How to Replace Fiberglass Insulation With Foam Board

Old fiberglass insulation is not difficult to remove.

Insulation for your home comes in a multitude of shapes, sizes and materials. Many homes are insulated with fiberglass insulation, which retains heat but absorbs moisture. This can be a problem in wetter climates. Foam board insulation is more expensive than fiberglass, but its surface repels water. Replacing your old fiberglass insulation with foam board is not complicated, and the project can be completed in a relatively short time if you have a few assistants.

Things You'll Need

• Protective gear
• Assistants
• Pliers
• Trash bags
• Foam board insulation
• Utility knife
• 1/4-inch sheet foam
• Construction adhesive
• Weatherproof caulk

Instructions

Removing the Fiberglass Insulation

1. Put on a paper suit, gloves, goggles and a dust mask to protect yourself from the fiberglass insulation.

2. Pull out any staples holding the insulation's paper covering, using a pair of needle-nose pliers.

3. Remove the insulation from the wall. If it is in batts, it will pull out from between the rafters in single pieces. If it is loose insulation, ball it up as best you can and put it into trash bags.

4. Sweep the area once you have removed all the insulation to collect any dropped fibers.

5. Dispose of the insulation according to the environmental laws in your area.

Installing Foam Board

1. Cut sheets of foam board to fit snugly in the space between rafters. Foam board is fairly soft and can be cut with a sharp utility knife.

2. Cut 2-inch-wide strips of 1/4-inch sheet foam.

3. Glue a strip of 1/4-inch foam along both sides of every rafter, using construction adhesive. These strips will create a small space between the foam board and the wall, preventing moisture from being trapped.

4. Install the cut sheets of foam board between the rafters, pressing them snugly against the spacers.

5. Apply a bead of weatherproof caulk along the edges of the foam sheets to secure them in place.

References

• Owens Corning: How Do You Remove Fiberglass Insulation?
• U.S. Department of Energy: Foam Board Insulation
• YouTube: How to Install Foam Board Insulation; Louisiana Green Corps