Q
My utility bills seem too high and I was considering having an energy audit done. Are there different types of energy audits available, and which type of energy audit is best? J.E.
A - There are many types and methods of doing energy audits of houses. These can range from a simple do-it-yourself energy checkup to detailed infrared thermography and blower door infiltration tests. In most older houses, the expense of a good energy audit is a worthwhile investment.
The cost for an energy audit can range from no cost for a do-it-yourself checkup to several hundred dollars for a "high-tech" analysis by professionals. There are also "house doctors" who do the audit analysis and make many simple improvements the same day.
Infrared thermography uses a camera with a special heat sensitive (infrared radiation) film. Hot areas appear red on the developed picture and cold areas appear blue. This is an excellent method for detecting voids in wall insulation. Small insulation voids can result in great energy losses.
Although you may have seen infrared pictures of the exterior of a house, the analysis is often done from indoors. Outdoor pictures show the areas of energy loss, but it is of-ten difficult to determine where the actual air leaks are originating from indoors.
A blower door test is used to determine the amount of air leakage in a house and where the air leakage is occurring. A large fan is positioned in a window or a door and it sucks air out of the house.
This negative pressure draws outdoor air in any leaky areas so they are easier to detect. Infrared pictures can be used to indicate the location of the air leaks. Also, smoke guns are helpful to find hidden leaks.
Some blower doors are also calibrated to measure the actual amount of air leakage into your house. It is helpful to know this so you can determine if you need additional mechanical air ventilation for humidity control and acceptable and comfortable indoor air quality.
For a do-it-yourself energy audit, you can turn on all your kitchen and bathroom vent fans to simulate a blower door test. (Be sure to switch off your gas or oil furnace and water heater first.) Near all windows, doors, and other suspected leaky spots, hold a lighted stick of incense, lighted candle, or just dampen the back of your hand to find leaks.
You can write to me for UTILITY BILLS UPDATE No. 085 showing a list of names, addresses, and telephone numbers of 100 infrared ther-mographers throughout the country, and a do-it-yourself home energy audit check list. Write to James Dulley, The Deseret News, 6906 Royal Green Drive, Cincinnati, OH 45244. Please include $1 and a self-addressed STAMPED BUSINESS-SIZE envelope.
Q - I plan to install a rigid clear plastic storm window under my skylight. It will be attached with the magnetic seals. Should I caulk all around the steel mounting strip that is attached to the opening? G.R.
A - From an energy efficiency standpoint, you want to block any indoor air movement from getting between the skylight and the storm window. However, if some condensation does occur during cold weather, the moisture needs a path to escape.
You should caulk all around between the steel mounting strip and the trim of the skylight opening except for two 1-inch lengths at each top and bottom corner. There will not be much air flow through these spots, but they will allow any condensation to gradually escape.
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HEAT LOSS:
Attic & ceiling: 15%
Windows & doors: 26%
Walls: 13%
Basement or slab: 11%
Air leakage: 35%