Can foam insulation be glued to foundation walls?
Chris writes from Brockton, Massachusetts: “I have a 6″ waste pipe running around the perimeter of my basement walls. I will be using 2×4 studs and frame away from the foundation wall to allow clearance for the pipe. 1) Can 3/4″ Foamular 250 be glued to the foundation walls to be used as a vapor barrier? The basement is dry. 2) There would be an air gap between the XPS and the studs. I would use unfaced insulation bats between the studs. Is this air gap acceptable?” Answer: You can use FOAMULAR® insulation on the basement walls. Be sure to use an adhesive that states it is extruded polystyrene safe. FOAMULAR insulation at 3/4 inch is not considered a vapor retarder even though it will slow the travel of moisture. The air gap will be just fine. Something you may want to take into consideration though: The pipe will have less heat getting to it and will increase the chances of it freezing. You may want to insulate the pipe also.
