Preparation

• Before installing insulation it is important to caulk any areas where air is coming or getting out. The most important areas to check are around windows, doors, pipes, vents and electrical outlets. The easiest way to insulate is to use fiberglass insulation. You can buy faced installation with a paper vapor barrier built in or you can install a plastic sheathing vapor barrier on your own after installing unfaced fiberglass insulation. The outside of your house must be protected before you install the insulation. A vapor barrier such as Tyvek house wrap should be installed and covered by some type of siding. It is very important to keep the insulation from getting wet to prevent mold.
  
  

The installation

• The easiest way to insulate most walls is to get precut insulation. It usually comes in standard heights to fill your wall cavities. You will need to pick the correct R value. The R value tells you how much insulation you are getting. The higher the R value the thicker the insulation. Different parts of the country will require different levels of insulation based on average temperatures and building codes. You must have enough space for the insulation because compressing it reduces its effectiveness. In colder areas, 2x6s are often used for studs because they allow for more insulation. You must insulate every exterior wall of your home, as well as your attic. You may also want to insulate some interior walls for soundproofing. Make sure you put insulation on both sides of water pipes on exterior walls to keep the lines from freezing. You should staple faced insulation into place on the wall studs. Sheetrock hangers prefer you staple the insulation on the inside of the studs so the stud faces are clear. In the attic, you can just lay the insulation between the ceiling joists. If you live in a cold area, consider placing a second layer across the joists perpendicular to the first. You will also need to cut some pieces of insulation to fit in odd shaped areas, such as around electrical outlets and other areas that do not get covered. Use a utility knife to cut the insulation on a flat surface with the faced side down.