Save Energy With Rigid-Foam Insulation

摘要

Like most builders in the Northeast, I've been using rigid-foam insulation for a long time. I've used it to insulate foundation walls and basement slabs, and to meet code-required R-values in cathedral ceilings. Until about five years ago, however, I never used it as part of a wall assembly. Then I worked on a house that required a high R-value in walls built with 2x4 studs on 12-in. centers. The best solution was to add a layer of rigid insulation over the exterior sheathing.