Q - We have a large sliding glass door to our patio. It always seems drafty by that door, even though we have tried to carefully weatherstrip it. What else should we try? W.C.

A - A large sliding glass door is a large energy consumer both in the winter and summer. This is due to the large amount of sliding and mating edges that must be sealed and the large glass surface area.The majority, but not all, of the draft is from outdoor air leaking indoors. Although these leaks make you chilly in the winter, they rob you of a lot of your energy dollars in the summer. Often, because the cool air from your air conditioner tends to drop down near the floor, you aren't as aware of the leaks as in the winter.

Some of the chilly drafts are not actually caused by air leaks at all. The warm room air near the large glass window tends to get cold, even with thermal glass. This cold air is heavier than the rest of the heated room air, so it sinks to the floor and causes an apparent cool draft from outdoors.

You should also carefully caulk and weatherstrip the rest of your windows and doors. Any air that leaks in through your sliding glass door must push air out somewhere else from your house. Otherwise your house would explode. By tightening up the rest of your house, you may find that it feels less drafty near your sliding glass door.

Blocking the direct force of the wind from blowing against your sliding glass door helps considerably. The amount of cold outdoor air leaking in through a just a small unsealed spot can be increased several times by the wind blowing against the door.

One of the easiest ways to block the wind is to build a covered windbreak around your door. It is basically a 3-foot-wide framed wall on each side of your door, covered with a shingled roof. It can be attractive and provide additional privacy too. Your increased comfort and utility bills savings should justify the minimal material costs.

In the summer, in addition to blocking the wind, the roof acts like an awning to block the hot sun. It also provides an excellent location to hang plants under the roof. If you rely on natural ventilation or fans for cooling, you can either remove it in the summer or build a hinged shutter or window in the side that faces the prevailing summer breezes.

You can write to me for UTILITY BILLS UPDATE No. 169 showing do-it-yourself instructions and a diagram for making a wind and sun shelter for a sliding glass door. Write to James Dulley, The Deseret News, 6906 Royal Green Dr., Cincinnati, Ohio 45244. Please include $1.00 and a self-addressed envelope.

Q - I have a gas clothes dryer and I wondered if I could vent it indoors without causing a problem? L.M.

Comment on this story

A - Although the products of complete gas combustion are basically carbon dioxide and water, you should check your local codes first. Indoor venting of any type of gas appliance often violates codes. Also, your dryer owner's manual may comment on indoor venting. Altering the type of venting designed by the dryer manufacturer may void its warranty.

Venting a dryer indoors may exacerbate any excess indoor moisture problem you may now have. You should keep the lint filter clean and periodically check the vent duct too. It can gradually over time become clogged with lint. This blockage can impede adequate air flow for energy-efficient drying.