What Is the Embodied Carbon of Building Materials?
Quick Answer
Concrete: ~100–150 kgCO&sub2;e/m³. Steel: ~1.5–2.5 kgCO&sub2;e/kg.
Timber is approximately carbon negative when sustainably sourced. Embodied carbon = cradle-to-gate emissions.
Embodied Carbon of Common Materials
- Concrete (C30): 100–150 kgCO&sub2;e/m³ (varies with cement content)
- Steel (structural sections): 1.5–2.5 kgCO&sub2;e/kg (~12,000–20,000 kgCO&sub2;e/m³)
- Bricks: 0.2–0.5 kgCO&sub2;e/kg
- Concrete blocks: 60–100 kgCO&sub2;e/m³
- Softwood timber: −0.7 to −1.0 kgCO&sub2;e/kg (carbon stored exceeds manufacturing emissions)
- Aluminium: 8–13 kgCO&sub2;e/kg (very high)
- Glass: 1.0–1.5 kgCO&sub2;e/kg
- PIR insulation: 3–7 kgCO&sub2;e/kg
- Mineral wool: 1.0–1.5 kgCO&sub2;e/kg
What Is Embodied Carbon?
Embodied carbon is the total greenhouse gas emissions from extracting, manufacturing, transporting, and installing a building material. It is expressed in kgCO&sub2;e (kilograms of carbon dioxide equivalent).
How to Reduce It
- Use timber frames instead of steel or concrete where possible
- Specify lower-carbon concrete (e.g., GGBS or PFA cement replacements)
- Reuse materials from demolition (reclaimed bricks, steel)
- Choose recycled steel (60–70% lower carbon than virgin steel)
- Specify local materials to reduce transport emissions
Why It Matters
As operational energy improves (better insulation, heat pumps, renewables), embodied carbon becomes a larger proportion of a building’s whole-life carbon footprint. RIBA’s 2030 Climate Challenge targets embodied carbon limits of <500 kgCO&sub2;e/m² for domestic buildings.
Last updated: April 2026. Values are indicative — check EPDs (Environmental Product Declarations) for specific product data. Data sources include the ICE Database (University of Bath).