Tape a thermometer on the wall next to the furnace thermostat to check its accuracy.
QUESTION: My house could probably be more energy efficient, but I’m not sure where to start. How can I make some changes that will lower my energy costs?
ANSWER: The older your house is, the more likely you can significantly reduce your utility bills with a few energy-efficient improvements. A simple, do-it-yourself home energy evaluation can help you locate trouble spots and figure out where to make adjustments.
Start in areas with symptoms of existing problems, such as condensation or drafts. Check around window and door frames for leaky gaps and joints. Accidental air leakage accounts for about a third of the energy used for home heating and cooling, according to the Environmental Protection Agency.
Look for leaks around electrical outlets, switch plates, baseboards, fireplace dampers, attic hatches, plumbing, wiring and air conditioners. Air leaks indicate places to seal gaps with caulk or weather stripping. To identify the leaky spots, hold a lighted stick of incense near walls, windows and doors and observe the smoke trail (you can also use a damp hand to feel for drafts).
Check for gaps where the walls rest on the top of the foundation, called the sill, as well as at exterior corners, around the chimney, and at any areas where siding and brick meet. Look for openings around electrical and gas service entrances, cable TV and phone lines, outdoor faucets and dryer vents. Anywhere two different building materials come together; there may be openings where air can escape. Plug cracks or holes with a sealant appropriate to that area.
Make sure doors and windows close properly. Shut the door or window on a piece of paper, then pull the paper out. If it tears, the fit is tight; if not, you’re losing energy.
Older homes often have inadequate insulation, allowing for significant heat loss (or gain during summer). Attics, crawl spaces and basements are prime candidates for air leaks and may call for weather stripping, additional insulation or vapor barriers in problem areas. The U.S. Department of Energy website offers tips for how you can add insulation to an existing home.
A good way to check for specific hot and cold wall areas, indicating air leaks or lack of insulation, is to purchase a thermal leak detector for under $40. Using infrared technology, these devices pinpoint cold and warm on walls and around windows.
You can also check the accuracy of your central furnace or air conditioner thermostat by taping a bulb thermometer next to it on the wall. You may find the thermostat is inaccurate and you’re actually keeping the house warmer or cooler than you think.
Make sure your heating and cooling equipment is in good working order. Look for dirt streaks on the ductwork that indicate air leakage, especially near seams, and seal those with duct mastic. If your unit is more than 15 years old, replacing it with a newer, more energy-efficient model will help reduce energy consumption.
If you prefer to consult a trained energy expert, ask your local electric cooperative if it offers comprehensive home energy audits. HVAC contractors trained to Building Performance Institute (BPI) or Home Energy Rating System (HERS) standards can also perform audits, usually at a cost of $250 to $300.
Send questions to Energy Q&A.