Installing Rigid Foam Insulation Under Siding

  • 4-40 hours
  • Intermediate
  • 500-2,500
What You'll Need
Rigid Foam Insulation
Measuring Tape
Dust Mask
Staple or Nail Gun
Electric Screwdriver
Hand Saw

Rigid foam insulation is one of the most important and efficient forms of insulation. It is designed to prevent a house from losing heat. Heating costs increase every year, making insulation more and more important. Although rigid foam insulation is more expensive than fiberglass insulation, it is more efficient. Rigid foam insulation is ideal for use in areas that do not have much space available. This means that it's possible to install a lot of insulation in a very small area.

Step 1 - Measuring up

The first thing that you need to do is measure the walls of your home to estimate how much insulation you will need to purchase. It will be difficult to say exactly how much insulation will be required. You will need to estimate the area you need. Measure the area of all the walls on your home and then work out how much insulation you will need. Be sure to allow extra insulation, just in case you waste any by cutting it wrongly.

Step 2 - Marking Sheets

Use the measuring tape again to work out the sizes of rigid foam insulation boards that you need to fill the wall with insulation. This will need to be designed so that the joints are staggered for durability. Mark the dimensions of the sheets using a pencil so that they can be cut accurately.

Step 3 - Cutting Insulation

Rigid foam insulation is very easy to work with because it comes in small easy to handle sheets. Before cutting insulation, you must wear a dust mask to prevent inhaling any dust. These sheets of insulation can be cut easily by using a table saw or a utility knife. Once the insulation is cut to the right size place it up against the walls to ensure that it will fit properly.

Step 4 - Fixing the Insulation

The insulation should be placed against the wall in between the studs and then fixed to the studs using the staple gun. This will ensure that the insulation cannot move.

Step 5 - Cutting and Fixing Plywood

Next, plywood needs to be fixed over the top of the insulation so that it is hidden from view. The plywood used should be marine or exterior grade to prevent it from becoming damaged when it gets wet. Mark the sizes of the plywood with a pencil and then cut it using a table saw, or hand saw.

Once the plywood has been cut to the right size, it can then be attached to the studs in the wall by using screws, although a normal screwdriver will do a sufficient job, an electric screwdriver is often much easier because there are hundreds of screws to put in on large walls.

Step 6 - Finishing Touches

Once the plywood is installed it's then time to install the siding over the top, you can choose to use either vinyl or aluminum siding depending on the age, style and look of your building. The siding and insulation offer a well insulated home.