A blower door test will reveal areas where there are cracks, crevices, gaps, etc in the exterior structure of a home that will allow outside air to move through to the inside of the conditioned space of a home. The blower door test will assimilate winds of up to 50 miles an hour blowing against a home. It will be possible to actually feel the wind as it moves through cracks, crevices, gaps, etc. from the outside to the inside of the home.

All of the areas where wind moves into the home from the outside when added together could be equal to having a window or door left wide open.

An infrared scan of a home will reveal areas where there is no insulation or where insulation was improperly applied. Batt insulation when installed properly fits snugly between two wall studs in a wood framed structure. If insulation is not properly installed there will be areas where the R-value of the wall is significantly diminished. The R-value of a wall is determined by the amount of inch depth inside the cavity. A typical 2x4 wall R13 and a 2x6 wall R-19. These may vary by year built and can only be confirmed by actual site. Look around for wall penetrations and probe with a plastic knitting needle. Some old 2x4 walls only have R3 or less.


It is probably best to first learn where the air leaks in your home are so you can close them up. Air leaks would contribute to approximately 30-40% of you loss. Other big wasters are fireplaces, skylights, and un-insulated areas. The rest go through windows and doors. Low levels of insulation are also a factor. The energy efficiency of a home will be vastly improved by properly closing the cracks, crevices, gaps that allow air to pass directly into a home's conditioned space through the exterior of the structure.

Your biggest bang for your buck begins with the blower door test.