Your attic is the most important place in your home for insulation. Because heat rises, a large quantity of hot air will find its way into your attic during the winter months. If your attic is not completely insulated, this heat will leak outside, causing the average temperature of your home to drop and forcing your heating system to work even harder to maintain a stable level of heat within your home. Thankfully, completely insulating your attic is a fairly simple process that requires only some basic tools and materials.

Locating Leaks

Most leaks in your attic will occur around electrical fixtures or other installations that go through your roof. Check around any features within your attic, such as pipes, flues, electrical wiring, air conditioning, ducts, and other similar installations for any exposed gaps. The actual size of the gap will determine how the leak should be properly insulated.

Small Leaks

Smaller leaks, which as a general rule should be smaller than your thumbnail, can be properly sealed simply using a caulking gun and a tube of caulk. Using silicone caulk is the best choice, as silicone caulking provides the best water resistance and can hold up to changes in temperature much better than alternative types of caulking can. Simply squeeze a small bead of caulking along the gap in question, and use your finger or a popsicle stick to smooth the caulk out and ensure a tight seal.

Big Leaks

For gaps that are larger than your thumbnail, you should make use of polyurethane foam. It comes in a spray can, and expands rapidly as applied, providing a secure and large seal around gaps in your insulation. Polyurethane foam can be found in most hardware stores. Simply use the spray can and straw applicator to apply the foam to the gaps in question, allowing the foam to expand normally. Once the foam is in place, let it sit for at least an hour (check the can for exact hardening times) without touching it.

Chimneys and Hatches

For chimney flues and access hatches into your attic, foam and caulking doesn't work as well. Instead, you should use metal or plastic flashing, which provides a solid seal against air flow. Self-adhesive flashing can be found at most hardware stores and can be easily installed by simply pressing them into place around the flue or access hatch in question. Ensure that there is no space between the flashing and the hatch or flue to provide the best seal possible.