The National Roofing Contractors Association (NRCA) released The NRCA Roofing Manual: Steep-slope Roof Systems—2025, with information about the design, materials, and installation techniques applicable to steep-slope roof system applications. The new volume updates the 2021 volume with the same title and is a reference for contractors, architects, and roof consultants.
Notable changes include:
- Revised minimum wood panel roof deck sheathing thickness recommendations and OSB panel use in steep-slope roof deck recommendations
- New recommendations regarding decks made of materials other than wood and nailing substrate materials in steep-slope applications
- Revised recommendations for high-wind region steep-slope applications
- New and revised construction details
- Revised appendixes addressing steep-slope roof system compliance with International Building Code (IBC) 2024 and International Residential Code (IRC) 2024 provisions
- New appendixes addressing roofing slate repairs and Insurance Institute for Business & Home Safety’s (IBHS) FORTIFIED Roof program
The manual comprises five roof-covering type-specific sections and an appendixes section, including metal shingle roof systems. Each section is a self-contained reference manual and may be used by designers developing steep-slope roof system designs for specific projects.
The NRCA Roofing Manual: Steep-slope Roof Systems—2025 is used with other volumes of The NRCA Roofing Manual: The NRCA Roofing Manual: Metal Panel and SPF Roof Systems—2024; The NRCA Roofing Manual: Membrane Roof Systems—2023; and The NRCA Roofing Manual: Architectural Metal Flashing and Condensation and Air Leakage Control—2022.
In addition, The NRCA Construction Details: CAD Files—2025 has been updated to reflect construction details found in the 2025 manual boxed set, and The NRCA Roofing & Waterproofing Manual Anthology has been updated to include The NRCA Roofing Manual: Metal Panel and SPF Roof Systems—2021.
NRCA members can download the manual, and nonmembers may purchase the manual at nrca.net/manuals.