Your Home Leaks Energy in a Number of Ways
1. Attic Insulation
Have you checked your attic insulation lately? It is a little-known fact that the attics in many older homes lack insulation in the corners (if they even have attic insulation). It's like having a down jacket with a broken zipper. This insulation is important to insure minimal heat loss via the ceiling. If needed, an auditor may recommend blown-in insulation which covers areas better than rectangular batting because loose insulation gets in the nooks and crannies, and conforms around odd shapes.
Condensation and ice forming on windows is a good indicator of heat loss through windows. Either double-glazed windows (two panes set in one frame) or storm windows will improve single pane windows R factor from R-1 to R-2, a 100% increase. (The R-factor refers to the component's thermal resistance.) This increase equals a 50% decrease in heat lost via the window. (Don't be confused by window manufacturers claims and think it will save that amount on total heat loss. The home still has walls, ceilings, doors, and floors to consider). Caulking gaps around windows and around any loose glass may be suggested to lessen drafts.
3. Drafts and Air Leakage
Besides windows, air can leak out of your home in many other ways. Not only can these bump up your utility bills, but the drafts can make your home miserable. Often it can be very difficult to detect these leakages. Many times, there are hidden air leakage paths in the attic, basement, and even interior walls. Using a blower door to test for drafts may be the only practical way to find the real causes of a drafty home. Light fixtures and electric sockets are another frequent culprit for air leaks. If an auditor feels drafts coming from some of them or detects them with an infrared camera, he may recommend foam sealers specifically made for electric outlets.
Basements can be sucking a lot of warm air from your home and your furnace may not be operating efficiently. There is a lot you can do to help an old system to run more efficiently. Insulation materials with a reflective surface put up on the basement walls, especially around the furnace, bounce heat back into the room instead of letting it escape through the walls into the ground. Sealing loose basement windows helps, but most old furnaces do not have a source of fresh air ducted to them. A window nearest the furnace should be left loose as a necessary source of fresh air. If the basement is too tight, the combustion process inside the furnace will draw fresh oxygen from upstairs, creating drafts and wasting heated air. An auditor can determine if the system is so old that it really must be replaced.
Basements that have crawl spaces often lack a vapor barrier. If it is needed, an auditor recommends laying heavy plastic over the exposed earth of a crawl space. This unheated area below the house, through which the heating ducts often run, not only pulls heat, but since it is warmer than the surrounding earth, acts as a wick to pull moisture from the soil.
5. Household Appliances
Household appliances and fixtures can be a huge drain on your energy bill. Energy Star rated appliances can often reduce energy usage by 40%. An auditor assesses the input/output ratio of appliances to determine if replacements are necessary.