Installing Rigid Foam Insulation Sheathing

Rigid foam insulation is a much better insulator than Fiberglass but it's also much more costly. There's no need to unroll and cut huge sheets of insulation because rigid foam comes in easy-to-handle sizes. Rated at R-4 to R-6.5 per inch of thickness, rigid foam insulation is also an excellent insulator. This is much better than other types of insulation.

It's possible to install rigid foam insulation on interior and exterior walls in your home, it's possible for anyone to install this themselves with very little effort.

Step 1 - Measuring

Measure the size of the walls where insulation is required. Make sure that both the height and width of each space that you will be insulating is measured accurately. You will typically be installing the insulation in between the furring strips. These are the strips of wood which are designed to support the face of the wall. Once you have measured every space mark them down and work out how much rigid foam insulation you need to buy.

Step 2 - Preparation

Ensure that you're never installing foam insulation on damp walls, check that the walls are completely dry before you fit any of the different types of insulation.

Step 3 - Cutting Rigid Foam

Once you know your measurements mark the required size onto a piece of foam insulation. This should be as accurate as possible as it will make the insulation stay in place and also make it much more effective. It's very easy to cut the foam as it can be cut using a saw or knife.

Step 4 - Fitting the Insulation

When the insulation is cut to the right sizes it can be pushed into the wall between the furring strips. Try to make this insulation fit in the wall tightly so that you can improve the chances of it staying where it's supposed to.

Step 5 - Fixing the Insulation

If any of the insulation isn't a tight fit and seems loose, use some glue to hold it into place. The easiest way is to glue the insulation against the foundation wall itself.

Step 6 - Vapor Barrier

Cut a sheet of plastic big enough to cover the whole expanse of insulation and use the staple gun to fix it into place along the furring strips or into the insulation itself. This will form an adequate vapor barrier which is required to protect the finished wall from problems with moisture. Alternatively some foam insulation has insulation attached to the back which will make it easier to install.

Step 7 - Finishing the Wall

Now all that's left to do is fix drywall over the wall as you would normally, then plaster and decorate. There's a good chance that you will never need to worry about this insulation again as it should do its job for many years to come. However, it's worth looking out for signs of insects, especially carpenter ants because these can sometimes be attracted by rigid foam insulation.

Rigid foam insulation is no more difficult to install than fiberglass insulation on a roll, however it is normally slightly more expensive, which means you should take more care when working with it.