A power-station by-product, engineered into a building material.

Fly ash is the fine residue carried up with flue gases when pulverised coal burns in thermal power stations — captured by electrostatic precipitators before it can leave the stack.

At the micron scale its particles are spherical and glassy, so it behaves as a pozzolan: with cement and water it reacts to form the very same binding compounds as cement itself. Used as a partial replacement it raises long-term strength, cuts permeability, lowers the heat of hydration in mass pours, and trims both cost and embodied carbon from every cubic metre placed.

We supply dry-collected fly ash, classified for consistent fineness, with a test certificate against each lot.