An energy audit is an assessment of a home, building, or business that measures how much energy is being consumed, any existing problems where energy is lost, and recommendations of things that can be corrected to increase efficiency, thus saving you money over time. This may be done by a professional using infrared cameras and blower doors. An infrared camera measures the surface temperature variations using light from the heat spectrum. This helps pinpoint leaks and places where the need to add insulation is, since warm areas show as white and cooler spots are black.This is the thermographic inspection. It can be done on the exterior or interior of the building. Better results come from the interior scan because a windy day may make it harder to track heat loss on the outside wall. Heat does not always move in a straight line, so it may not be the point of origin for the loss. A thermographic scan may be run with the blower door test being done.
The blower door is a very powerful fan that is attached to the outside door,which pulls out air to lower the pressure inside. It is best to have the calibrated fan used to get an accurate reading of exact spots of unsealed cracks and openings that allow air to come in. Some inspectors may also use a smoke pencil to detect leaks. The furnace must be off during this test. If you have a fireplace, the damper must be closed and all ashes removed to prevent them from blowing around. The blower door test creates in effect 20 mph winds blowing outside the walls of the house. Turn off any fires from the fireplace and stove. Make sure to have all the windows down and outside doors secured during the test. Open all the interior doors in the house except the closet doors.
The enery audit can include a written report of many things such as themostat settings, the last year or two of bills showing the energy consumed, the climate of the area, and the age of the home. This aids in understanding where changes can be made along with the blower door test and the thermographic scan. To schedule an energy audit contact the public utilities companies, they may be able to reccomend a reputable company that can assist you. There may be independant energy services companies that provide these services in the yellow pages. You can get information on these companies from the Better Business Bureau or recomendations from other clients they have serviced. Residential energy auditors are accredited by the Building Performance Institute (BPI) or the Residential Energy Services Network (RESNET).
For related information, publications, and videos go to www.energysavers.gov/your_home/energy_audits/index.cfm/mytopic=11160