FireApproved

United States / Build / Fire-resistant roofing

Fire-resistant roofing

Program and model No adopted WUI code we can source here. IBHS Wildfire Prepared asks for the inspection measures, and the 2024 IWUIC model says the same floor.

National floor. A ZIP opens the same question at a place where a sourced instrument exists.

A fire-resistant roof is a covering tested on its deck to ASTM E108 or UL 790 and classed A, B or C; Class A is the most severe exposure. California CWUIC 504.2 requires a Class A assembly in mapped areas, IBHS Wildfire Prepared specifies a Class A covering, and Oregon R327, where adopted, sets a Class B floor and bans wood shakes and shingles. The Class A entry explains why the class belongs to the tested system, never the shingle.

What the sourced rules ask for

For national roofing, the national roofing requirement is 2018 IWUIC Class 1 Class A roof. On national roofing, it is shown as model code. Read the national roofing rule, then compare 21 matched national roofing products.

Review 19 national roofing place answers before choosing among national roofing records. The national roofing links keep the rule, products, and place differences together.

Find what applies near you

Enter a ZIP before browsing the complete evidence. Matching, inherited, and place-neutral records will move first; other places and unmapped application rows will fold into expandable groups. Nothing is removed. All 3 state rule sections remain available.

The rule

Model code “a roof assembly that complies with a Class A rating when tested in accordance with ASTM E 108 or UL 790”

2018 IWUIC Class 1 Class A roof. The unamended 2018 IWUIC specifies a Class A tested roof assembly for Class 1 ignition-resistant construction.

Products matching the model-code floor

Model code Product matches below are limited to roofing and trace to the named requirement.

Additional products matching the voluntary program

Voluntary program Product matches below are limited to roofing and trace to the named requirement.

Questions

What is the best fire-resistant roof?

The codes rank tested assemblies A, B and C, not materials by name. A Class A assembly, on the deck and underlayment its listing names, is the top class every book on this site recognises, and asphalt, metal, tile and slate each have Class A systems.

Do I have a Class A fire-rated roof?

The class is on the covering's ASTM E108 or UL 790 listing for the deck and underlayment installed, not on the shingle bundle. OSFM category 8180 lists non-wood covering assemblies by ID; the listing for your model on your deck is the answer.

Does Oregon require Class A?

Where R327 is adopted, the floor is a Class B-rated assembly equivalent. Wood shakes and wood shingles are not permitted. IBHS Essential and many community specs still ask for Class A. Both can be true on the same house.

Do I need an OSFM listed roof in Oregon?

OSFM category 8180 is a California listing of non-wood roof covering assemblies tested to ASTM E108 or UL 790. Listing is voluntary for most WUI products. Deschutes County says it will accept products from the OSFM WUI handbook when those products are shown on the drawings. That is local practice. It does not rewrite R327’s Class B floor. Confirm with the building official.

What about gutters?

Debris in gutters is an ember bed against the roof edge. IBHS Essential wants noncombustible gutters. Enhanced wants covers. Oregon R327, where adopted, requires both when gutters are provided. See the gutters category. This page does not list gutter products.

Where this answer differs

14 sourced rows

  • Model code 2018 IWUIC Class 1 Class A roof — The unamended 2018 IWUIC specifies a Class A tested roof assembly for Class 1 ignition-resistant construction.
  • Model code 2018 IWUIC Class 2 Class B roof — The unamended 2018 IWUIC specifies a Class B-or-better tested roof assembly for Class 2 ignition-resistant construction.
  • Model code 2018 IWUIC Class 3 Class C roof — The unamended 2018 IWUIC specifies a Class C-or-better tested roof assembly for Class 3 ignition-resistant construction.
  • Model code 2018 IWUIC roof-profile eave closure — The unamended 2018 IWUIC requires profile spaces at roof eave ends to block flame and ember entry or use the named cap-sheet path.
  • Model code 2018 IWUIC valley flashing — The unamended 2018 IWUIC specifies No. 26 galvanized corrosion-resistant metal valley flashing over a named full-width cap-sheet detail.
  • Model code 2021 IWUIC Class 1–2 Class A roof — The unamended 2021 IWUIC specifies a Class A tested roof assembly for Class 1 and Class 2 ignition-resistant construction.
  • Model code 2021 IWUIC Class 3 Class B roof — The unamended 2021 IWUIC specifies a Class B-or-better tested roof assembly for Class 3 ignition-resistant construction.
  • Model code 2021 IWUIC roof-profile eave closure — The unamended 2021 IWUIC requires profile spaces at roof eave ends to block flame and ember entry or use the named cap-sheet path.
  • Model code 2021 IWUIC valley flashing — The unamended 2021 IWUIC specifies No. 26 galvanized corrosion-resistant metal valley flashing over a named full-width cap-sheet detail.
  • Model code IWUIC Class 1–2 Class A roof — The unamended 2024 IWUIC model code specifies a Class A tested roof assembly for Class 1 and Class 2 ignition-resistant construction.
  • Model code IWUIC Class 3 Class B roof — The unamended 2024 IWUIC model code specifies a Class B-or-better tested roof assembly for Class 3 ignition-resistant construction.
  • Model code IWUIC roof-profile eave closure — The unamended 2024 IWUIC model code requires profile spaces at roof eave ends to block flame and ember entry or use the named cap-sheet path.
  • Model code IWUIC valley flashing — The unamended 2024 IWUIC model code specifies No. 26 galvanized corrosion-resistant metal valley flashing over a named full-width cap-sheet detail.
  • Voluntary program IBHS Base Class A roof covering — The current IBHS Base standard specifies a Class A roof covering tested to ASTM E108 or UL 790.