jaspector
§ Chapter 9 IRC 2024

Roof Assemblies

8 entries from Chapter 9 of IRC 2024, organized by section number. Each entry covers what the code requires, why it exists, what inspectors look for, and common mistakes.

§ 01   Sections

All 8 entries.

Sorted by section number. Click any row for the full entry — answer, requirements, edition diff, related sections.

IRC 2024 Roof Deck Sheathing: OSB and Plywood Thickness for Different Rafter Spacing
R803.1
What thickness of OSB or plywood does IRC 2024 require for roof deck sheathing based on rafter spacing?
IRC 2024 Roof Ventilation: 1-to-150 Ratio for Attic Ventilation
R806
What ventilation ratio does IRC 2024 require for attic spaces, and how do intake and exhaust vents need to be balanced?
IRC 2024 Chimney Cricket: Required When Chimney Is 30 Inches or Wider
R903.2.2
When does IRC 2024 require a chimney cricket (saddle), and how must it be constructed and flashed?
IRC 2024 Roof Slope: Minimum Pitch by Roofing Material Type
R905
What is the minimum roof slope required by IRC 2024 for asphalt shingles, metal roofing, tile, and low-slope applications?
IRC 2024 Asphalt Shingle Installation: Nailing, Overlap, and Ice Dam Requirements
R905.2
How many nails does IRC 2024 require per asphalt shingle, and what are the overlap and ice dam shield requirements?
IRC 2024 Roof Underlayment: #15 Felt vs Synthetic Felt Requirements
R905.2.3
Does IRC 2024 require #15 felt or synthetic underlayment under asphalt shingles, and what are the overlap and low-slope requirements?
IRC 2024 Valley Flashing: Open vs Closed Valley Installation Methods
R905.2.8
What does IRC 2024 require for valley flashing, and what are the differences between open, closed-cut, and woven valley methods?
IRC 2024 Drip Edge: Required at Eaves and Rakes Under Asphalt Shingles
R905.2.8.5
Does IRC 2024 require drip edge flashing on asphalt shingle roofs, and how does the installation differ at eaves versus rakes?