Exterior walls, the roof, and the basement/crawlspace comprise the Building Envelope. Proper insulation is critical for controlling the interior environment including heating and cooling efficiency, indoor air quality and moisture control. In addition, a properly insulated envelope can help to prevent a variety of building maladies ranging from water damage due to ice damming to drywall cracking from structural racking. Take a look at the categories on the left to see how correct building envelope insulation benefits the structure for its entire lifespan.