How to Install Rigid Insulation on Cement Blocks

Clean the dust and debris from the cement blocks with a stiff-bristled brush.

Measure the height of the wall. Cut the first rigid foamboard to the measurement using the utility knife and straight edge.

Apply foamboard adhesive to the rigid board. Place the board on the wall, and firmly press the board against the wall to ensure a snug adhesion. Continue this procedure until all the boards are glued to the walls.

Install the first furring strips in the least conspicuous corner. Measure the perimeter along the top of the first cement block wall. Cut furring strips to your measurements.

Place the first furring strip at the top of the wall, horizontally, just under the floor joists. Using a drill with a masonry drill bit, drill a hole into the furring strip and through the rigid board and into the cement block beneath.

Insert a masonry nail into the first hole and tap the nail with the hammer until the nail head is flush with the furring strip.

Continue to drill additional holes every 12 to 15 inches apart, nailing masonry nails into the holes as you go along.

Continue measuring, cutting, drilling and nailing additional furring strips along the entire top perimeter of the cement block walls.

Repeat the procedure to add furring strips horizontally along the bottom perimeter of the walls.

Measure the vertical space between the top horizontal furring strip and bottom horizontal furring strip. Cut a furring strip to length. Install the strip into place.

Continue installing vertical furring strips spaced 16 inches apart, measuring from the center of one furring strip to the center of the next furring strip. This is called measuring "16 inches on center." Because most drywall and paneling is manufactured in 4-foot-wide panels, placing furring strips apart 16 inches on center will simplify the future job of installing walls to the framing.