The 2026 Roofing Material Carbon and Embodied Energy Report: Asphalt, Metal, Tile, Slate, and Synthetic Compared

The roofing material carbon report 2026 aggregates verified Environmental Product Declarations (EPDs), EPA Waste Reduction Model (WARM) v16 emission factors, Cool Roof Rating Council (CRRC) reflectance data, Department of Energy (DOE) cool-roof guidance, and National Asphalt Pavement Association (NAPA) recycling survey results into one citable reference. The point is to settle, with named primary sources, what asphalt, metal, tile, slate, synthetic slate, and commercial single-ply membranes actually cost the atmosphere on a per-square-foot, per-year-of-service basis. Most of the embodied-carbon claims floating around contractor blogs and AI Overviews come from secondary aggregators that never cite a verified EPD or WARM number. This report cites the underlying documents directly.

Methodology and sources

This report aggregates published, third-party-verified Type III EPDs from NSF Certification, UL Environment, and ASTM International, along with the EPA Waste Reduction Model (WARM) v16 December 2023 release for end-of-life GHG accounting. Where manufacturer EPDs cover only A1-A3 (cradle-to-gate), we report those values and note the boundary. Embodied energy is reported as the EPD ADP-fossil indicator (MJ, net calorific value). For natural slate, clay tile, and synthetic slate, where verified North American EPDs are scarce, we cross-reference Historic England’s Embodied Carbon of Roofing Slate series, the MDPI 2026 EPD profile study, and academic LCA work (Springer 2018). SRI and aged solar reflectance values come from the CRRC Rated Products Directory and the CRRC SRI guidance document (April 2024). Cooling energy-savings ranges come from DOE Energy Saver and the Lawrence Berkeley National Laboratory cooling-energy study.

Why roofing material carbon matters: 11 million tons of US shingle waste annually

EPA WARM v16 documentation (December 2023, EPA-530-R-23-020) cites the long-standing US generation figure of approximately 11 million short tons of asphalt shingle waste per year, originally from the Northeast Recycling Council 2007 fact sheet and still the working number in EPA’s life-cycle inventory. That is roughly the mass of every US-built passenger vehicle sold in a typical 2-month period, except it lands in construction and demolition (C&D) landfills rather than scrap. Asphalt shingles are 82% fiberglass-based in the residential market (HUD Rehab Guide Vol. 3) and 22% asphalt cement by mass on average, per the WARM v16 composition table.

The carbon-footprint conversation has historically been dominated by operational-energy questions (R-value, HVAC efficiency, cool-roof reflectance) because operational emissions over a building’s life dwarfed embodied emissions. As building envelopes get tighter and grids get cleaner, that ratio inverts. Roofing is a large building-envelope mass category that cycles every 15 to 30 years (asphalt) or 50 to 100+ years (slate, tile, metal). The relevant question becomes not just “what’s the GWP of this product?” but “what’s the GWP per year of service life?”

That matters because asphalt has the lowest absolute embodied carbon per square foot of any common pitched-roof material but the shortest realistic lifespan. The lifespan-weighted comparison reorders the rankings substantially, and we tabulate it below. For broader lifespan context, see our 2026 Roofing Material Lifespan Report and how long does a roof last.

Embodied energy by material (MJ/sq ft installed)

The table below converts cradle-to-gate ADP-fossil and non-renewable primary energy figures from verified EPDs (where available) to a US per-square-foot basis (1 m² = 10.764 sq ft). For materials without a North American EPD, we cite the best-available academic LCA or industry-published range. All values are A1-A3 unless noted.

Conversion note: NSF EPD10397 reports ADP-fossil of 146 MJ per m² (A1-A3) for GAF Timberline HDZ, equivalent to 13.56 MJ per sq ft. UL EPD 4789400789.101.1 reports 18.8 MJ per m² (TRACI ADP-fossil); the broader NRPRE plus NRPRM totals 134.6 MJ per m² for Duration, equivalent to 17.47 MJ per sq ft. Carlisle ASTM-EPD425 60-mil TPO reports 70.3 MJ NRPRE plus 39.5 MJ NRPRM (A1-A3), totaling 109.8 MJ per m² (10.20 MJ per sq ft). Metal, tile, and slate ranges reflect the spread across multiple LCA studies and transport-distance variability (a major driver for slate, often imported from Spain or Wales).

Asphalt shingles: dominant market share, dominant waste stream

Asphalt shingles cover roughly 75 to 80% of US pitched-roof installations and dominate the residential roofing carbon conversation by sheer mass. The two largest US producers, GAF and Owens Corning, have both published product-specific EPDs for their flagship architectural lines. Both EPDs are independently verified (NSF Certification chaired by Dr. Thomas Gloria for GAF; UL Environment with Grant R. Martin for Owens Corning) and use ISO 14025 and 21930:2017 Part B PCRs (UL 10010-11) for asphalt shingles.

The 11 million tons of US asphalt shingle waste per year

The 11-million-ton figure originates from the Northeast Recycling Council and is carried forward in EPA WARM v16 (Section 2.1). About 90% of post-consumer shingle waste comes from residential tear-offs; the remainder is manufacturer scrap and commercial removals. EPA’s WARM v16 model assigns a net landfill emission factor of +0.02 MTCO2e per short ton of asphalt shingles landfilled (transport plus operating equipment only; shingles are biologically inert and produce no landfill methane).

By contrast, recycling into hot-mix asphalt (HMA) carries a net emission factor of -0.09 MTCO2e per ton (offsetting virgin asphalt binder and aggregate, less 7.2% process loss). Combustion in cement kilns scores even better at -0.35 MTCO2e per ton because asphalt shingles contain about 22% asphalt cement by weight (carbon-rich binder) that displaces refinery fuel gas; WARM v16 Exhibit 2-17 models this displacement using 8.8 million Btu per ton of fiberglass shingles versus 37.5 million Btu per ton of refinery fuel gas.

Asphalt shingle recycling (RAS) economics

NAPA’s 2024 Asphalt Pavement Industry Survey reports an equivalent of approximately 256,400 residential roofs were recycled into pavement in 2024. RAS usage was reported in 20 states; top consumers were Illinois, North Carolina, Wisconsin, Massachusetts, Alabama, Arkansas, Texas, Florida, Pennsylvania, and Kentucky. Typical RAS application is 5% by weight of the hot-mix; state DOT specifications often cap at 3 to 5%.

The Asphalt Roofing Manufacturers Association (ARMA) has supported expanding RAS markets for over a decade, but per-roof economics depend on local landfill tipping fees versus shingle-grinding processing fees. High-tipping-fee markets (Northeast, urban California) make recycling competitive; cheap-landfill markets default to C&D disposal. See 2026 roofing cost report and asphalt shingle roof lifespan.

Metal roofing: highest recycled content, highest recyclability

The Metal Construction Association (MCA) Technical Bulletin on Recycled Content of Metal Roofing and Siding Panels reports that steel metal roofing carries a minimum 25% recycled content, with individual product lines reaching 95%. Approximately 90% of US metal roofs and insulated metal panels are steel. The MCA bulletin notes that steel is 100% recyclable without quality loss and that recycling steel requires approximately 26% of the energy required to produce steel from virgin ore. The Metal Roofing Alliance reinforces this with end-of-life scrap-value data: a torn-off metal roof has positive salvage value at a recycler, where a torn-off asphalt roof carries negative value (landfill tipping fee).

The cradle-to-gate carbon penalty for virgin steel is real (roughly 1.85 t CO2e per ton globally per worldsteel LCI), but recycled-content fraction in 24-gauge Galvalume offsets a substantial portion. Standing-seam Galvalume with 75-PVDF Kynar 500 finish averages 28 to 38 MJ per sq ft and 0.55 to 0.85 kg CO2e per sq ft. Aluminum standing seam carries higher absolute embodied carbon because primary aluminum production is electricity-intensive, but secondary aluminum runs about 5% of primary energy intensity.

The cool-roof angle compounds the metal advantage: standing-seam metal can be specified in CRRC-rated Kynar colors with aged solar reflectance up to 0.65 and SRI 40 to 80. See metal vs asphalt shingle roof and standing-seam metal roof cost.

Tile and slate: highest embodied energy, longest lifespan

Concrete tile, clay tile, and natural slate sit at the high-mass end of the pitched-roof category. Concrete tile averages 9 to 11 pounds per sq ft installed; clay tile runs 10 to 12 pounds; slate runs 8 to 10 pounds. The mass alone drives embodied energy upward (more material to mine, fire, and transport).

Concrete tile EPD work draws on NRMCA industry-average concrete EPD methodology and the broader concrete-cement carbon-intensity literature. Module A1 (raw materials, dominated by Portland cement) accounts for the bulk of the impact. The Springer 2018 LCA assessment of roof-covering materials puts concrete tile in the 38 to 52 MJ per sq ft and 0.95 to 1.40 kg CO2e per sq ft range, dominated by cement clinker.

Clay tile is higher still on absolute embodied carbon because the firing process is thermally intensive (kiln temperatures of 1,000 to 1,200°C). The 2026 MDPI EPD profile study covering ceramic tiles and clay roofing tiles puts production energy at 2.1 to 2.4 MJ per kg of finished tile, with kiln efficiency the dominant variable. Marley’s third-party-verified clay tile EPD reports 7.05 kg CO2e per m² cradle-to-gate (0.655 kg per sq ft); industry-average ranges run higher.

Natural slate is the special case. Historic England’s embodied-carbon webinar series cites high-quality slate (Welsh, Spanish, or Vermont) at embodied carbon as low as 0.15 to 1.0 kg CO2 per m² (0.014 to 0.093 kg per sq ft) because the material is essentially split-and-trimmed stone with minimal processing. Most of the lifecycle impact for slate is transportation; a Welsh slate roof on a Boston townhouse carries meaningfully more carbon than the same slate on a Cardiff townhouse. Annualized over a 100-year service life, slate’s lifespan-weighted carbon intensity is the lowest of any common roofing material, including cedar shake.

The catch: slate’s high upfront cost (typically $25 to $50+ per sq ft installed in the US, two to four times metal) means most US homeowners do not get the carbon-amortization benefit because the upfront cost gates access. For context on tile and natural roof materials, see our residential roofing guide.

Synthetic slate and shake: the polymer composite tradeoff

Synthetic slate (Brava, DaVinci Roofscapes, EcoStar, Inspire) replaces quarried stone with polymer-composite tiles of virgin resins, recycled polymer, and mineral fillers. DaVinci products are LEED WUI Approved and the manufacturer reports 100% recyclability through a job-site take-back program. EcoStar carries a published EPD covering its Majestic, Empire, and Niagara lines.

The carbon math is mixed. Synthetic slate dodges the transport-distance penalty of imported natural slate (most synthetic is North American), avoids clay-tile kiln intensity, and avoids concrete tile’s cement-clinker penalty. Springer 2018 LCA work puts synthetic slate at 28 to 42 MJ per sq ft and 0.65 to 0.95 kg CO2e per sq ft cradle-to-gate. The end-of-life question is open: at-scale recycling infrastructure for tear-off synthetic slate does not yet exist in most US markets. Realistic 40 to 50-year service life lands these products between asphalt and natural slate on a lifespan-weighted basis.

Commercial membranes: TPO, EPDM, PVC, modified bitumen carbon profiles

Single-Ply Roofing Industry (SPRI) members publish standardized EPDs through ASTM International. The Carlisle Construction Materials Sure-Weld TPO EPD (ASTM-EPD425, issued May 2023) covers 45-, 60-, and 80-mil membrane thicknesses produced at three North American sites (Carlisle PA, Senatobia MS, Tooele UT). The 60-mil A1-A3 GWP is 3.77 kg CO2e per m² of installed membrane at 1.62 kg per m² mass. Raw materials (A1) account for the lion’s share of impact at 3.37 kg CO2e per m² of the 3.77 total.

EPDM industry-average EPDs (covered by SPRI members Carlisle, Holcim Building Envelope, IKO Industries, and Johns Manville) for 60-mil non-reinforced EPDM run in the same general band as TPO: 0.32 to 0.55 kg CO2e per sq ft cradle-to-gate. EPDM uses ethylene-propylene-diene monomer base resin, which has different upstream feedstock chemistry than TPO’s polypropylene-ethylene base, but the finished-product carbon intensity lands close.

PVC membranes (Sika Sarnafil S 327 and G 410, Carlisle Sure-Flex, GAF EverGuard) carry higher A1 burden because PVC resin production from chlorine and ethylene is more energy- and emission-intensive than polyolefin chemistry. Sika was the first thermoplastic roofing manufacturer to publish a cradle-to-grave (not just cradle-to-gate) EPD, covering the full life cycle. The 60-mil PVC band runs 0.45 to 0.65 kg CO2e per sq ft.

Modified bitumen (SBS or APP-modified asphalt, typically 2-ply) is closer to the asphalt-shingle chemistry, with embodied energy and GWP scaling with the asphalt cement fraction. WARM v16 does not break out modified-bitumen separately, so most LCA work uses the asphalt shingles chapter as proxy methodology. For commercial product cost context, see TPO vs EPDM roofing, TPO vs PVC membrane, modified bitumen roof, and flat roof materials compared.

The cool roof carbon picture: operational impact

The embodied-carbon conversation only tells half the story. A cool roof reduces the air-conditioning load on the building below it, generating operational-carbon savings that compound year over year. The DOE Energy Saver “Cool Roofs” guidance reports that a cool roof can reduce cooling energy demand by up to 15% on a single-story building. The 2010 Lawrence Berkeley National Laboratory study (Levinson and Akbari) on cooling-energy savings potential for light-colored roofs across 11 US metropolitan areas put annual energy savings at up to $0.05 per sq ft, with the biggest savings in hot and warm climate zones.

The CRRC defines SRI on a 0-to-100 reference scale where 0 is a standard black (solar reflectance 0.05, thermal emittance 0.90) and 100 is a standard white (solar reflectance 0.80, thermal emittance 0.90). White TPO and PVC commonly exceed SRI 100 (i.e., they reject more heat than the SRI reference white) because their measured thermal emittance is at or above 0.90 and their aged solar reflectance approaches 0.80. For color-driven roof-temperature context, see our best roof color guide.

Lifespan-weighted carbon: the real comparison

Annualized GWP (A1-A3 GWP divided by realistic service life in years) is the comparison that reorders the rankings. A 20-year asphalt roof at 0.35 kg CO2e per sq ft annualizes to roughly 17.5 g per sq ft per year. A 100-year slate roof at 0.10 kg CO2e per sq ft annualizes to 1.0 g per sq ft per year. Slate wins by an order of magnitude on a lifespan-weighted basis despite carrying nominally higher absolute carbon.

Caveats: service-life assumptions matter, and we use real-world numbers, not warranty headlines. Asphalt manufacturers warranty for “lifetime” but realistic full-system service life is 18 to 25 years; Class 4 impact-resistant shingles stretch that on the high end. Metal can last 60 to 80 years when properly installed but most retrofits get cycled at 40 to 50. Concrete tile is durable (60+ years for the tile itself) but underlying underlayment usually requires replacement at 30 to 40 years. Use these annualized numbers as planning baselines, not warranty arguments.

End-of-life waste streams

The end-of-life carbon profile differs sharply by material. Asphalt’s 22% asphalt-cement fraction makes it a candidate for cement-kiln combustion (energy recovery offsets refinery fuel gas) or for RAS incorporation into hot-mix pavement. Metal goes back through scrap-recycling channels at positive value. Tile, slate, and synthetic slate face a thinner recycling infrastructure: most ends up in C&D landfill, though tile is occasionally crushed for landscape aggregate or reused in restoration projects. EPDM, TPO, and PVC have manufacturer take-back programs (Carlisle Sure-Weld TPO is the most mature), but the at-scale single-ply recycling network for tear-off membrane is limited.

For perspective on the asphalt tear-off-and-reroof flow that feeds this stream, see our tear-off and reroof pricing piece. The C&D landfill destination is also where most underlayment, flashing, and miscellaneous accessories end up regardless of primary material.

Section 25C residential energy credit eligibility

The federal Section 25C Energy Efficient Home Improvement Credit historically included a cool-roof provision covering “any metal roof or asphalt roof installed on a dwelling unit, but only if such roof has appropriate pigmented coatings or cooling granules which are specifically and primarily designed to reduce the heat gain of such dwelling unit.” Both the cool-roof eligibility and the broader 25C credit were modified by subsequent legislation. Per the 2025 reconciliation amendments, the Section 25C credit expired effective December 31, 2025 (note: cool-roof eligibility for metal and asphalt shingles was actually removed in the IRS 2023 Form 1040 instructions, ahead of the broader credit sunset), meaning installations placed in service in 2026 or later are not eligible for the federal credit absent new legislation.

Many state and utility-level programs continue to offer cool-roof rebates independent of federal status. The California Energy Commission and several investor-owned utility programs (PG&E, SDG&E, SCE) provide rebates for CRRC-rated roof installations under their own statutory frameworks. For solar context, see our solar roof tax credit 2026 piece and the standalone is new roof tax deductible primer.

California Title 24 cool roof requirements (2025 update)

California’s Title 24 2025 Building Energy Efficiency Standards (effective January 1, 2026) update the mandatory and prescriptive cool-roof requirements. For single-family residential and nonresidential prescriptive paths, the aged solar reflectance, thermal emittance, and SRI requirements did not change in the 2025 update. The 2025 cycle did expand multifamily Option D coverage to additional climate zones and tightened the multifamily steep-slope Option B value to 0.25 aged solar reflectance, 0.75 thermal emittance, SRI 23 in climate zones 10, 11, 13, and 15.

Climate zones 10 through 15 (Inland Southern California, the Central Valley, and the high desert) carry the most demanding cool-roof requirements. Compliance can be achieved via the prescriptive path (select a CRRC-rated product meeting the minimum aged SR and TE or SRI for the applicable climate zone, building type, and roof slope) or through whole-building energy modeling. The CRRC Rated Products Directory is the lookup of record.

The 2026 manufacturer EPD landscape

GAF announced in 2024 that it had scaled its EPD program to 21 product-specific EPDs covering shingles, polyiso insulation, and membrane products. Owens Corning publishes a product-transparency portal. CertainTeed runs the Sustainable Transparency Initiative. The pattern is that residential asphalt EPD coverage is now strong; commercial single-ply EPD coverage is strong; concrete and clay tile EPD coverage for the US market is uneven; and metal roofing relies more on industry-average steel and aluminum LCI data than on product-specific manufacturer EPDs.

What this means for specific audiences

For homeowners weighing sustainability

If budget tolerates it, slate and standing-seam metal are the lifespan-weighted carbon winners; metal also carries high recycled content and full end-of-life recyclability. If asphalt is the practical pick, choose an architectural shingle with a published EPD (GAF Timberline HDZ, Owens Corning Duration, CertainTeed Landmark) and specify a cool-rated color (Duration COOL, Timberline CS, Landmark Solaris). Avoid 3-tab when possible; the 15-year service life inflates annualized carbon. See metal roof cost for budget context.

For architects and specifiers

Use product-specific EPDs in your specification language, not industry averages. The spread between best-in-class and category-average shingles is roughly 10 to 12% on A1-A3 GWP (3.49 vs 3.88 kg CO2e per m² across the two major asphalt EPDs). On metal, demand recycled-content documentation from the coil supplier; 25% is the floor and 95% is achievable. Work from the CRRC Rated Products Directory directly for cool-roof compliance.

For commercial building owners

White TPO has become the default low-carbon, low-cost commercial single-ply for hot-climate cooling-load reduction. Carlisle Sure-Weld 60-mil at 3.77 kg CO2e per m² A1-A3 and SRI 104 to 115 leads on combined embodied plus operational footprint. For heating-dominated climates, EPDM remains the lowest absolute embodied-carbon choice. PVC carries the highest A1 burden of the single-plies but offers chemical resistance and weldable seam reliability. See flat roof materials compared.

Sources cited

1. NSF Certification. Environmental Product Declaration: GAF Timberline HDZ Shingles. Declaration EPD10397. Issued 7/29/2020. https://info.nsf.org/Certified/Sustain/ProdCert/EPD10397.pdf
2. UL Environment. Environmental Product Declaration: Owens Corning Asphalt Shingles (Supreme, Oakridge, Duration). Declaration 4789400789.101.1. Issued July 1, 2020. https://transparencycatalog.com/assets/uploads/default/EPD-Owens-Corning-UL-4789400789.101.1.pdf
3. ASTM International. Environmental Product Declaration: Carlisle TPO Single-Ply Roofing Membrane. Declaration ASTM-EPD425. Issued May 17, 2023. https://pcr-epd.s3.us-east-2.amazonaws.com/931.Carlisle_TPO_Reinforced_EPD_20230517.pdf
4. US Environmental Protection Agency. Documentation for Greenhouse Gas Emission and Energy Factors Used in the Waste Reduction Model (WARM): Construction Materials Chapters. EPA-530-R-23-020. December 2023. Asphalt Shingles chapter and Asphalt Concrete chapter. https://www.epa.gov/system/files/documents/2023-12/warm_construction_materials_v16_dec.pdf
5. US EPA. Waste Reduction Model (WARM) overview. https://www.epa.gov/waste-reduction-model/basic-information-about-waste-reduction-model
6. National Asphalt Pavement Association (NAPA). 2024 Asphalt Pavement Industry Survey on Recycled Materials and Warm-Mix Asphalt Usage. Published May 13, 2024. https://napanow.org/2024/05/13/napa-publishes-latest-recycling-wma-survey-results/
7. Asphalt Roofing Manufacturers Association (ARMA). Asphalt Shingle Recycling. https://www.asphaltroofing.org/asphalt-shingle-recycling-2/
8. Cool Roof Rating Council. California Energy Code (Title 24) cool-roof guidance. https://coolroofs.org/resources/california-title-24 and CRRC Rated Products Directory https://coolroofs.org/directory/roof
9. Cool Roof Rating Council. Solar Reflectance Index (SRI) Document. April 17, 2024. https://coolroofs.org/documents/CRRC-SRI-Document_2024-04-17.pdf
10. US Department of Energy. Cool Roofs. Energy Saver guidance. https://www.energy.gov/energysaver/cool-roofs
11. Lawrence Berkeley National Laboratory (Energy Technologies Area). Levinson, R., and Akbari, H. Cooling energy savings potential of light-colored roofs for residential and commercial buildings in 11 US metropolitan areas. https://eta.lbl.gov/publications/cooling-energy-savings-potential
12. Metal Construction Association. Technical Bulletin: Recycled Content of Metal Roofing and Siding Panels. https://metalconstruction.org/view/download.php/online-education/education-materials/edp-educational-files/recycled-content-of-metal-roofing-and-siding-panels
13. Metal Roofing Alliance. Recyclability. https://www.metalroofing.com/recyclability
14. Tile Roofing Industry Alliance. Durability and Longevity. https://www.tileroofing.org/durability–longevity.html
15. Historic England. Embodied Carbon of Roofing Slate. Webinar series. https://historicengland.org.uk/education/training-skills/training/webinars/recordings/embodied-carbon-of-roofing-slate/
16. SSQ Group. Sustainability of natural slate products. https://www.ssqgroup.com/about/sustainability
17. Khasreen et al, MDPI Architecture 2026. EPD Profiles of Ceramic Tiles, Sanitary Ware, Clay Roofing Tiles and Clay Bricks: Insights from One Click LCA and the International EPD System. https://www.mdpi.com/2673-4834/7/2/55
18. Springer (Clean Technologies and Environmental Policy). Carbon footprint and embodied energy assessment of roof-covering materials. 2018. https://link.springer.com/article/10.1007/s10098-018-1629-9
19. Internal Revenue Service. Energy Efficient Home Improvement Credit (Section 25C). https://www.irs.gov/credits-deductions/energy-efficient-home-improvement-credit
20. Single-Ply Roofing Industry (SPRI). Environmental Product Declarations section. https://www.spri.org/2023/07/spri-expands-website-to-include-environmental-product-declarations-epds/
21. DaVinci Roofscapes (Westlake Royal Building Products). Composite slate and shake roofing. https://www.westlakeroyalbuildingproducts.com/roofing/davinci-roofscapes
22. Sika Roofing. Sarnafil Product Transparency and Environmental Product Declarations. https://usa.sika.com/sarnafil/en/sustainability/environmental-product-declarations.html

Methodology note

EPDs from different programs (NSF, UL Environment, ASTM, EPD International) follow the same ISO 14025 and ISO 21930:2017 standards but may use different PCRs, LCA software, and LCI databases. EPD-to-EPD comparisons are technically permissible only when PCRs, declared units, system boundaries, and reference service lives align. Where we have used numbers from different EPDs side by side, we noted boundary scope (A1-A3 cradle-to-gate vs cradle-to-grave) and selected matching PCRs (UL 10010-11 for asphalt shingles; NSF 2019 sub-category PCR for single-ply membranes). For slate and clay tile, where North American product-specific EPDs are scarce, cited LCA literature provides working ranges. All source URL access dates are June 2026.