Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Total upfront embodied carbon
1,320.0
From concrete
600.0
From steel
720.0
kg CO2e per sq ft
8.8
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter concrete volume (cubic yards).
- 2Enter concrete gwp factor (kg CO2e/cy).
- 3Enter structural steel (tons).
- 4Enter steel gwp factor (kg CO2e/ton).
- 5Enter gross building area (sq ft).
- 6Read your total upfront embodied carbon on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Embodied carbon is the emissions baked into a material before it ever gets used — extraction, manufacturing, and transport — and for new construction it can rival or exceed a building's entire operational emissions over its first decade. This calculator estimates upfront (A1-A3) embodied carbon for the major structural material categories using published global warming potential factors per unit of material, then totals it into a project-level figure. Concrete and steel dominate most embodied carbon budgets because of the volumes used structurally; mass timber and low-carbon concrete mixes (with fly ash or slag cement replacement) can meaningfully cut the total. This is the calculation behind LEED v4.1 Materials & Resources whole-building LCA credits and increasingly behind local embodied-carbon ordinances (like those in several California and Colorado jurisdictions) that cap upfront carbon per square foot for new municipal and large commercial buildings.
Worked example
Using the values the calculator loads with:
Inputs
- Concrete volume: 2000 cubic yards
- Concrete GWP factor: 300 kg CO2e/cy
- Structural steel: 400 tons
- Steel GWP factor: 1800 kg CO2e/ton
- Gross building area: 150000 sq ft
Results
- Total upfront embodied carbon: 1,320
- From concrete: 600
- From steel: 720
- kg CO2e per sq ft: 8.8
What each field means
Inputs
- Concrete volume (cubic yards)
- The concrete volume used in the calculation, measured in cubic yards. Starts at 2000 cubic yards so you have a working example on load.
- Concrete GWP factor (kg CO2e/cy)
- The concrete gwp factor used in the calculation, measured in kg CO2e/cy. Starts at 300 kg CO2e/cy so you have a working example on load.
- Structural steel (tons)
- The structural steel used in the calculation, measured in tons. Starts at 400 tons so you have a working example on load.
- Steel GWP factor (kg CO2e/ton)
- The steel gwp factor used in the calculation, measured in kg CO2e/ton. Starts at 1800 kg CO2e/ton so you have a working example on load.
- Gross building area (sq ft)
- The gross building area used in the calculation, measured in sq ft. Starts at 150000 sq ft so you have a working example on load.
Results
- Total upfront embodied carbon
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- From concrete
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- From steel
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- kg CO2e per sq ft
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What's a good embodied carbon target per square foot?
Leading low-carbon commercial projects target 8-12 kg CO2e/sq ft for structure and enclosure; a conventional concrete-and-steel building typically lands 15-25+ kg CO2e/sq ft. Several city embodied-carbon ordinances (Colorado's HB21-1286-driven building codes, for example) are starting to set enforceable ceilings in this range for new large buildings.
How much does fly ash or slag replacement actually cut concrete's footprint?
Replacing 25-40% of Portland cement with fly ash or slag cement can cut a concrete mix's embodied carbon by roughly 20-40%, since cement clinker production is the dominant emissions source in concrete, not the aggregate or water. It's one of the cheapest embodied-carbon reduction levers available on a typical project.
Why does structural steel have such a high GWP factor per ton?
Steel GWP varies enormously by production route — electric arc furnace (recycled scrap) steel runs closer to 700-900 kg CO2e/ton, while basic oxygen furnace (virgin ore) steel runs 1,800-2,500+. Specifying EAF steel with high recycled content is one of the single highest-impact embodied-carbon decisions on a structural project.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
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Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Embodied Carbon of Materials Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/embodied-carbon-materials
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/embodied-carbon-materials" target="_blank" rel="noopener">Embodied Carbon of Materials Calculator — RevenueLab</a> (2026).</p>
Source: [Embodied Carbon of Materials Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/embodied-carbon-materials) (2026).