Relative indices for building materials across five common systems.
What you'll find here
This is a reference page, not a decision tool. Each material's Relative Carbon and Relative Cost are expressed as multiples of the best (lowest-impact) option in that system (= 1.0). A material with a Relative Carbon of 10 has roughly 10× the cradle-to-gate embodied carbon per square foot of the baseline in its system; a Relative Cost of 1.5 means 1.5× the installed cost of the cheapest option in that system.
Indices are per-system — a "1.0" in roofing is not equivalent to a "1.0" in facade. Use this page to look up values, understand bands, and see how options compare within a system. To build composite schemes and apply your own priorities, use the TCO+C Scorecard.
Materials in a system
Pick a system to see all materials within it, ranked by your selected metric. The colored bars use the Cividis colormap (colorblind-safe): gold indicates the best performance in the system on the selected metric (lowest carbon, lowest cost, or longest life), and midnight blue indicates the worst.
All materials
Every material in every system. Click column headers to sort. Use the filter box to narrow the list.
| System | Material | Rel. Carbon | Band | Rel. Cost | Band | Life (yrs) | Note |
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How these indices are built
Sources & calibration
Carbon indices are calibrated from the following sources:
Cost indices reflect typical installed first cost for U.S. commercial construction and should be treated as a comparative starting point. Substitute project-specific bid data when available. For procurement decisions on carbon, obtain product-specific Environmental Product Declarations (EPDs) — the EC3 tool by Building Transparency is the standard industry reference.
What is and isn't included
Included in the relative carbon index:
Excluded from the relative carbon index:
Service life is shown separately so users can reason about replacement cycles. A short-life material replaced multiple times over a building's lifespan can carry more total embodied carbon than a higher-index long-life option.
Carbon and Cost bands
Bands provide at-a-glance grouping for quick scanning. Each band reflects approximately the following percentile of materials within a system:
Because bands are per-system, a "Very Low" facade and a "Very Low" roofing system have different absolute carbon footprints. The band tells you relative position within its category, not absolute impact across the whole building.
Facade glazing options — how to combine
Glazing, Windows (punched) represents punched openings in an opaque wall and is intended to be combined with brick, panel, stone, or another opaque cladding (typical: 30–50% windows).
Glazing, Storefront represents ground-floor and retail glazing systems; less aluminum framing than curtain wall.
Glazing, Curtain Wall represents full-height structural glazing systems with substantial aluminum framing — typically the highest-carbon option in a facade.