Pavers That Use Low-Carbon Cement

Concrete is one of our most versatile building materials—and one of our worst carbon polluters. Manufacturing the main ingredient, ordinary Portland cement (OPC), accounts for approximately 5­%–8% of anthropogenic CO2. With carbon in our atmosphere reaching critical levels, we need to find cement alternatives, and fast. There are few commercially available substitutes for OPC, but Solidia is out to change that with a low-carbon concrete mix that is being used for the first time in a commercially available product: EP Henry’s ECO Bristol Stone permeable pavers.

Solidia: a different cement

First a quick cement lesson. OPC is made in high-temperature kilns where limestone (calcium carbonate) is transformed into carbon dioxide and lime (calcium oxide) through a reaction called calcination. This release of CO2 accounts for the majority of cement’s large carbon footprint. As the kiln temperatures climb to more than 1,450ºC (2,642ºF), the raw materials become clinker, which then cools and is processed into cement.