Buildings constructed from concrete cinder blocks offer long-term strength and durability against weather, wind, fire and pests. Regrettably, concrete cubes also provide hardly any natural thermal resistance. With insulation, cinder block walls enable unwanted cold air from the outside to go into your home, particularly in the basement. Add insulation to your cellar walls to improve energy efficiency, decrease heating and cooling expenses, and improve the comfort of your home.
Visit the Department of Energy site to find out how much insulation you need. Most homes need thermal resistance of R-13 on outside basement walls, though houses in the coldest areas of the country could gains from around R-21. Your uninsulated concrete cubes offer just about R-1 or R-2, therefore subtract this from the R-value you’re trying to achieve prior to buying insulation.
Install 2-by-2 wooden furring strips along the length of the cinder block wall. Set the strips perpendicular to the floor every 16 inches and secure them to the block utilizing masonry or concrete screws.
Cut your foam insulation to match between the furring strips. Keep the foam panels tightly to the edge of each strip to minimize air leaks. Cut your foam boards using a utility knife.
Put a double layer of foam board involving each furring strip. Two layers of foam offer an R-value between 8 and 16. Together with the insulation already provided by your block wall, you’ll achieve roughly the R-value advocated by the Department of Energy. In very cold climate zones, then you may need to use 3-inch furring strips to match one extra layer of insulation inside the wall cavity.
Use extra masonry screws to anchor the foam board to the wall every 6 to 8 inches. Choose screws to pass through both layers of foam and into the wall. Think about purchasing specialty foam board anchors designed for this type of program to make the job simpler.
Put in a coating of any typical vapor barrier across the whole wall. Overlap the seams by 6 inches and use nails or screws to secure the vapor barrier to the furring strips.
Insert a layer of 1/2-inch drywall to complete the basement walls. Even if you’re delighted with your unfinished basement, most building codes require foam insulation to be covered with 1/2-inch shingles to improve fire resistance.