Use this formula to calculate your home's energy efficiency

Q. I want to make my house more energy efficient. I am not sure what improvements it needs and I don't want to invest in a professional energy audit. What do I need and how can I do my own energy audit?

A. Most houses, unless they are very new, can benefit from energy improvements. The older your house is, the more likely you can significantly reduce your utility bills from their current level. Compared to the return on most other forms of investments today, energy improvements to your home can provide a very good financial return.

The first step is to do a quick simple analysis to determine how energy efficient your house currently is. This involves totaling up all the energy your house uses throughout the entire year. This total energy amount divided by the square footage of the living area and adjusted for your climate conditions is a good rough estimate of the overall efficiency.

Check your utility bills or other receipts for the amount of energy used. To convert the amounts into the quantity of Btu you consumed, use the following conversion factors: 1 kilowatt-hour of electricity - 3,414 Btu; 1 cubic foot of natural gas - 1,025 Btu; 1 gallon of propane - 91,000 Btu; 1 gallon of oil - 138,700 Btu; and 1 cord of wood - 19 million Btu.

Once you have the total annual Btu amount, divide this by the sum of the cooling and heating degree days for your climate. Next divide this by the square footage of your house. The calculation results for most houses fall into the 10 to 20 range, meaning energy improvements are possible. If it is greater than 20, your house is very inefficient. Less than 10 means significant improvements will be difficult to achieve.

Every house is different, but air leakage typically accounts for 35 percent of energy consumption. Check the windows and doors for leaky gaps and joints. Also check for gaps where the walls rest on the top of the foundation. Heat loss (or gain during summer) through the walls and ceiling account for about another 30 percent.

Holding a lighted stick of incense near the walls, windows and doors and observing the smoke trail can identify leaky spots. Black & Decker now offers a low-cost Thermal Leak Detector (www.blackanddecker.com, (800) 555-1212) for homeowners. It uses infrared technology, similar to professional models, to sense cold and warm areas on walls, windows, etc. The sensor beam turns red on hot spots and blue on cold spots.

Check the accuracy of your central furnace/air conditioner thermostat by taping a bulb thermostat next to it on the wall. You may find the thermostat is inaccurate and you are actually keeping your house warmer than you think. This can greatly increase your heating bills.

Oregon Scientific, (800) 853-8883, www2.oregonscientific.com, offers a solar-powered central digital thermometer with two remote sensors. This allows you to monitor the temperatures and humidity levels in three rooms. It also remotely picks up the local weather forecast and displays it.

Q. I have heard of vampire electricity used by appliances and for cell phone chargers even when they are turned off. What is the best method to reduce this vampire electricity waste?

A. Electronic equipment and appliances do continue to use a little electricity for the controls and to maintain settings when they are turned off. The only way to totally stop it is to unplug the appliances.

Much electricity is consumed by chargers for an array of electronic gadgets and phones. Always unplug them when the item is charged. You can feel how warm they stay even when the phone is disconnected, indicating they are still using electricity.

• Write to James Dulley at 6906 Royalgreen Drive, Cincinnati, OH 45244, or visit dulley.com.