How to Insulate a Concrete Block House

A concrete block house provides a sturdy shell that offers an insulation factor but in climates where more protection is desirable, additional insulation is installed on the interior of the house. In order to provide a suitable cavity for insulation, a sub wall is framed just inside the surface of the concrete block. Once you've created the stud space, you can begin the insulation process. Insulation with an R-value of 13, will provide a finished wall value of approximately R-23, when combined with the existing insulation factor of the concrete blocks.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Dimensional lumber
• Hammer and nails
• Circular saw
• Measuring tape
• Carpenter's level
• Staple hammer
• Insulation bats
• Utility knife
• Respirator
• Long sleeves and long pants

1. Frame an interior stud wall with dimensional lumber if one does not exist. The wall should extend a minimum of 3 1/2-inches into the room. Position structural studs on 16-inch centers on a floor plate and a top plate.

2. Install all mechanical elements before insulating the wall. This includes electrical outlets and switches, heat and air ducting and all plumbing. Insulation is the last element installed in a wall.

3. Measure the interior section of each stud space and cut a piece of insulation batting 1-inch longer. Fit the bat into the stud space and use a utility knife to cut away portions that cover wires or plumbing. The paper side will face you and the raw insulation will face the concrete block wall.

4. Unfold the paper nailing strip on each side of the batting and pull it evenly over the adjacent stud. Staple the paper strip every couple of feet, just enough to hold the batting in place.

5. Check around installed outlet boxes, light boxes or windows to ensure that no large gaps are visible between the element and the insulation. Cut and tuck small bits of insulation into the gaps, if necessary.

Tips & Warnings

• You're ready to hang drywall after the insulation is in place. Contact a carpenter for assistance if you have limited building skills.
• Avoid packing the insulation in tightly. It is designed to offer the best insulation factor when fluffy and lofty. Protect yourself when installing insulation. Most insulation bats contain tiny fiberglass filaments that may damage your lungs if inhaled. In addition, direct skin contact may result in irritation. Wear long sleeves and long pants and use a respirator.

Resources

• Find insulation