:12), 3 in (to 20:12) or 2 in above.

  International Residential Code, 2024 · Chapter 9, Roof AssembliesRead the full text (opens UpCodes in a new tab)

• R803.2

  Wood Structural Panel Sheathing

  • Roof panels are graded and marked, exterior-rated if permanently exposed (Exposure 1 is fine underneath), span per the panel table, and overhang gable ends no more than 9 in without framing.

  International Residential Code, 2024 · Chapter 8, Roof-Ceiling ConstructionRead the full text (opens UpCodes in a new tab)

• R302.2.2

  Common Walls

  • A shared townhouse wall is 1-hour if sprinklered, 2-hour if not, rated from both sides, with no openings, ducts or equipment except water-filled sprinkler pipe.

  International Residential Code, 2024 · Chapter 3, Building PlanningRead the full text (opens UpCodes in a new tab)

• R503.2

  Wood Structural Panel Sheathing

  International Residential Code, 2024 · Chapter 5, FloorsRead the full text (opens UpCodes in a new tab)

• R603.9.2

  Determination of Minimum Length of Full-Height Sheathing

  International Residential Code, 2024 · Chapter 6, Wall ConstructionRead the full text (opens UpCodes in a new tab)

• R301.2.4.1

  Alternative Provisions

  International Residential Code, 2024 · Chapter 3, Building PlanningRead the full text (opens UpCodes in a new tab)

• R505.3.5

  Cutting and Notching

  • Never cut or notch the flanges or lips of steel floor members.

  International Residential Code, 2024 · Chapter 5, FloorsRead the full text (opens UpCodes in a new tab)

• R306.3.9

  Construction Documents

  International Residential Code, 2024 · Chapter 3, Building PlanningRead the full text (opens UpCodes in a new tab)

Searches all 4,276 IRC 2024 sections, 5,532 IBC 2024 sections and defined terms (Chapters 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33 so far) and each city's local rules as they are added. Section numbers and titles from the International Residential Code and International Building Code, 2024 editions, copyrighted by the International Code Council; the IRC's electrical chapters (34 to 43) follow NFPA 70, the National Electrical Code. Requirements are summarized in our words (IRC Chapters 3 to 43, IBC Chapters 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33); read the full text at the link on each result. Local values come from each city's published documents.