Insulation retains heat in winter and cold in summer. Because concrete block walls are porous, hot and cool air as well as moisture travel right through them. By insulating your concrete block walls, you can better control temperature and create a drier environment for your home. Start by adding a vapour barrier and furring strips (thin strips of wood) onto the concrete blocks to hold the insulation.
Create a vapour barrier. Place concrete seam tape over each crack and seam of the block wall. This will reduce the moisture coming through the wall.
Frame the wall by installing furring strips. Install the header and footer of the frame by measuring and cutting the furring strips the length of the wall. Attach the strips using Tapcon anchors and a drill, or use concrete nails and a hammer. Measure the space between the installed header and footer and cut the vertical strips. Each end of the wall should have a furring strip.
Install the batt insulation (precut panels) between the vertical furring strips. The paper backing should face the concrete. Place the rolled insulation inside each column of furring strips. Staple the top and edges using a hammer stapler. Cut any excess insulation using a utility knife.
Rigid foam insulation may be used in place of rolled batt insulation. Attach it to the concrete using strong adhesive glue like Liquid Nails. Insulating concrete blocks this way works best during the framing stage of construction.