Q.: In the March 1977 issue, page 141, there is a discussion of how to eliminate the pond on a roof by removing the builtup roofing, spraying on a polyurethane foam in a number of passes, applying a skin by flood-coating and then reroofing. The method was said to be useful when ponds can be corrected by application of foam to a 6- or 7-inch depth. Our problem is that we can't find any roofing contractor who is familiar with the technique and is willing to bid this type of work.

A.: The work is done by insulation contractors. The way to find a bidder is to check the telephone yellow pages under "Insulation contractors, cold and heat." Make inquiries among them about who in town is spraying urethane foam insulation.