A composition and method for forming a composite material comprising a mixture of component A and component B, component A comprising gypsum and an inhibitor; and component B comprising an accelerator, wherein at least one of component A and component B further comprises a polymer binder having a T.sub.g of below -23.degree. C. or wherein the Shore D hardness of the composite material when cured is less than 70; the method comprising providing a first slurry mixture of component A and a second slurry mixture of component B and blending the first slurry mixture and the second slurry mixture to form a soft composite using a weight ratio of from 10:1 to 1:2.