Q: As part of the gut remodel of a 1940 house near Houston, Texas, we installed 3/4-inch rigid foam over the exterior wall sheathing, followed by vinyl siding. On the interior, we exposed the 2x4 studs and installed fiberglass batts. Then we installed 1/2-inch foil-faced rigid foam followed by drywall. In that climate, will these “foam sandwich” walls trap moisture?
Q: I’m considering installing wood siding over a rain screen, but I’m unsure whether the potential benefits justify the extra expense. What is the real benefit of an air space behind wood siding?