Q: How much can I save by covering electric outlets and sealing holes in walls around outdoor faucets and wiring?
A: Sealing these holes is fine to do. It will cut down on drafts, make your house more comfortable and probably save a bit on your energy bills. However, for most homes in a mild climate like North Carolina, you can generally expect modest results from this measure and covering outlets. A study in Texas claimed to “prove” that installing foam outlet covers reduced heating and cooling costs by more than 25 percent. Unfortunately, several other studies have been conducted to verify the first one, and the savings are much lower.
Any air that is getting into or out of your house around the electric boxes is getting in somewhere else first. Usually, it’s coming in around the holes at the top or bottom of the wall where the wires go through. If your house was built in the last 10-15 years, it’s likely that those holes are sealed because it is a fire code requirement that has been actively enforced.
If your house is older than that, it is likely that those holes were not sealed. Going up in the attic and down into the crawl space or basement to seal them will be more valuable than applying foam gaskets, but it is more work.
Sealing air leaks can save lots of money, but usually the easy ones to reach are the least important. The holes in the top of the building are the most important, and while you’re there, look for the really big ones—such as open chases for ductwork or plumbing, or around chimneys and dropped ceilings above cabinets, showers or closets.
Search for “attic bypasses,” and you will get a lot of information on where to find these holes and how to cap and seal them. The idea about big savings from small, easy fixes like outlet covers and caulking around windows has been circulating since the 1970s; however, don’t be disappointed if you don’t see big changes on your bill.
There are also businesses that offer these services, and every county has a Low Income Weatherization Program with people trained to diagnose and fix the problems. In some areas, these programs use private contractors who will work directly for homeowners as well.