This research examines the environmental parameters associated with the production and delivery of building materials in the U.K. in 1991. Using primary data supplied from commercial sources, an eco-profile is produced for each material by calculating the gross inputs of energy and raw materials and gross outputs of solid waste, air and water emissions. The production sequences are traced from raw materials in the ground through to the final product and extend to include transport operations and the production and delivery of fuels and ancillary materials. The results are used to complete eco-profiles for the construction of a three bedroom bungalow house and a four bedroom two storey detached house. It is shown that per square metre of floor space, the construction of the two storey detached house produces considerable reductions in the burdens on the enviromnent. Eco-profiles are used to compare the environmental burdens associated with alternative building materials. The effect of alternative building materials on the eco-profiles of house construction is discussed. It is shown that significant reductions in the gross inputs and outputs maybe made by substituting dense concrete blocks for clay bricks.