Adequate insulation is great but it won’t be as effective if air is leaking in from other areas of your home.  You won’t just feel the result of air infiltration; you’ll see it in your heating costs. Air leaks also allow moisture, dust and allergens into your home which can cause health issues for those who are affected by changing air quality.

Common Air Leak

Other than the obvious places like windows and doors, air can get into your home through various spots. According to the best places to check for air leaks on the exterior of your home are:

  • Exterior corners
  • Outdoor water faucets
  • Where the chimney meets the siding
  • Where the foundations meets the brick or siding

For an interior rundown, be sure to check:

  • Electrical outlets
  • Switch plates
  • Electrical and gas service entrances
  • Baseboards
  • Attic hatches
  • Fireplace dampers
  • Wall- or window-mounted air conditioners.
  • Cable TV and phone lines
  • Where dryer vents pass through walls
  • Vents and fans


Thermal Image

Another great tip from to detect air leaks is shine a flashlight at areas of the interior of your home while a friend or spouse looks for the light on the outside.  For windows and doors, shut them on top of a dollar bill and if you can pull out the dollar bill without any resistance, air infiltration is likely.

A more professional way is with an energy audit. These can be done a couple ways, either with the blower door test or thermal imaging scan. The blower test involves a door-panel system with a fan and pressure gauges that create negative pressure which pulls air through the cracks of your home. The thermal imaging test involves scanning the home with a thermal imaging camera and finding where cold air is coming in at.

For the St. Louis area, you can find more information on getting an energy audit here.