Sealing drafts increases home comfort year-round, while decreasing the amount you spend to heat or cool your home. During the winter months, for example, if you feel a chill when you plop down in your favorite easy chair, those winds whistling through your house as cold air infiltration can cause 80 percent of a home's heat loss.
In winter it can be too cold to caulk windows and doors from the outside, but there's still a lot you can do to cut down on drafts. With a caulk gun and a little know-how, you can make several money-saving improvements without leaving the comfort of a warm house.
Windy walls: The exterior walls of your home are like Swiss cheese, with each "hole" (for a window, door, outlet or light switch) a source of air leakage. Sealing drafts around these openings from the inside can prevent serious energy loss.
Windows: Caulk the window molding where it meets the wall. Use acrylic-latex caulk because it spreads easily and can be cleaned up with water. A good technique is to squirt a thin bead of caulk at the intersection of the wall and molding, and then use your finger to spread the caulk into the seam. Next, use a sponge and warm water to remove excess caulk and finish spreading the caulk. Don't forget to caulk under the sill as well--this area is particularly leaky and a good seal-up job is important.
If your windows themselves are the source of drafts, consider investing in replacement windows. These are specially made to fit inside your existing window openings and can be installed with very little disturbance to the outside wall and siding. Replacement windows have insulated glass and most tilt in for cleaning. Prices vary, but an average-size window should cost about $150 plus installation. Most large home centers now sell good-quality replacement windows. Purchasing from them generally means you'll get a decent job for a fair price, and have a reliable company to complain to if you're not satisfied.
Doors: Caulk around the inside door molding just like you've done with the windows. In addition, check the weatherstripping around the molding on the exterior side of the door. If the weatherstripping is worn or cracked, replace it. Next, check the door sill at the base of the door. When closed, you should not be able to see light coming through the door. Sills are usually adjustable so if you see any gaps, move the sill to close them. When the sill is properly installed, the door should just rub across it when closed. Don't be too picky about having the door close easily without rubbing the sill. A stiff door will keep the drafts out. Baseboard moldings should also be caulked wherever they meet the walls to seal out air leaks.
Outlets and switches: Wall openings around outlets and switches can also let a blast of cold air into your house. Home centers and electrical supply houses sell special gaskets which keep drafts to a minimum. To install them, remove the outlet or light switch covers. The gaskets, which have openings to fit over the outlet or switches, are then placed between the device and the metal cover plate. Be sure you turn the electricity off before installing gaskets to avoid electric shocks.
When you're done with the walls, don't forget to check your ceilings for openings that need to be sealed as well. For example, just like an exterior door, attic stairs or hatches should be weatherstripped and the back of the stair or hatch should be insulated as much as possible, sealing drafts as you go!