Robert writes from South Beloit, Illinois: "I want to insulate my basement walls (concrete block) is it ok to fasten/glue your 2" pink 4x8 sheets directly onto the concrete block or should I leave an air space? Also, our local Menards doesn't seem to have the insulpink product."

Answer: Yes, you can apply PINK foam insulation boards directly onto concrete block. You will need a special non-petroleum-based adhesive that is compatible with Extruded Polystyrene foam insulation. Click on the words Foamular® Rigid Foam Insulation for Basement Walls and you will see instructions for your project, including pictures. As you no doubt know, InsulPink® foam insulation is specifically designed for basement walls. It has channels that allow it to be easily installed with furring strips. Owens Corning sometimes wishes it could control the distribution of its products but the stores decide what products they will stock. Good luck finding InsulPink foam insulation.