If the insulation in your home does not meet minimum levels, this could account for a huge amount of your energy loss. If you own an older home, it is likely that your insulation is insufficient, even though it may have met recommendations at the time it was installed. For information on proper levels, please see Home Insulation Buying Guide.
Start your inspection from the top down.
First, make sure the attic hatch closes tightly and is weatherstripped. In the attic, make sure penetrations for pipes, ductwork, and chimneys are sealed with expanding foam caulk and that electrical boxes for any light fixtures below are sealed with a flexible caulk.
Next, check the insulation itself to see if there is a vapor barrier. It could be tar paper, plastic, or kraft paper. If there does not appear to be a vapor barrier, you can replace the insulation or paint the ceiling with vapor barrier paint. A vapor barrier or vapor barrier paint inhibits moisture from passing through the ceiling, thereby preventing moisture damage and retaining the integrity of the insulation.
Last but not least, make sure that the insulation is not blocking air circulation through the attic vents—be sure to check the eaves vents.
To check your walls’ insulation levels, do one wall at a time, turning off the electrical power to any outlets along that wall. Once you are certain the power is off (test the outlets to make sure they are not “hot”), remove a cover plate and look for insulation around the perimeter of the electrical box. If necessary, gently insert a screwdriver inside the wall—see if it’s met with some resistance by insulation in that wall.
To check an unheated basement, look for insulation under the flooring above. If it is a heated basement, check the walls as you did with the upper floor.
NEXT SEE: Calculating Insulation Needs