Keeping current

A new edition of The NRCA Roofing Manual is now available

In January, NRCA published its revised edition of The NRCA Roofing Manual: Architectural Metal Flashing and Condensation and Air Leakage Control—2022. Following is a brief discussion of NRCA’s manual update process and the new information in this volume.

The NRCA Roofing Manual

NRCA published its first technical manual, A Manual of Roofing Practice, in 1969, which was superseded by five editions of The NRCA Roofing and Waterproofing Manual published in 1981, 1985, 1989, 1996 and 2001.

Since 2007, the four-volume set of The NRCA Roofing Manual has been published as an individual volume each year on a four-year repeating cycle. The current version of The NRCA Roofing Manual consists of four volumes:

  • The NRCA Roofing Manual: Architectural Metal Flashing and Condensation and Air Leakage Control—2022
  • The NRCA Roofing Manual: Steep-slope Roof Systems—2021
  • The NRCA Roofing Manual: Metal Panel and SPF Roof Systems—2020
  • The NRCA Roofing Manual: Membrane Roof Systems—2019

The manual represents NRCA’s in-depth, best industry practices and technical information concerning the design, materials and installation of quality roof systems.

2022 volume

The 2022 volume consists of three primary sections addressing architectural metal flashing, condensation and air leakage control, and appendixes.

The Architectural Metal Flashing Section, Chapter 1-Guidelines Applicable to Metal has been updated as follows:

  • Moving copper-coated stainless steel (Copper Plus) and zinc-tin-coated stainless steel (TCS II) to the Historic Metal section
  • Updating the metal tables to include thickness tolerances and other pertinent data
  • Adding information about color matching
  • Updating information about oil canning, including adding information about tension precision leveling intended to minimize oil canning

Chapter 2-Guidelines Applicable to Low-slope Roof Systems and Chapter 3-Guidelines Applicable to Steep-slope Roof Systems have been revised to include information about shimming irregular walls and roof edges for metal roof edge flashings, parapet saddle flashings, additional counterflashing options, and inside and outside corner joinery.

In Chapter 4-Construction Details, information has been added addressing fire-retardant-treated wood that contacts metal. Also, 14 of the 61 construction details have been revised.

In addition, two appendixes have been added to the section describing ANSI-SPRI/FM 4435/ES-1 testing of edge metal and ANSI/SPRI GT-1 testing of gutters.

In the Condensation and Air Leakage Control Section, ASHRAE’s new climate zone map has been added and references the most recent editions of ASHRAE standards, ASTM International standards, 2021 I-Codes and CAN/ULC standards.

In Chapter 3-Condensation Control and Ventilation of Steep-slope Roof Assemblies, additional vent options have been added.

In Chapter 4-Air Retarders for Roof Assemblies, NRCA updated its guidance for air retarders to be consistent with the 2021 International Energy Conservation Code®; ASHRAE 90.1-2019, “Energy Standard for Buildings Except Low-Rise Residential Buildings”; and ASHRAE 189.1-2020, “Standard for the Design of High-Performance Green Buildings,” all of which are substantially revised from their previous editions.

In the appendixes to this section, Appendix 2-U.S. Climate Zones, Appendix 3-Typical Thermal Properties of Building Materials and Appendix 6-Climate Design Information have been updated.

In the appendixes section, a new appendix, Appendix 1-Energy Code Compliance for Roof Systems, has been added describing energy code requirements for low- and steep-slope roof systems based on IECC 2021’s commercial and residential provisions. Also, Appendix 3-Considerations for Lightning Protection Systems, Appendix 5-Reference Organizations and Appendix 6-NRCA Technical Dictionary have been updated.

Getting it

NRCA members can view and download electronic versions of The NRCA Roofing Manual free of charge by accessing Also, for the first time, NRCA has published The NRCA Roofing Manual—2022 Set as a fully linked PDF of the manual’s four volumes, which allows for easy cross-referencing of sections, chapters and volumes.

Printed versions of the 2022 manual and other volumes of The NRCA Roofing Manual can be purchased by accessing

What’s next?

NRCA’s Manual Update Committee is reviewing, revising and updating The NRCA Roofing Manual: Membrane Roof Systems—2019 with the intention of publishing a new version in January 2023. If you wish to submit recommendations for revisions or additions to the manual, contact NRCA’s Technical Services Section at (847) 299-9070, option 4, or

NRCA remains committed to its more than 50-year precedent of maintaining its manual as a best practices technical reference concerning the design, materials and installation of quality roof systems. 

Callback: In the February issue, a comma was omitted from "Understanding R-value." The sentence should read: "Designers may want to use R-values other than those based on a 75 F mean temperature when determining vapor retarder placement, for cold storage buildings, or in cold or hot climates, for example." Professional Roofing regrets the error.

MARK S. GRAHAM is NRCA’s vice president of technical services.


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