For homeowners and property buyers reading a proposal for a synthetic covering

“Composite” is a category name, not a material.

Steep-slope roofs · single-family

Behind the word are moulded polymer, rubber and resin products from different manufacturers with different chemistries and different track records. The only things they reliably share are the marketing and the shape.

30-second answer

What is composite roofing, and how do you judge a product category that is younger than the warranty it sells?

“Composite” describes moulded polymer, rubber or resin units, usually with fillers and other additives, shaped to imitate slate or shake. It is a category name, not a specification: the model code has no section for it, so each product enters as an alternative material carrying its own evaluation report. Read that report. It states what was actually tested, and what was not.

Stop — immediate hazard

If roof units are lifting, sliding, or coming off, keep people and vehicles clear of the ground below.

A moulded roof unit that has released is a falling object, and the next gust releases the next one. Nothing on this page is more urgent than getting people out from underneath it.

Do not climb up to look. Every check described on this page is done from the ground, from a window, from photographs, or from a document. OSHA records that “falls are the leading cause of death for workers engaged in residential construction,” and requires conventional fall protection for those workers at six feet or more above lower levels. Those are trained people with harnesses.

Move cars and keep the area beneath the affected slope clear, then call a roofing contractor. If water is running from or near a light fitting, a fan, a smoke alarm, or an electrical panel, do not touch it — leave the room and call a licensed electrician or your electric utility. If a ceiling is sagging or bulging, stay out from under it and call 911.

Learning paths and saved lessons

At a glance

The short versionSection link

Everything in this panel is a statement about documents, not a statement about how long a roof lasts. That is deliberate: the documents are checkable today, and the service life is not.

What the word covers: Moulded polymer, rubber, or resin units, usually with filler, shaped to imitate slate or shakeNot one material. The specification systems used by architects call them plastic roof tiles (CSI 07 32 26), plastic shakes (07 31 53), or composite rubber shingles (07 31 33) — three different sections for three different chemistries.
Where the model code puts it: Nowhere2024 IRC section R905 gives prescriptive requirements for asphalt shingles, clay and concrete tile, metal roof shingles, mineral-surfaced roll roofing, slate, wood shingles, wood shakes, built-up roofs, metal roof panels, modified bitumen, thermoset and thermoplastic single-ply, sprayed polyurethane foam, and building-integrated photovoltaics. Polymer composites are not among them.
How it gets onto a roof legally: As an alternative material, on the strength of an evaluation reportThe model codes let a building official accept a material the code does not prescribe, if it is found equivalent in quality, strength, durability, effectiveness, fire resistance and safety. That acceptance is the official's to give, and it is normally given for a specific project.
What it is evaluated against: ICC-ES AC07, Acceptance Criteria for Special Roofing Systems, dated February 2014All three evaluation reports read for this page cite AC07. None cites a consensus material specification of the kind ASTM C406 gives slate or ASTM D3462 gives asphalt shingles, because for this class of product there is not one.
The weathering evidence behind the criterion: Xenon-arc accelerated exposure (ASTM G155) and temperature cyclingLaboratory exposure, measured in lamp hours. NIST states plainly that turning that into a service-life prediction is difficult, because of the differences in ultraviolet spectrum, ultraviolet intensity, and moisture and temperature variability between a chamber and a roof.
Longest independently measured outdoor weathering available: Three yearsThe Cool Roof Rating Council publishes initial and three-year-aged solar reflectance and thermal emittance, measured after real exposure at approved test farms in Arizona, Ohio and Florida. Three years is not a criticism of the CRRC. It is the length of the longest public outdoor measurement there is.
Installed weight, in the two reports that state one: About 210–340 lb per roofing squareProduct-specific, and stated in the evaluation report in pounds per square foot or per 100 square feet. The third report read for this page states no weight at all. It is not a category figure and it is not a substitute for reading the report for the product in front of you.
Re-roofing: All three reports require the existing covering and underlayment to be removed firstNone of them contemplates going over an existing roof. A proposal that offers to lay composite over the old covering is outside the conditions of use those reports set.
Service life: Not a number this page will publishA warranty term is a commercial promise. A planning range has to rest on observed service, and for this category the observed service is shorter than the promises. What can be said honestly is on this page; a number cannot.

Tradeoffs

This page's advice — buy on the documents rather than the warranty — and where that advice is wrongSection link

The position taken here is that the evaluation report, the fire listing and the impact listing tell you more than any brochure, and that a long warranty on a young category is the weakest evidence on the table. There are situations where that is the wrong emphasis.

Best when

The building cannot carry natural slate or clay tile, and the choice is between an imitation and giving up the appearance entirely. This is the case composite was invented for, and it is a good one.
A homeowners' association, a design review board, or a historic district requires a slate or shake appearance that asphalt cannot produce.
The roof is a straightforward steep-slope plane at 4:12 or steeper, with no low-slope sections the product's report excludes.
You are prepared to require the specific tested assembly — the named underlayment, the named fastener, the stated exposure — as written scope, and to pay for it.
The product has a current evaluation report that addresses the code edition your jurisdiction has actually adopted, and a separate impact listing if impact matters where you live.

Think twice if

You are buying it for the fifty-year number. Nobody has watched one of these roofs reach year fifty, because the products have not existed that long.
The evaluation report gives the covering a Class C fire classification and your building is in a designated wildfire hazard area or near a lot line. Class C is not a preference in those places.
Nobody within a reasonable distance has installed the product before. A moulded unit with a proprietary interlock is not a thing a crew improvises, and the tested uplift value depends on the fastener the report names.
The proposal does not identify the product by name, or does not include the evaluation report number. You cannot check a claim about a product you cannot identify.
The roof will need repair matching in fifteen years and the profile or colour is one the manufacturer has already replaced once. Moulded products change; the roof stays.
Your ownership horizon is short. You will pay the premium for a covering whose advantage — if it materialises — arrives after you have sold the house, and warranty transferability is a clause you will have to read for yourself.

What changes the answer

Which jurisdiction you are in. A report written against the model IBC and IRC does not by itself address California, Los Angeles, or Florida; those take separate supplements or a separate state approval, each with its own conditions.
Whether the fire class you need is achievable with an underlayment you are willing to specify. In one report read for this page, the same tile is Class A with either of two named proprietary underlayments and Class C with ordinary No. 30 felt.
Whether impact resistance was evaluated at all. In one of the three reports it simply is not among the properties evaluated; in another it is a separate UL classification you look up separately.
How your framing loads change. Composite is light against stone, and not light against nothing. What matters is the weight going on relative to what is coming off.
The age of the house. Pre-1990 roofing felts, mastics and shingles may contain asbestos, and every one of these reports requires a full tear-off, which is exactly the operation that disturbs them.
Whether the manufacturer is likely to exist in year forty. That is not a rhetorical question, and the section on warranty arithmetic below explains what the answer is worth.

The mechanism

Four kinds of evidence, and only one of them is a promiseSection link

This diagram is the argument of the page. Every bar on it is a different kind of knowledge about the same roof, drawn to the same scale.

The evidence horizon for a composite roof covering. The twelve-year and fifty-year figures are placeholders, in the same way an arithmetic example uses round numbers; the text below explains how to replace them with the two numbers that apply to the product in front of you. The full description is available to screen readers and repeated in the prose.Original diagram, Understanding Roofing.

A roofing decision is normally made by comparing service lives. That works for materials with a long observed record — you can argue about whether a slate roof lasts eighty years or a hundred and twenty, because slate roofs of both ages exist and can be looked at. For a moulded polymer covering, the comparison quietly breaks, and it breaks in a way that is easy to miss because the number on the brochure is bigger than slate’s warranty and smaller than slate’s life.

The diagram separates four things that are usually said in the same breath.

1. Accelerated laboratory weathering

The acceptance criterion these products are evaluated against requires accelerated exposure. One report read for this page records that the tiles were tested for tensile properties to ASTM D638 and flexural properties to ASTM D790 “both as manufactured and Xenon Arc weathered,” along with temperature cycling. Another records data “showing no loss of tensile strength after aging to ASTM G155.”

That is real evidence, and it is worth having. It is not evidence about years. NIST, which runs the United States’ research programme on exactly this problem, states the difficulty directly: “the development of service life prediction tools from accelerated weathering is difficult due to the myriad of differences between outdoor and indoor exposure conditions, such as ultraviolet (UV) spectrum, UV intensity, and moisture/temperature variability.” The fact that a national metrology institute has a standing programme to build that correlation is the clearest possible signal that the correlation is not yet a settled thing you can read off a chamber.

2. Independently measured outdoor weathering

There is one place where a roof product’s real outdoor change is measured by a third party and published: the Cool Roof Rating Council’s directory, which lists initial and three-year-aged solar reflectance, thermal emittance and Solar Reflectance Index. The aged values come from natural weathering at approved test farms in Arizona, Ohio and Florida — hot-dry, cold-temperate and hot-humid. Products can display interim laboratory-aged “Rapid Ratings” until the three-year exposure finishes, at which point the real three-year values replace them.

Three years. That is the longest independently measured outdoor exposure publicly available for a roof covering, and it is measuring optical properties rather than whether the unit is still holding water. It is a genuinely useful data point and it is nowhere near the length of a warranty.

3. The field record

The green bar is the one that matters most and is discussed least: how long roofs of this exact formulation have existed anywhere. You can bound it without asking the manufacturer, because evaluation reports carry dates. One report read for this page was issued in August 2014 and revised in August 2021. Another was published in November 2022 and revised in December 2025. A third was issued in November 2025 and is subject to renewal in November 2026.

The first-issue date of a product’s report is not the date the product first shipped, and it is not a service-life figure. It is a floor on the question “how long has anyone been able to check this?” — and a floor is more than most brochures give you.

The awkward part is the annotation at the top right of the diagram. A manufacturer can change the polymer blend, the filler, the stabiliser package, or the profile, and keep the product name. The report is reissued; the family grows; the field record for the new formulation starts at zero. One report read for this page shows that happening under a single unchanged report number: its March 2024 edition covered four products, and its December 2025 edition covers six, listing supporting test evidence separately for three of them. That is normal product development. It is also the reason a brand’s longevity is not the same as a formulation’s.

4. The warranty term

The top bar is the only one that is not a measurement of anything. It is a contractual promise about future conduct, written by the party that would have to honour it, and — as the wedge in the diagram shows — most long roofing warranties do not promise the same thing in year forty that they promise in year two. The section on warranty arithmetic below works that through with numbers.

None of this makes composite roofing a bad choice. It makes the usual reason for choosing it — the biggest number on the page — the weakest evidence on the page. Everything else in the shaded region of that diagram is a projection, and a projection is not improved by being printed in a larger font.

Definitions

What is actually under the wordSection link

Three products, three chemistries, three different sections of the specification system architects write from. The word on the brochure is the only thing they share.

There is no legal or technical definition of “composite” as a roof covering. There is, however, a place where the industry is forced to be precise: the CSI MasterFormat sections that evaluation reports and architects’ specifications file products under. Those sections do not say composite. They say plastic and they say rubber.

07 32 26 — Plastic Roof Tiles. Where one report files a product it describes as “polymer-based roof tiles designed to provide the look of natural shake or slate,” manufactured “with a proprietary formulation of polymers and other additives.”
07 31 53 — Plastic Shakes. Where another files “synthetic composite roofing tiles manufactured using virgin and recycled polyolefin polymers.”
07 31 33 — Composite Rubber Shingles. Where a third files coverings “molded from a proprietary formulation including post-consumer waste recycled rubber and additives.”

Polyolefin, an unnamed polymer blend, and recycled tyre rubber are not variations on a theme. They age differently, they burn differently, they move differently with temperature, and they are made by companies of very different sizes and ages. A homeowner who has read a good review of one has learned nothing whatsoever about the other two.

Notice the other word that appears in all three descriptions: proprietary. The formulation is not disclosed. That is normal and lawful, and it means the only route to knowing anything about how the material behaves is the test data in the evaluation report — the thing this page keeps pointing at.

The near-homonym that costs people money

In American roofing usage, “composition shingle” — usually shortened to “comp” — has long meant an ordinary asphalt shingle, because an asphalt shingle is a composite of mat, asphalt and granules. “Composite shingle” increasingly means the moulded synthetic products on this page, at several times the price. The two words are one letter apart and describe products at opposite ends of the cost range.

The fix is not vocabulary. It is insisting that any proposal names a manufacturer and a product. A line item reading “composite shake” is not something you can price, check, or compare, and it is the first thing to send back.

Where composite sits relative to the code’s own list

The 2024 International Residential Code — model text, a document a state or local government may adopt, amend, or ignore, and not the law where you live until it does — gives prescriptive requirements, section by section, for asphalt shingles, clay and concrete tile, metal roof shingles, mineral-surfaced roll roofing, slate, wood shingles, wood shakes, built-up roofs, metal roof panels, modified bitumen, thermoset and thermoplastic single-ply, sprayed polyurethane foam, and building-integrated photovoltaics. There is no section for polymer composites.

The near miss is instructive. The chapter’s own covering list names “slate and slate-type shingles” and sends them to section R905.6, which sounds as though it might reach an imitation — until R905.6.4, which requires that slate shingles “comply with ASTM C406.” ASTM C406 is a specification for quarried stone. A moulded polymer cannot meet it, so the section that appears to name the product cannot actually admit it. Composite roofing therefore reaches a roof by the alternative-materials route, which is the subject of the next section, and which is why these products come with evaluation reports rather than with a code section number.

The reference

What three real composite products' evaluation documents actually saySection link

All three of these reports are published in full and free to read. Everything below is quoted or summarised from them, and every row is a question worth asking about whatever product is in front of you.

Three composite roof coverings as described by their own public evaluation documents, read on 14 August 2026. This is a comparison of documents, not of products: nothing here is a performance comparison, a recommendation, or a survey of the category.
What the document records	Brava One Cedar Shake / Slate — ICC-ES ESR-4756	EcoStar Empire series — UL ER18920-01	Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013
What the report says it is	“Polymer-based roof tiles designed to provide the look of natural shake or slate,” manufactured “with a proprietary formulation of polymers and other additives.”	“Synthetic composite roofing tiles manufactured using virgin and recycled polyolefin polymers.”	“Composite roof coverings and accessories molded from a proprietary formulation including post-consumer waste recycled rubber and additives.”
Specification section it files under	07 32 26 — Plastic Roof Tiles	07 31 53 — Plastic Shakes, and 07 32 26 — Plastic Roof Tiles	07 31 33 — Composite Rubber Shingles
Criterion it was evaluated against	ICC-ES AC07, Acceptance Criteria for Special Roofing Systems, dated February 2014 (editorially revised January 2021).	ICC-ES AC07, plus AC10 for quality documentation. Tensile (ASTM D638) and flexural (ASTM D790) properties tested “both as manufactured and Xenon Arc weathered,” plus temperature cycling.	ICC-ES AC07, with data “showing no loss of tensile strength after aging to ASTM G155,” plus ASTM D635 burning rate (CC2) and ASTM D1929 spontaneous ignition temperature above 650 °F.
Fire classification, and what the assembly requires	Class A or Class C, depending entirely on underlayment. Class A: one layer of either of two specifically named proprietary underlayments, each with its own evaluation report, over minimum 15/32-inch plywood at 4:12 and 10-inch exposure. Class C: one layer of ASTM D226 Type II No. 30 felt.	Tested Class A and Class C to ANSI/UL 790 (ASTM E108); the qualifying assemblies, including barrier board and underlayment options, are set out in the report’s own table.	Class C only. The report’s approved use is “roofing coverings for use in Class C roof assemblies.”
Impact resistance	Not among the properties evaluated. The report evaluates weather resistance, fire classification and wind resistance.	Not evaluated in the report itself. It points to separate UL classification reports under UL 2218 and to the UL certification directory categories.	“Class IV impact resistance rated evaluated following UL 2218,” with installation per the report’s own table.
Wind	196 psf allowable uplift with two No. 8 by 2-inch screws per tile, being the tested ultimate pressure divided by a safety factor of 2. With ring-shank nails instead: Exposure B only, maximum 130 mph design wind speed, roof height 40 ft or less. Allowable design uplift “must be determined… by a registered design professional.”	Uplift tested to ANSI/UL 580 and ANSI/UL 1897, with a safety factor of 2.0. The report states the allowable pressure “is for the roof system only” and that deck and framing must be designed separately for component and cladding wind loads. Only the manufacturer’s specified fasteners are permitted.	Wind resistance is among the properties evaluated; the report’s installation tables govern.
Installed weight	304 lb per 100 sq ft (cedar shake) and 310 lb per 100 sq ft (slate) at 10-inch exposure.	Not stated in this report.	2.1 to 3.4 lb per sq ft depending on product and exposure — roughly 210 to 340 lb per roofing square.
Minimum slope	4:12.	3:12 minimum, exposure-dependent — for example 3:12 at 7-inch exposure and 6:12 at 8-inch exposure for one profile. Slopes below 3:12 are “not recommended.”	4:12 to 20:12.
Re-roofing	“The existing roof covering and underlayment must be completely removed.”	“Existing roof covering materials are to be removed prior to installation.”	Intended for use over existing construction only “where existing roof coverings and underlayment have been removed.”
Code editions the report addresses	2021 and 2018 IBC and IRC, with separate supplements for the 2023 Los Angeles codes, the 2022 California codes (including the Wildland-Urban Interface pathway) and Florida.	2012, 2009 and 2006 IBC and IRC.	2021, 2018 and 2015 IBC and IRC, plus the 2023 and 2020 Florida Building Code, Building and Residential.
Dates on the document	Issued November 2025; subject to renewal November 2026.	Issued 15 August 2014; revised 5 August 2021. Directs readers to UL’s Product iQ database for current status.	Published November 2022; revised December 2025; expires March 2027. Its March 2024 edition, under the same report number, covered four products and listed the 2024 code editions on its cover; this one covers six and does not.
What the issuing body says about itself	Reports “are not to be construed as… an endorsement of the subject of the report or a recommendation for its use,” and there is “no warranty by ICC Evaluation Service, LLC… as to any finding or other matter in this report.”	“The approval of building products, materials or systems is under the responsibility of the applicable authorities having jurisdiction,” and reports “shall not be used in any manner that implies an endorsement.”	Use outside the described applications “requires approval by the authority having jurisdiction.”

Read this table one item at a time

What the report says it is

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: “Polymer-based roof tiles designed to provide the look of natural shake or slate,” manufactured “with a proprietary formulation of polymers and other additives.”
EcoStar Empire series — UL ER18920-01: “Synthetic composite roofing tiles manufactured using virgin and recycled polyolefin polymers.”
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: “Composite roof coverings and accessories molded from a proprietary formulation including post-consumer waste recycled rubber and additives.”

Specification section it files under

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: 07 32 26 — Plastic Roof Tiles
EcoStar Empire series — UL ER18920-01: 07 31 53 — Plastic Shakes, and 07 32 26 — Plastic Roof Tiles
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: 07 31 33 — Composite Rubber Shingles

Criterion it was evaluated against

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: ICC-ES AC07, Acceptance Criteria for Special Roofing Systems, dated February 2014 (editorially revised January 2021).
EcoStar Empire series — UL ER18920-01: ICC-ES AC07, plus AC10 for quality documentation. Tensile (ASTM D638) and flexural (ASTM D790) properties tested “both as manufactured and Xenon Arc weathered,” plus temperature cycling.
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: ICC-ES AC07, with data “showing no loss of tensile strength after aging to ASTM G155,” plus ASTM D635 burning rate (CC2) and ASTM D1929 spontaneous ignition temperature above 650 °F.

Fire classification, and what the assembly requires

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: Class A or Class C, depending entirely on underlayment. Class A: one layer of either of two specifically named proprietary underlayments, each with its own evaluation report, over minimum 15/32-inch plywood at 4:12 and 10-inch exposure. Class C: one layer of ASTM D226 Type II No. 30 felt.
EcoStar Empire series — UL ER18920-01: Tested Class A and Class C to ANSI/UL 790 (ASTM E108); the qualifying assemblies, including barrier board and underlayment options, are set out in the report’s own table.
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: Class C only. The report’s approved use is “roofing coverings for use in Class C roof assemblies.”

Impact resistance

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: Not among the properties evaluated. The report evaluates weather resistance, fire classification and wind resistance.
EcoStar Empire series — UL ER18920-01: Not evaluated in the report itself. It points to separate UL classification reports under UL 2218 and to the UL certification directory categories.
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: “Class IV impact resistance rated evaluated following UL 2218,” with installation per the report’s own table.

Wind

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: 196 psf allowable uplift with two No. 8 by 2-inch screws per tile, being the tested ultimate pressure divided by a safety factor of 2. With ring-shank nails instead: Exposure B only, maximum 130 mph design wind speed, roof height 40 ft or less. Allowable design uplift “must be determined… by a registered design professional.”
EcoStar Empire series — UL ER18920-01: Uplift tested to ANSI/UL 580 and ANSI/UL 1897, with a safety factor of 2.0. The report states the allowable pressure “is for the roof system only” and that deck and framing must be designed separately for component and cladding wind loads. Only the manufacturer’s specified fasteners are permitted.
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: Wind resistance is among the properties evaluated; the report’s installation tables govern.

Installed weight

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: 304 lb per 100 sq ft (cedar shake) and 310 lb per 100 sq ft (slate) at 10-inch exposure.
EcoStar Empire series — UL ER18920-01: Not stated in this report.
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: 2.1 to 3.4 lb per sq ft depending on product and exposure — roughly 210 to 340 lb per roofing square.

Minimum slope

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: 4:12.
EcoStar Empire series — UL ER18920-01: 3:12 minimum, exposure-dependent — for example 3:12 at 7-inch exposure and 6:12 at 8-inch exposure for one profile. Slopes below 3:12 are “not recommended.”
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: 4:12 to 20:12.

Re-roofing

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: “The existing roof covering and underlayment must be completely removed.”
EcoStar Empire series — UL ER18920-01: “Existing roof covering materials are to be removed prior to installation.”
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: Intended for use over existing construction only “where existing roof coverings and underlayment have been removed.”

Code editions the report addresses

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: 2021 and 2018 IBC and IRC, with separate supplements for the 2023 Los Angeles codes, the 2022 California codes (including the Wildland-Urban Interface pathway) and Florida.
EcoStar Empire series — UL ER18920-01: 2012, 2009 and 2006 IBC and IRC.
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: 2021, 2018 and 2015 IBC and IRC, plus the 2023 and 2020 Florida Building Code, Building and Residential.

Dates on the document

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: Issued November 2025; subject to renewal November 2026.
EcoStar Empire series — UL ER18920-01: Issued 15 August 2014; revised 5 August 2021. Directs readers to UL’s Product iQ database for current status.
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: Published November 2022; revised December 2025; expires March 2027. Its March 2024 edition, under the same report number, covered four products and listed the 2024 code editions on its cover; this one covers six and does not.

What the issuing body says about itself

Brava One Cedar Shake / Slate — ICC-ES ESR-4756: Reports “are not to be construed as… an endorsement of the subject of the report or a recommendation for its use,” and there is “no warranty by ICC Evaluation Service, LLC… as to any finding or other matter in this report.”
EcoStar Empire series — UL ER18920-01: “The approval of building products, materials or systems is under the responsibility of the applicable authorities having jurisdiction,” and reports “shall not be used in any manner that implies an endorsement.”
Euroshield Ranchland / Rundle / Beaumont / Vermont — QAI CERus-1013: Use outside the described applications “requires approval by the authority having jurisdiction.”

These three products were chosen because their documents are public and complete, not because they are representative, best, or worst. Every cell is a statement about a document on the date it was read; documents are revised and expire. Read the current document for the product you are actually being offered.

Read down the fire row and the impact row again. On the same page, one product is Class A only with a named proprietary underlayment; one is Class C and nothing else; one has no impact evaluation at all while another carries Class IV. If you had walked into three showrooms and heard “composite, Class A, Class 4, fifty-year warranty” in all three, you would have heard one sentence and been sold three genuinely different things.

That is the practical case for the worksheet in the next section. Every one of those differences is free to check, and none of them requires you to know anything about polymer chemistry.

The worksheet

Ten claims you will hear, and the document that settles each oneSection link

Print this, or keep it open during the sales conversation. The third column is free and public in every case; the fourth is the part nobody volunteers.

A verification worksheet for composite roofing claims: what substantiates each claim, where to look it up, and what it still does not tell you.
The claim	What would substantiate it	Where to look it up	What it still does not tell you
1 · “It's Class A fire rated.”	The fire table in the product’s evaluation report, naming the deck, underlayment, slope and exposure that produce the class.	The issuing body’s public report directory — ICC-ES, UL’s Product iQ, or the evaluating laboratory’s site.	Whether the assembly being installed on your roof is the row that was tested. Change the underlayment and the class changes with it.
2 · “It's Class 4 impact rated.”	A UL 2218 classification. It is often a separate listing from the evaluation report, and sometimes it does not exist at all.	The UL certification directory, or the impact section of the evaluation report if it has one.	How the product resists impact after fifteen years of ultraviolet exposure. UL 2218’s own scope excludes weathering, temperature and aging.
3 · “It's rated for high winds.”	The uplift table in the evaluation report: allowable pressure in psf, the safety factor applied, and the exact fastener the value belongs to.	The evaluation report.	The design pressure at your building’s corners and edges. That is engineering under the wind provisions of the adopted code, done by a registered design professional for this building.
4 · “It's code approved.”	The scope page of the evaluation report, which lists the code editions it addresses.	The report’s cover page.	Whether your jurisdiction adopted that edition, and whether your building official accepts the report. Acceptance of an alternative material is typically granted project by project.
5 · “It's approved in Florida.”	A Florida product approval (an FL number) or a Miami-Dade Notice of Acceptance, or a Florida supplement to the evaluation report.	The Florida Building Code Online product approval search, by FL number or manufacturer; Miami-Dade runs its own separate system.	Anything outside that jurisdiction. A Florida approval says nothing about Colorado, and Miami-Dade carries requirements the rest of Florida does not.
6 · “It's been tested for decades of weathering.”	The evidence section of the report: accelerated exposure to ASTM G155 with tensile and flexural retention, plus temperature cycling.	The evaluation report’s supporting evidence section.	Years. NIST describes converting accelerated exposure into a service-life prediction as difficult and an open research problem, not a solved conversion.
7 · “It carries a 50-year warranty.”	The complete warranty document — in particular the proration clause, the transfer clause, and the exclusions.	The manufacturer, on request, before you buy. Federal rules require a written warranty on a consumer product to disclose its duration, coverage, exclusions and claim procedure in a single document.	Whether the company will exist in year forty. If it does not, the promise becomes a general unsecured claim.
8 · “It's made from recycled material.”	The product description in the report, which states the material, plus a qualified recycled-content claim.	The evaluation report; the FTC Green Guides set out how the claim itself should be qualified.	Anything about durability. Recycled content is a sourcing statement. It is not evidence of performance in either direction.
9 · “It's energy efficient.”	A Cool Roof Rating Council listing with solar reflectance, thermal emittance and SRI.	The CRRC rated products directory.	Whether the figure quoted is the initial value, an interim laboratory-aged Rapid Rating, or a real three-year aged value — and whether a cool roof helps or costs you in your climate.
10 · “It's much lighter than slate.”	The installed weight in the report, in pounds per square foot or per 100 square feet.	The evaluation report.	Whether your framing carries it. The number that matters is the difference between what comes off and what goes on, and if that difference is upward it is a question for an engineer.

Read this table one item at a time

1 · “It's Class A fire rated.”

What would substantiate it: The fire table in the product’s evaluation report, naming the deck, underlayment, slope and exposure that produce the class.
Where to look it up: The issuing body’s public report directory — ICC-ES, UL’s Product iQ, or the evaluating laboratory’s site.
What it still does not tell you: Whether the assembly being installed on your roof is the row that was tested. Change the underlayment and the class changes with it.

2 · “It's Class 4 impact rated.”

What would substantiate it: A UL 2218 classification. It is often a separate listing from the evaluation report, and sometimes it does not exist at all.
Where to look it up: The UL certification directory, or the impact section of the evaluation report if it has one.
What it still does not tell you: How the product resists impact after fifteen years of ultraviolet exposure. UL 2218’s own scope excludes weathering, temperature and aging.

3 · “It's rated for high winds.”

What would substantiate it: The uplift table in the evaluation report: allowable pressure in psf, the safety factor applied, and the exact fastener the value belongs to.
Where to look it up: The evaluation report.
What it still does not tell you: The design pressure at your building’s corners and edges. That is engineering under the wind provisions of the adopted code, done by a registered design professional for this building.

4 · “It's code approved.”

What would substantiate it: The scope page of the evaluation report, which lists the code editions it addresses.
Where to look it up: The report’s cover page.
What it still does not tell you: Whether your jurisdiction adopted that edition, and whether your building official accepts the report. Acceptance of an alternative material is typically granted project by project.

5 · “It's approved in Florida.”

What would substantiate it: A Florida product approval (an FL number) or a Miami-Dade Notice of Acceptance, or a Florida supplement to the evaluation report.
Where to look it up: The Florida Building Code Online product approval search, by FL number or manufacturer; Miami-Dade runs its own separate system.
What it still does not tell you: Anything outside that jurisdiction. A Florida approval says nothing about Colorado, and Miami-Dade carries requirements the rest of Florida does not.

6 · “It's been tested for decades of weathering.”

What would substantiate it: The evidence section of the report: accelerated exposure to ASTM G155 with tensile and flexural retention, plus temperature cycling.
Where to look it up: The evaluation report’s supporting evidence section.
What it still does not tell you: Years. NIST describes converting accelerated exposure into a service-life prediction as difficult and an open research problem, not a solved conversion.

7 · “It carries a 50-year warranty.”

What would substantiate it: The complete warranty document — in particular the proration clause, the transfer clause, and the exclusions.
Where to look it up: The manufacturer, on request, before you buy. Federal rules require a written warranty on a consumer product to disclose its duration, coverage, exclusions and claim procedure in a single document.
What it still does not tell you: Whether the company will exist in year forty. If it does not, the promise becomes a general unsecured claim.

8 · “It's made from recycled material.”

What would substantiate it: The product description in the report, which states the material, plus a qualified recycled-content claim.
Where to look it up: The evaluation report; the FTC Green Guides set out how the claim itself should be qualified.
What it still does not tell you: Anything about durability. Recycled content is a sourcing statement. It is not evidence of performance in either direction.

9 · “It's energy efficient.”

What would substantiate it: A Cool Roof Rating Council listing with solar reflectance, thermal emittance and SRI.
Where to look it up: The CRRC rated products directory.
What it still does not tell you: Whether the figure quoted is the initial value, an interim laboratory-aged Rapid Rating, or a real three-year aged value — and whether a cool roof helps or costs you in your climate.

10 · “It's much lighter than slate.”

What would substantiate it: The installed weight in the report, in pounds per square foot or per 100 square feet.
Where to look it up: The evaluation report.
What it still does not tell you: Whether your framing carries it. The number that matters is the difference between what comes off and what goes on, and if that difference is upward it is a question for an engineer.

Every document in the third column is free. None of them requires a login, a site visit, or a roof. If a salesperson cannot produce the product name and report number that makes this worksheet usable, that is itself the answer to the first question on it.

The number on the brochure

What a 50-year warranty pays in year 30Section link

This is the arithmetic behind the tapering wedge in the diagram. Do it with your own document's numbers before the warranty term influences the decision.

Long roofing warranties are typically limited and prorated: full coverage for an initial period, then a declining share of the original material price for the remainder. The structure below is an arithmetic illustration, in the same way a worked example uses round numbers. Your terms are whatever your document says — and federal rules require a written warranty on a consumer product to disclose the duration, what is covered, what the warrantor will do, and the claim procedure, in one document you can read before buying.

The illustrative terms

Term: 50 years, limited.
Covers: replacement material only. Labour, tear-off, disposal, underlayment, flashing and accessories excluded.
Non-prorated period: years 1 through 10.
Proration: straight-line from 100% at the end of year 10 to 0% at year 50 — that is, over 40 years.

The formula

remaining coverage = 1 − (years elapsed − 10) ÷ 40, for years 10 through 50

Worked through

Take the covering-material line from your own proposal and call it M. For the arithmetic below, use M = $10,000 as a placeholder and substitute your real figure.

Year 8. Inside the non-prorated period. coverage = 100% → $10,000 of material.
Year 20. 1 − (20 − 10) ÷ 40 = 0.75 → $7,500.
Year 30. 1 − (30 − 10) ÷ 40 = 0.50 → $5,000.
Year 45. 1 − (45 − 10) ÷ 40 = 0.125 → $1,250.

Three things that shrink those numbers further

It is measured against the original price, not tomorrow’s. The year-30 figure of $5,000 is half of what the material cost in year zero. It is not half of what replacing it costs in year thirty. Every year of material-price increase widens that gap, and the warranty does not index.
Material is not the job. The excluded items — labour, tear-off, disposal, underlayment, flashing, accessories — are a large share of what a re-roof costs, and on a product whose fire classification depends on a named underlayment, the excluded underlayment is not optional. Whatever fraction of your original proposal M represented, the year-30 payout is half of that fraction.
There is a floor below which nobody claims. Somewhere on that declining line, the payout stops being worth the documentation, the inspection, the correspondence and the delay. Find that year. It is the real end of the warranty, and it arrives well before year fifty.

And one thing that can zero them

All of the above assumes the warrantor exists. If it does not, the promise becomes a general unsecured claim. The Bankruptcy Code’s distribution rules put claims in six classes, and “each class must be paid in full before the next lower class is paid anything” — with general unsecured claims behind secured creditors, priority claims and administrative expenses. Most individual Chapter 7 cases distribute nothing to unsecured creditors at all.

Why this bears on composite specifically

Every steep-slope category sells warranties. Composite is the one where the warranty term routinely exceeds the entire observed history of the product class, which means the warranty is doing more persuasive work here than anywhere else on the roof. When the evidence is thin, the promise gets bigger. That is not a scandal; it is what a young category has to offer. It is a reason to weigh the promise at its arithmetic value rather than at its headline.

History is not an accusation, but it is on the record

The generation of moulded imitation shakes before this one was made of cement and wood fibre rather than polymer. One of those manufacturers, American Cemwood Corporation, settled a class action in 1999 over claims that its cement-fibre roofing products had failed; the parent company that had acquired it later recorded a $25 million pre-tax benefit in 2003 from a settlement with Cemwood’s insurers, which is how the episode reaches the public record at all. Those are the facts a filing supports, and they are all this page asserts: the class size, the settlement totals and the failure mechanism circulate widely online but not in any government or court source this page could locate, so they are not repeated here.

That was a different material with a different chemistry, and nothing about it predicts anything about the polymer products sold today. It is here for one reason: a long warranty on a young moulded-shake category is a promise about a future, and futures are where those promises get tested.

Scope

Every one of these reports requires a full tear-offSection link

This is the least glamorous finding on the page and one of the most consequential for the price, the schedule, and — on an older house — the safety of the work.

There is no recover option in any of the three documents. One states that “the existing roof covering and underlayment must be completely removed.” Another that “existing roof covering materials are to be removed prior to installation.” The third contemplates use over existing construction only “where existing roof coverings and underlayment have been removed.”

Three consequences follow.

A proposal offering to lay composite over the old roof is outside the conditions of use. That is not a technicality: the conditions of use are what the fire classification and the uplift figures were established under, and a code official accepting the product as an alternative material is accepting it on those terms.
The deck gets exposed, which is when surprises arrive. Rot concentrates where water has been getting in, which is at the flashings and the penetrations. That belongs in the contract as a written allowance with a unit rate before the first shingle comes off — see flashing for where to expect it.
On a house built before about 1990, tear-off is exactly the operation that disturbs old felts, mastics and shingles.

The scheduling consequence is worth stating plainly too. A full tear-off means the building is open, which means weather windows matter, which means a moulded product with a longer install time than asphalt is exposed to more of them. Ask how many squares a day the crew expects, and what happens to the open deck overnight.

Money

What composite costs — and why this page does not publish a numberSection link

A national dollar figure for “composite roofing” would be an average across three unrelated chemistries, a thin and uneven installer market, and products that differ by a factor of several in weight and specification. Here is what actually decides the number.

Composite is a premium covering. That much is not in dispute and does not need a citation. What cannot be honestly stated at national scale is a range, because the things that move the price are almost all local or product-specific:

Which product. A rubber panel and a moulded polymer slate are different products in different price brackets. There is no single figure that describes both.
The assembly the fire class requires. Where Class A depends on a named proprietary underlayment rather than felt, that underlayment is a real line item and it is not optional if you want the class.
The fastener. One report’s higher uplift value belongs to screws rather than nails. Two screws per unit across a whole roof is labour, and it is the labour that buys the tested number.
How many crews within reach have installed it. This is the biggest single variable in most markets and the one nobody quotes. A product with two experienced crews in a metro area is priced differently from one with twenty.
Full tear-off, always. No recover option, plus disposal, plus a deck allowance that should be written before work starts.
Complexity. Moulded units with interlocks and defined exposures are less forgiving around valleys, dormers, hips and penetrations than a shingle you can cut freely.
Whether the plane below the minimum slope has been priced. A porch or addition below 3:12 or 4:12 needs a different covering, and it is frequently missing from a first proposal.

The lifecycle argument — that a higher price buys fewer replacements — is the argument composite is sold on, and it is the one this page cannot verify, because the denominator is the service life and the service life has not been observed. What you can do instead is run the comparison with an explicit assumption you choose and can defend, and see how sensitive the answer is to it. If the case only works when you assume the full warranty term, the case rests on the warranty term.

For how this site builds and states any cost figure — units, scope, geography, as-of date, and confidence — see the cost methodology. For where a covering choice sits inside a whole roof price, start at the roof cost hub. To make competing proposals comparable before price enters the conversation, use the hiring and quotes path and the checklist in the roof buying kit.

Considerations

What changes this on a real buildingSection link

Code and jurisdiction

There is no nationwide building code for site-built houses in the United States. The model codes contain a provision — its section number has moved between editions, appearing as R104.11 in the 2015, 2018 and 2021 International Residential Code and as section 104.2.3 in the 2024-cycle International Building Code text — that lets a building official accept a material the code does not prescribe. The NRCA’s Mark Graham summarises the test the official applies: the alternative must be found “not less than the equivalent prescribed in the code in quality, strength, durability, effectiveness, fire resistance and safety.”

Two consequences follow, and both are routinely glossed over in sales conversations. First, an evaluation report states which code editions it addresses, and that list can be old: one report read for this page addresses the 2012, 2009 and 2006 IBC and IRC and nothing later. Second, acceptance of an alternative is something the code official grants, and Graham notes that such acceptances “typically apply only to the specific project for which they were granted.” A report is evidence you bring to the permit office. It is not, by itself, permission.

Record the jurisdiction, the adopted code edition, its amendments and its effective date, and confirm with the authority having jurisdiction before treating any report on any product as settling the question. A report written against the model IBC and IRC does not address California, Los Angeles or Florida until it carries the supplement for that jurisdiction.

Fire

This is where the assembly rule stops being an abstraction. The model text of the 2024 IRC states that where Class A, B or C roof assemblies are required, they “shall be tested in accordance with ASTM E108 or UL 790” — the classification belongs to the assembly, not to the covering sitting on a pallet. Which edition your jurisdiction has adopted, and with what amendments, is a separate question with a local answer.

One report read for this page shows exactly what that means in practice. The same polymer tile, on the same minimum 15/32-inch plywood deck, at the same 4:12 slope and 10-inch exposure, is listed as a Class A roof covering with one layer of either of two specifically named proprietary underlayments, each carrying its own evaluation report — and as a Class C roof covering with one layer of ordinary ASTM D226 Type II No. 30 asphalt-saturated organic felt. Same tile. Different underlayment. Different class.

A different product, from a different manufacturer, is approved in its report only for “use in Class C roof assemblies.” No underlayment substitution changes that.

Where wildfire exposure is the concern, the jurisdiction takes over. The California supplement to one of these reports records that when installed as a Class A roof covering under the relevant California Building Code and Residential Code sections, the products were evaluated for use in any Fire Hazard Severity Zone within a State Responsibility Area or any Wildland-Urban Interface Fire Area. That is a jurisdiction-specific evaluation, not a property of the tile.

A fire classification is a property of a tested assembly — deck, underlayment and covering together under a defined test — and never of the covering alone. Ask which system number in the report is being installed on your roof, and require the underlayment named in that row by product name, not by description.

Hail and impact

Impact resistance is a separate question from everything else in the report, and it is easy to assume it has been answered when it has not. Of the three products read for this page, one records a Class IV impact classification evaluated to UL 2218; one references UL 2218 classification as a separate UL listing to be looked up in the certification directory; and one does not list impact resistance among the properties evaluated at all — its report covers weather resistance, fire classification and wind resistance, and stops there.

Even where a Class 4 exists, read what the test is. UL 2218 in its own scope states that “this test method does not evaluate the effect of weathering, temperature, aging or similar effects on the impact resistance of prepared roof covering materials.” The Insurance Institute for Business & Home Safety makes the same point about the whole family of standards: they “evaluate new products and do not account for the effects of weathering, temperature, aging, or similar factors.” For a polymer that is expected to change under ultraviolet exposure — which is precisely why the acceptance criterion demands accelerated weathering — the gap between “Class 4 when new” and “Class 4 at twenty years” is not a small one, and nobody has published a number for it.

“Class 4 impact resistant” does not mean hail proof. IBHS notes that the UL 2218 criterion is whether a crack is visible on the back of the specimen after two impacts in the same place, while its own test evaluates deformation, granule loss and breaches — the damage a homeowner and an adjuster actually argue about. Ask for the listing, and never treat it as a promise about a storm.

Wind

The wind numbers in these reports are more specific, and more conditional, than a marketing figure. One report gives an allowable uplift pressure of 196 pounds per square foot when the tile is fixed with two No. 8 by two-inch corrosion-resistant wood screws — with the allowable figure being the tested ultimate pressure divided by a safety factor of 2 — and separately limits the same tile, when fixed with ring-shank nails, to Exposure B locations with a maximum design wind speed of 130 mph and a roof height of 40 feet or less. The report is explicit that the allowable design uplift pressures “must be determined... by a registered design professional.”

Another report is equally explicit about the boundary of what it covers: “the allowable wind uplift pressure is for the roof system only. The deck and framing to which the roofing system is attached shall be designed for the applicable component and cladding wind loads in accordance with the applicable code.” And it permits only the fasteners the manufacturer specifies. Substituting a fastener does not reduce the tested value — it means there is no tested value for what was built.

Wind performance is site- and building-specific. Basic wind speed, exposure category, building height and geometry, pressure zone, enclosure, risk category, attachment and the tested assembly all matter, and the pressures at a roof's corners and edges are not the pressures in its field. A single mph figure on a brochure is not a code determination for your building.

Structural weight

Weight is the honest advantage of this category, and it is stated as a number in every report worth reading. The two products whose weights this page verified come in at roughly 210 to 340 pounds per roofing square installed, depending on product and exposure. That is a fraction of quarried stone, which is why a building that cannot carry natural slate can often carry an imitation of it. The question is never the absolute number, though — it is the difference between what comes off and what goes on, and whether that difference is positive. If it is, and the margin is not obviously generous, that is a question for an engineer looking at this building rather than a table.

Climate

You can read the recognised degradation modes for this category straight off the acceptance criterion. Products are exposed to xenon-arc light and re-tested for tensile and flexural properties, and they are temperature-cycled. Those two tests exist because ultraviolet degradation and thermal movement are what the criterion’s authors expected to matter for moulded polymer on a roof.

That tells you where to point your questions in a specific climate: intense ultraviolet exposure at altitude or in the desert southwest, wide daily temperature swings, and the cold end of the range where polymers stiffen. It does not tell you how any particular product behaves after fifteen years in any particular place, because that measurement has not been published.

Every product in this category moves with temperature, and the allowance for that movement lives in the manufacturer's installation instructions — which each of these reports requires to be on the jobsite and to be followed. Ask what the expansion allowance is and what the maximum uninterrupted run is before it matters.

Maintenance

Two maintenance realities recur across the category. The first is that a moulded unit is not necessarily walkable, which changes what a gutter clean, a chimney sweep, a satellite installation or a solar array costs on this roof for the rest of its life. The second is that cleaning methods and treatments for moss and algae are frequently constrained by the warranty document, and pressure washing a polymer surface is not a neutral act. Both are questions for the specific product, and both are cheaper to ask before the roof goes on.

Access and site conditions

Nothing on this page requires you to be on a roof or in an attic. The product name and the evaluation report number are on the proposal, on the pallet label, or embossed on the unit itself — one report requires the report number, the manufacturer’s mark and the month and year of production to appear either on the pallet label or embossed on each tile. Photographs from an installer, the delivery ticket, and the free public directories answer nearly every question here from a chair.

Do not climb onto a roof or into an attic to check any of this. Ground-based, window-based, document-based, and installer-supplied evidence answers every question on this page.

Warranty and repair

The warranty is the longest bar on the diagram and the only one that is a promiseSection link

Composite roofing is sold on its warranty more than any other steep-slope category. That makes reading the document, rather than the headline number, the single highest-value hour in the whole decision.

You are entitled to read it before you buy: Federal warranty rules require a written warranty on a consumer product costing more than $15 to disclose, in a single document and in readily understood language, who the warranty runs to; a clear description of what is covered and what is excluded; what the warrantor will do about a defect, malfunction or failure; when the term starts and how long it runs; the step-by-step claims procedure with contact details; any informal dispute mechanism; and the sentence “This warranty gives you specific legal rights, and you may also have other rights which vary from State to State.” If a salesperson cannot hand you that document, you are not being asked to evaluate a warranty. You are being asked to trust a number.
Whether federal warranty law reaches your roof at all: It depends on how you bought it, and the rule is more specific than most summaries admit. The FTC’s interpretations state that structural components of a dwelling — the list expressly includes roofing — are not consumer products when they are sold as part of real estate covered by a written warranty, and that the same is true of materials integrated into a home a consumer contracts with a builder to construct. But materials bought separately for home improvement or repair, roofing among them explicitly, are consumer products. A re-roof on a house you already own sits on a different side of that line from a new house. This is a jurisdiction- and fact-specific matter and the paragraph above is not legal advice.
Prorated is not the same as covered: A fifty-year limited warranty rarely promises the same thing in year forty that it promises in year two. A common structure is a non-prorated period followed by a straight-line decline to zero, against the original material price and not against what a replacement costs when you claim. The worked example below does the arithmetic. Find the proration clause first; it decides what the headline number is worth more than any other sentence in the document.
Transferability: Many long roofing warranties reduce their term, their coverage, or both on transfer, and many limit the number of transfers or require notice within a fixed window after a sale. On a fifty-year promise, this clause is the difference between an asset you can sell and a promise that dies with your ownership. Read it before the roof goes on, not when the house goes on the market.
The warrantor has to still exist: A warranty is an unsecured promise. If the company that wrote it fails, the promise becomes a general unsecured claim. Under the Bankruptcy Code’s distribution rules there are six classes of claim, and “each class must be paid in full before the next lower class is paid anything” — with general unsecured claims sitting behind secured creditors, priority claims and administrative expenses, and most individual Chapter 7 cases producing no distribution to unsecured creditors at all. Nobody can tell you whether a manufacturer will exist in year forty. What you can do is stop treating a fifty-year term as fifty years of protection and start treating it as a fifty-year bet on a company.
What tends to void or exclude: Installation outside the manufacturer’s published instructions, substituted fasteners, substituted underlayment, unapproved cleaning methods, foot traffic damage, and repairs by others are common exclusions across the category — and the first three are the same substitutions that would invalidate the tested fire and uplift values anyway. None of that is universal. Every one of those clauses is written differently in every document, which is exactly why the document, not a summary of one including this one, is the thing to read.

Repairability

Repairability is where a young category’s risk concentrates, because a repair happens at a moment in the future and needs three things that may not be there.

A matching unit. Moulded products are revised. Profiles are added, colours are reformulated, and product lines grow — one report read for this page went from four covered products to six between its March 2024 and December 2025 editions. A replacement from year eighteen may not be the shape, thickness or colour of the units around it.
A colour that still matches. The reason the CRRC publishes both an initial and a three-year-aged reflectance value is that roof surfaces change optically outdoors. A new unit set into a fifteen-year-old field is a new unit, visibly.
Somebody who has done it. These are interlocking moulded units with named fasteners and specific exposures. That is a smaller pool of installers than asphalt, and it is the pool that decides whether a repair is a morning or a project.
The right underlayment underneath. Where the Class A classification depends on a named underlayment, a repair that opens the assembly has to reinstate that underlayment — not whatever is on the truck. A repair can quietly downgrade the classification of the area it touches.

A warranty is a contract between a reader and whoever wrote it. What it covers, what voids it, whether it transfers, and how it is enforced are set by that document and by the law where the reader lives. Read the actual warranty for the product and the installer in front of you — not a summary of one, including this one.

Ask before you sign

Questions to ask an installerSection link

None of these require you to know roofing. Every one is answerable in a sentence by someone who has read the documents for the product they are proposing, and evasively by someone who has not.

What is the product's exact name, and what is its evaluation report number?
Everything else on this list depends on the answer, and it is the one question with a right answer that fits in a text message. A proposal that says “composite shake” and nothing else is a proposal you cannot check.
Which code editions does that report address, and which edition has this jurisdiction adopted?
Reports state their scope on the cover. One read for this page addresses the 2012, 2009 and 2006 codes and nothing later. If those two answers do not overlap, the conversation with the permit office happens before the deposit, not after.
Is the report current, and when does it expire or come up for renewal?
These documents carry expiry and renewal dates, and their contents change under an unchanged number — one of the three read for this page is subject to renewal a year after issue, and another was reissued in December 2025 covering two more products, and a different list of code editions on its cover, than its March 2024 edition. Current status is free to check in the issuing body’s public directory.
Which fire classification are we getting, which system number in the report is it, and which underlayment does that row require by name?
This is the question that separates a Class A roof from a Class C roof on the same tile. If the answer is a description rather than a product name and a report number, the answer is not yet an answer.
Has this product been evaluated for impact resistance, and if so under which listing?
Impact is frequently a separate listing from the evaluation report, and in at least one case it is not evaluated at all. If your insurer offers a discount for an impact classification, the listing — not the brochure — is the document that substantiates it.
What fastener does the report specify, and are you using exactly that?
The tested uplift value belongs to the fastener as much as to the tile. One report permits only the manufacturer’s specified fasteners; another gives a materially different wind limitation for nails than for screws.
What is the minimum slope in the report, and does every plane on this roof meet it?
Minimum slopes in this category run 3:12 to 4:12 and are sometimes tied to exposure. A porch, dormer or addition below that slope is a different covering and a different line item, not an afterthought.
Can I have the warranty document — the whole thing — before I sign anything?
Ask for the proration clause, the transfer clause and the exclusions specifically. A refusal, a delay, or a summary in place of the document tells you what the document says.
How many roofs of this product have you installed, and can I see one that is at least five years old?
For a young category this is worth more than a reference for a new roof. A five-year-old installation is the oldest evidence most local markets can offer, and looking at one costs an afternoon.
Was this house built before 1990, and how are you handling the existing felts and mastics at tear-off?
Every report read for this page requires the existing covering and underlayment to be removed. On an older house that is exactly the operation that disturbs material that may contain asbestos. The right answer involves testing before disturbance, not reassurance.

Require these in writing

The manufacturer, the product name, the profile, the colour and the exposure — and the evaluation report number.
The fire classification being delivered, the system number in the report that produces it, and the underlayment named in that row, by manufacturer and product name.
The impact listing, if one is being relied on, by standard and class.
The fastener type, length, diameter and metal, matched to the report.
The stated minimum slope, and how any plane below it is being covered instead.
Full tear-off of the existing covering and underlayment, with a deck-repair allowance and a unit rate in writing.
The ice-barrier extent, if one is required where you live, and how it relates to the eave detail.
Flashing by location, with metal and thickness stated — the reports defer valley and flashing details to the code and to the manufacturer's instructions.
The complete manufacturer warranty document, and the installer's workmanship warranty, attached rather than referenced.
A commitment to photographs of the underlayment and fastening before the covering goes on, delivered to you.

What goes wrong

Misconceptions and failure modesSection link

Common misconceptions

Common belief
Composite is a material, like slate or clay.
What is actually true
It is a category name covering several unrelated chemistries. The three products examined for this page are, in their own documents, a “proprietary formulation of polymers and other additives,” tiles “manufactured using virgin and recycled polyolefin polymers,” and coverings “molded from a proprietary formulation including post-consumer waste recycled rubber and additives.” Those are three different materials in one aisle. Nothing you learn about one transfers to another.
Common belief
Composite shingles and composition shingles are the same thing.
What is actually true
They are usually not, and the near-identical words cause real confusion in quotes. In American roofing usage, “comp” or “composition” has long been shorthand for asphalt shingles, while “composite” increasingly means the moulded synthetic products described here — a completely different price, weight and chemistry. If a proposal uses either word without a manufacturer and a product name, that is the ambiguity to resolve before comparing prices.
Common belief
A fifty-year warranty means the roof lasts fifty years.
What is actually true
A warranty is a contract about what a company will do, written by that company, usually prorated, usually limited to material, and enforceable only for as long as the company exists. It is not a measurement, and for this category it is longer than the entire observed history of the products it covers. Treat it as one term of a purchase, not as a service-life estimate.
Common belief
It says Class A on the literature, so the roof will be Class A.
What is actually true
The classification belongs to the tested assembly. In one report read for this page, the same tile on the same deck at the same slope is Class A with either of two named proprietary underlayments and Class C with ordinary No. 30 felt. If the proposal does not name the underlayment from the correct row of that report, the class is not specified — whatever the brochure says.
Common belief
Class 4 impact resistance means it will survive hail.
What is actually true
UL 2218 states in its own scope that it “does not evaluate the effect of weathering, temperature, aging or similar effects,” and IBHS observes that the whole family of standards evaluates new products. A Class 4 classification is a laboratory result on a new specimen, not a forecast about a storm on a twenty-year-old roof. It may still be worth having, and it may still earn an insurance discount. It is not a promise.
Common belief
It's code approved, so it is approved everywhere.
What is actually true
Evaluation reports name the code editions they address, and carry separate supplements for jurisdictions such as California, Los Angeles and Florida. Florida additionally runs its own product approval system with a public search by FL number and manufacturer. And the acceptance of an alternative material is granted by a code official, typically for the specific project in front of them.
Common belief
It's made from recycled material, so it is the sustainable choice.
What is actually true
Recycled content is a sourcing fact, not a durability fact, and it cuts both ways: the same reports that record recycled polyolefin or post-consumer rubber content are the reports that had to demonstrate property retention after accelerated weathering. The FTC’s Green Guides treat an unqualified recycled-content claim as appropriate only where the entire product, excluding minor incidental components, is made from recycled material; anything less should be clearly qualified. Ask what fraction, ask pre- or post-consumer, and ask separately about durability.
Common belief
Synthetic means maintenance free.
What is actually true
It means a different maintenance profile, not the absence of one. Debris still dams in valleys, moss and algae still grow in wet climates, sealant at flashings still has a service life, and walking a moulded roof is a question the manufacturer answers rather than the crew. Several of those maintenance acts are constrained by the warranty document.

How it actually fails

The assembly on the roof is not the assembly in the report: The tile is the specified product but the underlayment, the fastener, or the exposure is not. Every tested value in the report — fire classification, uplift pressure — belongs to the combination that was tested. One report permits only the manufacturer’s specified fasteners; another prices its Class A classification on two named underlayment products.What you can see: Nothing visible from the ground, ever. This is found in the paperwork or not at all: the delivery tickets, the pre-cover photographs, and the row of the report’s table that the proposal cites. Ask for all three before the covering goes on.
Ultraviolet and thermal degradation of the polymer: The two things the acceptance criterion tests for — property loss after xenon-arc exposure, and temperature cycling — are the two things a roof does to a polymer for its whole life. This is the category’s defining long-term unknown rather than a defect: the tests exist because the mechanism is real, and the field measurements that would quantify it at twenty or thirty years have not been published.What you can see: Colour shift, surface chalking, and units that look different at the sunny end of a roof from the shaded end. Brittleness is not visible; it announces itself when someone walks the roof or when hail arrives.
Fire classification quietly downgraded by a substitution or a repair: Ordinary felt goes down instead of the named underlayment, or a later repair opens the assembly and closes it with whatever was on the truck. The covering is unchanged and the classification of that area is not what the file says.What you can see: Invisible. The only evidence is documentary: the underlayment product name on the material invoice, and the photographs taken before the tiles went down.
Repair matching failure: A profile is revised or discontinued, or the field has weathered away from the new stock. A patch that is structurally correct is cosmetically obvious, which matters most on exactly the roofs where appearance was the reason for buying the product.What you can see: A visibly newer patch. Ask, before purchase, how long the manufacturer commits to supplying the profile and colour, and get the answer in writing rather than in conversation.
The warrantor stops existing: The company that wrote a fifty-year promise fails in year twelve. The promise becomes a general unsecured claim, behind secured creditors, priority claims and administrative expenses.What you can see: A returned letter, a dead phone number, or a successor company that acquired the assets but not the liabilities. There is no roof-side symptom at all — which is why this belongs in the purchase decision rather than the maintenance plan.
An expired or superseded evaluation report at exactly the wrong moment: The report the product was sold on has lapsed, or addresses a code edition the jurisdiction no longer uses. It usually surfaces when a permit is pulled, an insurer asks, or a buyer’s inspector asks during a sale.What you can see: A permit query, an insurance question, or an inspection report item. All three issuing bodies publish current status in free public directories, so this is checkable in minutes at any point in the roof’s life.

Sources and further readingSection link

Understanding Roofing / Published August 14, 2026 / Updated August 26, 2026

Scope and limitations

It does not publish a service-life figure for composite roofing, and will not until there is observed field service to base one on.
The longest independently measured outdoor weathering available for any roof product is the Cool Roof Rating Council's three-year aged rating, and that measures optical properties rather than watertightness.
It does not publish a cost figure.
Composite pricing is product-specific, installer-thin in most markets, and there is no transparent national dataset that separates it from the rest of a roofing job.
The section on money explains what actually decides the number instead.
The three products examined here were chosen because their evaluation documents are published in full and are free to read.
They are not a survey, not a sample, and not a recommendation.
Every statement made about them is a statement about those documents, on the dates recorded below, and not about the products' performance on a roof.
It cannot tell you what your jurisdiction requires.
Code references here are to model text and to product-specific evaluation reports; your adopted edition, its amendments, and your authority having jurisdiction govern, and acceptance of an alternative material is typically granted project by project.
It cannot tell you whether a manufacturer will exist when you need it.
Nobody can.
The page explains what a warranty is worth if one does not, rather than pretending the question is answerable.
It found no U.S.
Department of Energy Building America Solution Center resource guide for steep-slope polymer composite coverings, equivalent to the ones that exist for asphalt shingle, metal and low-slope roofs (site search, 14 August 2026).
The absence of independent government building-science guidance for this category is itself part of the picture, and it is the reason this page leans on product evaluation documents and standards text rather than on a synthesis somebody else has already written.
Its account of the 1990s cement-fibre shake litigation goes only as far as a Weyerhaeuser SEC filing supports it: that the class action existed, what it was about, and that an insurance settlement followed in 2003.
No government or court-published record of the case could be located online, so the class size, the settlement totals and the failure mechanism that circulate widely on commercial and law-firm pages are deliberately not published here.
The warranty and consumer-law passages describe federal disclosure rules and bankruptcy priority in general terms.
They are not legal advice, rights and remedies vary by jurisdiction and by facts, and this page has not yet had legal review.

2024 International Residential Code, Chapter 9: Roof Assemblies — R902.1, R905.1.1, R905.2 through R905.15, R905.6.4
International Code Council, Digital Codes — model code text / 2024 edition
That Class A, B and C roof assemblies are tested in accordance with ASTM E108 or UL 790; the complete list of roof coverings R905 gives prescriptive requirements for, which contains no polymer or composite section; that the chapter's covering list names “slate and slate-type shingles” and directs them to R905.6; and that R905.6.4 requires slate shingles to comply with ASTM C406, a natural-stone specification a moulded polymer cannot meet.
Model-code text published by the code-development body, not adopted law. It is not the law in any jurisdiction until that jurisdiction adopts it, and adoptions routinely amend it. Confirm the adopted edition, its amendments, and its effective date with your authority having jurisdiction.
2021 International Residential Code, Section R104.11 — Alternative materials, design and methods of construction and equipment
International Code Council, Digital Codes — model code text / 2021 edition; the same provision appears at R104.11 in the 2015 and 2018 editions
That the building official has the authority to approve an alternative material, design or method of construction on application, on finding that it complies with the intent of the code and is, for the purpose intended, not less than the equivalent of that prescribed in the code in quality, strength, effectiveness, fire resistance, durability and safety; and that the official may require tests as evidence of compliance, at no expense to the jurisdiction.
Model-code text, not adopted law, and the section number is not stable: the 2024-cycle International Building Code carries the same provision at Section 104.2.3. Which text governs, and whether it has been amended, is a question for your authority having jurisdiction.
2024 International Building Code, Chapter 1 — Section 104.2.3, Alternative materials, design and methods of construction and equipment
International Code Council, Digital Codes — model code text / 2024 edition
That in the 2024-cycle model International Building Code the alternative-materials provision is numbered Section 104.2.3, with the equivalency criteria in its own subsection — the renumbering this page cites as a reason to check your jurisdiction's adopted text rather than a section number quoted anywhere.
Model-code text, not adopted law. A jurisdiction on the 2021 or an earlier cycle will still be numbering this provision 104.11 or R104.11.
ICC-ES Evaluation Report ESR-4756 — Brava One Cedar Shake and Brava One Slate Roofing Tiles
ICC Evaluation Service, LLC / Issued November 2025; subject to renewal November 2026
That the products are polymer-based tiles of a proprietary formulation, classified under CSI section 07 32 26 Plastic Roof Tiles; installed weights of 304 and 310 lb per 100 sq ft; a 4:12 minimum slope; evaluation under ICC-ES AC07 dated February 2014, editorially revised January 2021; Class A classification only with one of two named proprietary underlayments and Class C with ASTM D226 Type II No. 30 felt; allowable uplift of 196 psf with screws, being the tested ultimate pressure divided by a safety factor of 2, and a 130 mph Exposure B limitation with nails; that allowable design uplift must be determined by a registered design professional; that reroofing requires complete removal of the existing covering and underlayment; the California supplement covering Fire Hazard Severity Zones and Wildland-Urban Interface Fire Areas; and the report's own statement that it is not an endorsement or a recommendation for use.
Product-specific. It addresses the 2021 and 2018 IBC and IRC, with separate supplements for Los Angeles, California and Florida, and it expires. Nothing in it transfers to any other manufacturer's product, and ICC-ES states expressly that there is no warranty by ICC-ES as to any finding in the report.
UL Evaluation Report UL ER18920-01 — EcoStar Empire Shake, Empire Plus Shake, Empire Slate and Empire Niagara Slate polyolefin composite tiles
UL LLC (copy published by EcoStar LLC) / Issued 15 August 2014; revised 5 August 2021
That the tiles are manufactured using virgin and recycled polyolefin polymers, classified under CSI sections 07 31 53 Plastic Shakes and 07 32 26 Plastic Roof Tiles; evaluation under ICC-ES AC07 and AC10; testing of tensile properties to ASTM D638 and flexural properties to ASTM D790 both as manufactured and xenon-arc weathered, plus temperature cycling; a 3:12 minimum slope with exposure-dependent limits; that existing roof covering materials are to be removed before installation; that only the manufacturer's specified fasteners may be used; that allowable uplift uses a safety factor of 2.0 and covers the roof system only, with deck and framing designed separately; that UL 2218 impact classification is a separate UL certification to be looked up in the directory; that approval of building products is the responsibility of the authorities having jurisdiction; and that a UL Evaluation Report must not be used in a way implying endorsement.
Product-specific, and read from the copy the manufacturer publishes. Its scope of evaluation covers the 2012, 2009 and 2006 IBC and IRC and no later edition. The report itself directs readers to UL's Product iQ database for its current status, which is where status should be confirmed rather than from any hosted copy.
QAI Code Evaluation Report CERus-1013 — G.E.M. Inc (Euroshield) Ranchland Shake, Rundle Slate, Beaumont Shake, Beaumont Shake HP, Vermont Slate Loc and Vermont Slate Loc HP
QAI Laboratories / Published November 2022; revised December 2025; expires March 2027
That the products are composite roof coverings molded from a proprietary formulation including post-consumer waste recycled rubber and additives, classified under CSI section 07 31 33 Composite Rubber Shingles; approval for use in Class C roof assemblies only; Class IV impact resistance evaluated following UL 2218; installed weights of 2.1 to 3.4 lb per square foot; a 4:12 to 20:12 slope range; a spontaneous ignition temperature at or above 650 °F to ASTM D1929 and a CC2 rate of burning to ASTM D635; that installation over existing construction requires the existing coverings and underlayment to have been removed; and evaluation against ICC-ES AC07 with supporting data showing no loss of tensile strength after aging to ASTM G155.
Product-specific, and it expires. Read alongside the March 2024 edition of the same report number (also published by QAI), which covers four products rather than six and lists the 2024 IBC and IRC on its cover where the December 2025 edition does not — a reminder that a report number alone does not tell you what a document currently says.
UL 2218, Standard for Impact Resistance of Prepared Roof Covering Materials
UL Standards & Engagement / Edition 2, published 25 January 2010; last revised 28 May 2024
The scope of the impact-resistance test method for prepared steep-slope roof covering materials, and its own statement that it does not evaluate the effect of weathering, temperature, aging or similar effects on impact resistance.
A standards catalogue entry. The full standard is a purchased document; the scope statement quoted here is what the catalogue publishes. It says nothing about how any particular product performed.
Roof 101 — impact resistance ratings and hail testing
Insurance Institute for Business & Home Safety
The UL 2218 pass criterion — no crack visible on the back of the specimen after two impacts in the same location; that IBHS's own impact test evaluates deformation, granule loss and breaches rather than pass or fail; and that these standards evaluate new products and do not account for the effects of weathering, temperature, aging or similar factors.
Written primarily around asphalt shingles and around insurance-relevant hail performance. It is not a product listing and it is not a code determination.
Measurement Science Tools for Accelerated Weathering of Polymers Project
U.S. National Institute of Standards and Technology
That the development of service life prediction tools from accelerated weathering is difficult because of the differences between outdoor and indoor exposure conditions — ultraviolet spectrum, ultraviolet intensity, and moisture and temperature variability — and that building a validated correlation is an active national research programme rather than settled practice.
A research programme description covering polymers generally. It is not about roofing products specifically and it does not evaluate any product.
Roof Rating Program — initial and three-year aged radiative property ratings
Cool Roof Rating Council
That rated products carry initial and three-year-aged solar reflectance, thermal emittance and Solar Reflectance Index values; that aged values come from natural weathering at approved test farms in Arizona, Ohio and Florida chosen to represent hot-dry, cold-temperate and hot-humid climates; that interim laboratory-aged Rapid Ratings are displayed until the three-year exposure completes; and that placement on the directory does not by itself mean a product is “cool” under any code, standard or programme.
A radiative-property rating programme. It measures reflectance and emittance, not watertightness, strength, or service life, and a three-year aged value is not a statement about year thirty.
16 CFR 701.3 — Written warranty terms
U.S. Federal Trade Commission, via the U.S. Government Publishing Office / 2023 CFR edition
The disclosures a written warranty on a consumer product costing more than $15 must make in a single document: who it runs to, what is covered and excluded, what the warrantor will do, when the term begins and how long it lasts, the step-by-step claim procedure and contact details, informal dispute mechanisms, limitations on implied warranties and on consequential damages, and the statement that the warranty gives specific legal rights which vary from State to State.
A federal disclosure rule, not a guarantee of any outcome. It governs what a warranty must say, not what it must cover, and state law adds rights and remedies that vary.
16 CFR 700.1 — Products covered by the Magnuson-Moss Warranty Act
U.S. Federal Trade Commission, via the U.S. Government Publishing Office / 2023 CFR edition
That roofing and other structural components of a dwelling are not consumer products when sold as part of real estate covered by a written warranty, or when integrated into a home a consumer contracts with a builder to construct; and that roofing and similar materials purchased separately for home improvement or repair are consumer products under the Act.
An interpretive rule. Whether it applies to a particular transaction is a fact-specific legal question, and nothing on this page is legal advice.
16 CFR 260.13 — Recycled content claims (Green Guides)
U.S. Federal Trade Commission, via the U.S. Government Publishing Office / 2023 CFR edition
That it is deceptive to misrepresent that a product is made of recycled content; that recycled content means material recovered or diverted from the waste stream pre-consumer or post-consumer; and that an unqualified recycled content claim is appropriate only where the entire product or package, excluding minor incidental components, is made from recycled material.
An advertising guide. It governs how a claim may be made, and says nothing about whether recycled content helps or harms durability.
Chapter 7 — Bankruptcy Basics
Administrative Office of the U.S. Courts
That section 726 of the Bankruptcy Code creates six classes of claim and that each class must be paid in full before the next lower class is paid anything; that unsecured debts are extended on an evaluation of ability to pay rather than on collateral; and that most individual Chapter 7 cases are no-asset cases producing no distribution to unsecured creditors.
A plain-language court publication about consumer and business bankruptcy generally. It is not advice about any company, any warranty, or any claim, and corporate reorganisations differ from liquidations.
Consider alternatives
Mark S. Graham, Professional Roofing (National Roofing Contractors Association) / 1 April 2019
That a code official may accept an alternative material found not less than the equivalent prescribed in the code in quality, strength, durability, effectiveness, fire resistance and safety; that evaluation reports from recognised sources such as ICC Evaluation Service and UL are the usual evidence, and typically specify the applicable code edition and any use limitations; and that such acceptances typically apply only to the specific project for which they were granted.
Trade guidance written for roofing professionals against the code editions current in 2019. It is not adopted law, and section numbering has changed since.
Product Approval search
Florida Department of Business and Professional Regulation, Florida Building Code Online
That Florida operates a public, searchable statewide product approval system in which a roofing product can be looked up by FL number, manufacturer, code version and application type — an example of a jurisdiction-specific approval regime that sits alongside, and is not replaced by, a model-code evaluation report.
Florida only. It says nothing about any other state, and Miami-Dade County operates a separate Notice of Acceptance system with additional requirements.
How do I know if I have asbestos in my home?
U.S. Environmental Protection Agency
That home products including shingles may contain asbestos; that EPA recommends testing suspect materials where they are damaged or where a renovation would disturb them; and that samples should be taken by a properly trained and accredited asbestos professional.
General homeowner guidance. It does not identify which specific roofing products contain asbestos, and state and local rules on testing, notification and disposal vary.
Fall Protection in Residential Construction
U.S. Occupational Safety and Health Administration
That falls are the leading cause of death for workers engaged in residential construction, and that workers engaged in residential construction six feet or more above lower levels must be protected by conventional fall protection.
An occupational-safety standard for employers and workers. It is not homeowner guidance, and the fact that trained workers use fall protection is a reason for an untrained reader to stay off the roof entirely, not a procedure to copy.
Weyerhaeuser Company Form 10-Q for the quarter ended 28 September 2003 — Note 14, Other operating costs, net
Weyerhaeuser Company, filed with the U.S. Securities and Exchange Commission (EDGAR) / Filed 10 November 2003
That American Cemwood Corporation, a subsidiary of MacMillan Bloedel Limited which Weyerhaeuser had acquired, settled a class action in 1999 involving claims alleging the failure of its cement fibre roofing products, and that Weyerhaeuser recognised a $25 million net pre-tax benefit in the second quarter of 2003 from a settlement with Cemwood's insurance companies.
A company's own quarterly filing, not a court record. It establishes that the litigation and the insurance settlement happened and what they were about; it states no class size, no settlement total, and nothing about the failure mechanism. No government or court-published record of the underlying litigation could be located online, which is why the widely repeated class-size and settlement figures are not published on this page.

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