The addition of foam agent provides tremendous effects on density, thermal conductivity, flexural and compressive strength. All of these properties rapidly decrease with the increase of foam agent addition from 0 to 5wt% which is mainly attributed to generation of high porosity in the sample matrix with foam agent addition. The decrease of density tends to reduce the load of composite materials and the decline of thermal conductivity can reduce the heat loss and improve the efficiency of heat preservation and energy conservation.

The density, thermal conductivity, flexural and compressive strength of lightweight thermal insulation concrete decreases when content of foaming agent becomes more and more which was chiefly attributed to existence of high porosity in the specimens with foam agent addition by decomposition of foam agent.