A synthetic shingle fire class rating is earned by a tested roof assembly, not by the tile sitting in the bundle. The same composite slate can be Class A on one roof and Class C on the roof next door, because the underlayment, the deck material, the slope and the exposure were all part of the test. Two ICC-ES evaluation reports make the point plainly: per ESR-2119, DaVinci Slate is Class A over a single layer of No. 30 felt at 6 inch exposure, while per ESR-4756, Brava One Slate over that same felt is only Class C and needs a fire-resistant underlayment to reach Class A. Both tiles are polyethylene, both are sold as Class A products, and both statements are true.
By The Roofing Brief Team. Last reviewed: August 2026.
What a synthetic shingle fire class rating actually applies to
The class belongs to the assembly. ASTM E108 and its harmonized twin ANSI/UL 790 test a covering installed on a specified deck, over a specified underlayment, at a specified slope and exposure. The listing that comes out names all of those parts. Strip one out in the field and the roof you built is not the roof that was tested, which is why evaluation reports publish fire tables rather than a single class per product.
Codes reference the classification, not the brand. IRC Section R902.1 requires that Class A, B or C roofing be installed in jurisdictions designated by law as requiring it, or where the roof edge is less than 3 feet from a lot line, and that any roofing required to be listed be tested in accordance with ASTM E108 or UL 790. Our broader explainer on the Class A fire-rated roof covers how that plays out across every covering type. This page stays on synthetic and composite products, where the assembly dependence is sharpest and least advertised.
How ASTM E108 and UL 790 grade a roof assembly
ASTM E108 is an exterior fire exposure standard. Per ICC-ES, it runs five procedures: intermittent flame exposure, spread of flame, burning brand, flying brand and a rain test that weathers six decks through twelve one-week cycles before the fire tests are repeated. Class A and Class B specimens take a continuous gas flame for ten minutes in the spread-of-flame test; Class C takes four minutes.
The burning brand test is where assembly choices usually decide the outcome. Brands are built from Douglas fir for Classes A and B and from white pine for Class C, conditioned at 105 to 120 degrees Fahrenheit, then ignited at 1,630 degrees before being set on the test deck. A burning brand sitting on a polymer tile transfers heat downward for a long time, so what is directly under that tile, felt, a fire-resistant sheet, or a gypsum cover board, controls whether the deck ignites.
Nothing in that procedure measures how the roof and ceiling resist a fire starting inside the building. That is a separate fire-resistance rating with a separate number, and a Class A roof says nothing about it.
Same category, four listings, four different Class A recipes
Every row below comes from an evaluation report or manufacturer technical bulletin retrieved directly. Read it as the answer to one question: what has to be under the tile before the word Class A is accurate?
| Product | Assembly that earns Class A | Class over one layer No. 30 felt alone | Source document |
|---|---|---|---|
| DaVinci Slate (Westlake DaVinci Roofscapes) | Min. 15/32 in. plywood, 3:12 min. slope, one layer ASTM D226 Type II (No. 30) felt, 6 in. exposure | Class A at 6 in. exposure | ICC-ES ESR-2119 Table 1, System 1, reissued August 2023 |
| DaVinci Shake and Select Shake | No. 30 felt plus one layer ASTM D3909 mineral-surfaced cap sheet, or one layer GAF VersaShield, at 9 to 10 in. exposure | Not listed as Class A on felt alone | ICC-ES ESR-2119 Table 1, Systems 2 and 3 |
| Bellaforte Slate | One layer Eco Chief SolarHide-SRW (ESR-4035) over min. 15/32 in. plywood, 12 in. exposure | Not listed in any felt-only Class A system | ICC-ES ESR-2119 Table 1, System 5 |
| Brava One Slate and One Cedar Shake | One layer SolarHide-SRW (ESR-4035) or one layer ESP Low-E Therma-Sheet 4LMPX (ESR-3652), min. 15/32 in. plywood, 4:12 min. slope | Class C | ICC-ES ESR-4756 Table 1, Systems 1 to 6, issued November 2025 |
| EcoStar Empire Slate, Niagara Slate, Shake, Plus Shake | Min. 1/4 in. DensDeck gypsum board mechanically fastened, plus one ply Type 30 felt or GAF VersaShield, Atlas FR 50 or Layfast SBS TU43 | Class C (footnote 3: substituting felt for the cover board drops the assembly to Class C) | UL Evaluation Report ER18920-01, Table 1 |
| F-Wave REVIA vs REVIA XTM | REVIA needs a double layer of GAF Tiger Paw; REVIA XTM reaches the same class on a single layer | Not published as a felt-only assembly | F-Wave Technical Bulletin, Class A Fire Rating, Document Control No. CA012726TB |
Five manufacturers, five different definitions of the same two words. A specification that says “Class A composite slate” without naming the underlayment has not specified anything a building official can check. The head-to-head numbers behind two of these lines sit in our comparison of DaVinci vs Brava composite roofing.
Four things that quietly change the class on an otherwise identical roof
The variables below all appear inside published fire tables, and each one has moved a real product between classes. None of them are visible once the roof is finished, which is why field substitutions are the usual failure mode on composite jobs.
- Underlayment type. The clearest case: Brava One Slate is Class C over No. 30 felt and Class A over SolarHide-SRW or ESP Low-E Therma-Sheet 4LMPX, per ESR-4756 Table 1. Nothing about the tile changed.
- Deck material. In ESR-2119, one layer of SolarHide-SRW over minimum 15/32 in. plywood produces Class A for the whole DaVinci range (System 5). Move the same underlayment onto minimum 7/16 in. OSB and only DaVinci Slate stays Class A (System 6); Shake, Select Shake, Bellaforte and Province Slate are listed Class B (System 7).
- Exposure. ESR-2119 System 1 lists Class A over felt for DaVinci Slate at 6 in. exposure. Widen the course to 8 in. and the felt-only listing no longer covers it; the 6 to 8 in. range appears only in System 3, which adds a D3909 cap sheet.
- Layer count. F-Wave’s technical bulletin puts REVIA at Class A on a double layer of GAF Tiger Paw and REVIA XTM at Class A on a single layer. Same underlayment product, same class, different quantity.
Slope belongs on the list too, though it fails a job differently. ESR-2119 fire systems carry a 3:12 minimum; ESR-4756 fire systems carry a 4:12 minimum. A composite tile roof at 3.5:12 falls outside every Brava fire assembly listed.
How to read a “Class A when installed with” footnote
The footnote is not marketing hedging. It is a pointer to a table row, and the row is checkable in about five minutes. Work it in this order before the underlayment gets ordered, because that is the last moment the answer is free to change.
- Find the report number on the spec sheet or data sheet, for example ESR-2119, ESR-4756, or a UL Evaluation Report number such as ER18920-01.
- Pull the report itself from the issuing body rather than a distributor page, and check the date line. ESR-4756 was issued November 2025 and is subject to renewal November 2026. The ESR-2119 copy circulating on distributor sites is the August 2023 reissue. A report number on a brochure is not proof the report is current.
- Open the fire classification table, usually Table 1, and find the row that matches your exact product name, not the product family.
- Confirm all four assembly columns against your job: roof class, deck type and minimum thickness, minimum slope, and underlayment, then confirm the exposure column matches the coursing your crew will actually run.
- If the row you need uses a proprietary underlayment, open that product’s own report as well. GAF VersaShield sits under ESR-2053, reissued July 2026, and Eco Chief SolarHide-SRW under ESR-4035, reissued September 2025. Both are recognized as alternatives to ASTM D226 felt and as components of classified assemblies, and both have their own installation requirements.
- Save the PDF with the job file. If a plans examiner or an adjuster questions the class later, the table row is the answer.
A Class A synthetic roof is not automatically a wildfire-compliant roof
California treats wildfire exposure as a separate evaluation, and the two composite reports diverge here more sharply than anywhere else. The Brava supplement to ESR-4756 states that when installed as a Class A roof covering per CBC Section 705A, the products have been evaluated under CBC Chapter 7A and CRC Sections R337.5 and R902.1.3 for new buildings in any Fire Hazard Severity Zone within State Responsibility Areas or any Wildland-Urban Interface Fire Area.
The California supplement in the August 2023 reissue of ESR-2119 says the opposite in the same slot: the DaVinci products described in that report “have not been evaluated under Chapter 7A” and have not been evaluated under CRC Section R337 for those areas. That is a scope statement about the report, not a judgment about the tile, and manufacturers do add evaluations over time. It still means a designer in a WUI zone cannot treat a Class A listing as a Chapter 7A listing, and should confirm the current report before specifying.
Outside California, the parallel question is whichever local wildfire ordinance or state amendment applies. The base IRC only requires a classified roof where law designates it or the roof edge is within 3 feet of a lot line, so most of the pressure toward Class A on composite roofs comes from local rules, insurers, or the homeowner, not from the model code text.
UL 2218 impact class is a different test, and it belongs to the product
Impact class and fire class get quoted in the same breath and share the word “class,” which is where the confusion starts. UL 2218 is a steel ball drop test on the covering itself. Per the Insurance Institute for Business and Home Safety summary of the standard, the projectile is 1.25 inches in diameter for Class 1, 1.50 for Class 2, 1.75 for Class 3 and 2.00 inches for Class 4, dropped from the height that gives it the kinetic energy of a hailstone that size, with two strikes at the same location.
The practical difference: an impact class travels with the product, a fire class travels with the assembly. Swapping the underlayment can move a composite tile from Class A to Class C on fire and leave the UL 2218 class untouched. IBHS also notes that marks visible only on the top surface are not failures under UL 2218; the failure criterion is a crack or tear through the material.
| ASTM E108 / UL 790 fire class | UL 2218 impact class | |
|---|---|---|
| What is tested | The full assembly: covering, underlayment, deck, slope, exposure | The roof covering alone |
| Scale | Class A, B, C (A is highest) | Class 1 to 4 (4 is highest) |
| Changes with underlayment | Yes, routinely | No |
| Typical code driver | IRC R902.1, local wildfire rules, CBC Chapter 7A in California | Not a code requirement in the IRC; used by insurers |
| Where it is published | Fire classification table in the evaluation report | Manufacturer literature and UL certification listings |
Both DaVinci and Brava publish UL 2218 Class 4 for their composite tiles, so on hail the two lines are equivalent while their fire assemblies are not. For how Class 4 works on the asphalt side of the market, see impact resistant vs standard shingles.
What the insurance credit keys on, and what it does not
Insurance credits attach to the impact class, not the fire class, and the amount is not set by the standard. The Texas Department of Insurance states that roofing materials in shingle, tile, shake, metal panel or sheet form that pass UL Standard 2218 and are classified Class 1, 2, 3 or 4 may qualify for impact-resistant roofing credits, that the discount for each class is established by the insurance company on a company-by-company basis, and that the department does not endorse or recommend any roofing material. Texas also asks for a completed installation form, PC068, to document the product.
Practical reading for a composite roof: the Class 4 rating is often what a carrier asks for, requirements and credit sizes vary by state and by carrier, and some states leave the credit entirely optional. Ask the carrier what documentation it wants before the tear-off, since the label and product literature are easier to capture with the bundles on the ground. None of that turns on whether the roof is Class A, B or C on fire.
What to hand the building department and the insurer
Two different audiences, two different documents, and mixing them up is the most common paperwork problem on composite jobs. Keep both in the job file at closeout.
- Building department: the current evaluation report, with the fire table row you built to identified by system number, plus the underlayment’s own report if it is proprietary.
- Insurer: the UL 2218 impact classification documentation for the specific product, plus whatever installation form the state requires.
- Homeowner file: product name and color, exposure used, underlayment brand and layer count, and deck type. Those four facts are what a future adjuster, appraiser or roofer needs to reconstruct the class.
Weight rarely enters the fire conversation, but it decides whether a tile reroof is a covering swap or a framing project, which is covered in our analysis of composite roof tile weight and structural load, alongside the broader category overview of composite slate tile roofing.
Frequently asked questions
Is a synthetic shingle Class A on its own?
No. ASTM E108 and UL 790 classify an assembly, so the class depends on the covering plus the underlayment, deck, slope and exposure that were tested together. ICC-ES evaluation reports publish this as a fire classification table with several numbered systems per product. A tile described as Class A is accurate only when installed in one of those listed systems.
Why is Brava One Slate Class C over felt when DaVinci Slate can be Class A?
Because they were listed in different assemblies. Per ESR-4756 Table 1, Brava One Slate over one layer of ASTM D226 Type II (No. 30) felt is Class C, and reaches Class A over SolarHide-SRW or ESP Low-E Therma-Sheet 4LMPX. Per ESR-2119 Table 1 System 1, DaVinci Slate is listed Class A over that felt at 6 inch exposure on minimum 15/32 inch plywood.
Does a Class 4 impact rating mean the shingle is also Class A for fire?
No. UL 2218 Class 4 measures resistance to a 2.00 inch steel ball striking the covering twice in one spot. It says nothing about flame spread or burning brands, and it does not change with the underlayment. A composite tile can hold UL 2218 Class 4 and still sit in a Class C fire assembly if the wrong underlayment goes down.
Can changing the underlayment really change the fire class?
Yes, and it is the single most common cause of a downgrade. UL Evaluation Report ER18920-01 for EcoStar Empire tiles is explicit: substituting one ply of Type 30 asphaltic felt for the DensDeck cover board assembly drops any of the listed Class A assemblies to Class C. Same tile, same deck, same installer, different class.
Does a Class A composite roof meet California wildfire requirements?
Not automatically. Chapter 7A of the California Building Code and Section R337.5 of the Residential Code are a separate evaluation. The supplement to ESR-4756 states Brava One products were evaluated under Chapter 7A when installed as a Class A covering, while the August 2023 reissue of ESR-2119 states the DaVinci products in it had not been evaluated under Chapter 7A. Confirm the current report before specifying in a Fire Hazard Severity Zone.
Will a Class 4 synthetic roof lower my insurance premium?
It may, depending on state and carrier. The Texas Department of Insurance says materials classified Class 1 through 4 under UL 2218 may qualify for impact-resistant roofing credits, with the discount for each class set by each insurance company rather than by the state. Other states leave the credit optional. Ask the carrier what proof it accepts before the old roof comes off.
Sources
- ICC-ES Evaluation Report ESR-2119, Westlake DaVinci Roofscapes LLC, reissued August 2023, Table 1 Fire Classifications and California supplement.
- ICC-ES Evaluation Report ESR-4756, Wildhawk Investments LLC dba Brava Roof Tile, issued November 2025, Table 1 Fire Classification and California supplement.
- UL Evaluation Report ER18920-01, EcoStar Empire series synthetic composite roofing tiles, Table 1 and footnote 3.
- F-Wave Technical Bulletin, Class A Fire Rating, Document Control No. CA012726TB, Table 1.
- ICC-ES Evaluation Report ESR-2053, GAF VersaShield Fire-Resistant Roof Deck Protection, reissued July 2026.
- ICC-ES Evaluation Report ESR-4035, Eco Chief Products SolarHide-SRW Roofing Underlayment, reissued September 2025.
- ICC-ES, ASTM E108 Fire Tests for Roof Coverings, test procedure summary.
- International Residential Code Section R902.1, roof covering materials and classification.
- Insurance Institute for Business and Home Safety, Relative Impact Resistance of Asphalt Shingles, summary of UL 2218 impact tests.
- Texas Department of Insurance, products qualifying for impact-resistant roofing credits.