When heating bills are higher than expected and a home begins to feel drafty, many homeowners blame their insulation or their furnace. While upgrading to a high-efficiency furnace or adding more insulation to the attic may help eliminate drafts and reduce your energy bills, there is another culprit to consider -- your windows. Leaky windows let cold air flow into your home at an alarming rate, forcing your furnace to work harder to keep the temperature up. Even with the heat on full-blast, you'll feel a chill every once in a while when the cold air blows in your direction.

Sources of Heat Loss Through Windows

There are two main ways in which heat is lost through windows. First, heat is lost directly through the glass panels. The glass becomes chilled through contact with the cold outside air, and then sucks heat out of your home's interior. Second, heat is lost through gaps around windows frames, which allow cold air to directly enter your home. Older windows tend to cause greater heat loss than newer ones, both because they tend to be less tightly sealed, and because they are typically made with thinner glass, through which heat passes more easily.

To determine whether your windows are to blame for your high energy bills, simply take a moment to examine them. Look at the glass panes. Are they secure, or do they wobble a little when you press on them? Loose glass is a sign that your windows are aging and are probably letting in the cold. On a windy day, place your hand in front of the space where the window meets the window frame. If you feel a chilly breeze, your windows are leaky.

Replacing Your Windows

If your windows are old and leaky, the most effective way to reduce your energy costs and keep your home warmer is to replace them with new, energy-efficient windows. In time, energy-efficient windows will likely pay for themselves through lower heating and cooling costs. The most efficient windows consist of two panes of glass with gas between then to minimize heat transfer. Solar coating helps them absorb heat from sunlight. Of course, if you cannot afford these features, replacing your old windows with even basic, well-sealed, new windows made from thicker glass is better than nothing.

Quick-Fixes For Existing Windows

Replacing your old windows can be quite costly. If this is not an option for you, there are several quick fixes that you can use to decrease heat loss through your existing windows. Start by using weather stripping to seal the gaps between your windows and the window frames. This will keep cold air from blowing inside. Small gaps can also be filled with caulk.

To prevent heat loss through the glass panes, you can place insulating plastic sheets over your windows. Available for just a few dollars apiece at most hardware stores, these plastic sheets adhere to your windows' surfaces. Follow the directions on the package to apply them -- you don't need any construction or home improvement experience to do so.

Insulating curtains, made from thick material such as canvas or wool, can also help reduce heat loss through your windows for homes. They'll help keep cool air that blows in through cracks and crevices from flowing into the room. Make sure you choose long curtains that extend all of the way to the floor to block drafts as effectively as possible.

When your heating bills are higher than desired, it's important to consider whether your windows may be to blame. Heat loss through poor windows can be quite substantial, and even a simple improvement, such as applying caulk to gaps between the window and window frame, will help make your home more comfortable and your heating bill more affordable.