Basement and Crawl Space Insulation, in addition to air sealing and controlling moisture will save energy and increase your home's comfort. Basements can account for 20 to 35 percent of a home’s total heat loss. When you are preparing to insulate these areas there are few things to consider before you begin such as ventilation. For the proper application process refer to Natural Resources Canada, Keeping the Heat In publication. It's available online or you can order a free copy by calling 1-800-387-2000.