Work out embodied carbon of materials instantly with clear inputs, formula shown and shareable results.
Embodied carbon is quantity times a material carbon factor. Ordinary Portland cement concrete runs 250-400 kg CO2e per cubic metre depending on strength and cement content, and reinforcing steel 1.4-2.5 tonnes CO2e per tonne depending on the scrap content of the route. Steel often contributes half the total despite its small mass.
Embodied carbon
Total = concrete volume x concrete factor / 1000 + steel mass x steel factor
Cement replacement with ground granulated blast furnace slag or fly ash, lower strength class where structurally acceptable, and design efficiency that simply uses less concrete. Replacement of 30-50% of cement is routine.
Electric arc furnace steel from scrap has roughly a third to a half the embodied carbon of blast furnace steel from ore. Specifying recycled content or requesting an environmental product declaration captures the difference.