Have you seen these?

I guess I'm behind the times, but I didn't know about these little things until we had an energy audit done by the gas company recently. They are little foam pads that you place inside the outlets on your exterior walls to insulate them. I just purchased a pack of 6 for $1.97 at Lowes. The energy auditor said they would pay for themselves in no time with energy savings. Find them with the weather striping and insulating supplies at your hardware store. They also have them to fit light switch plates.

The exterior walls of your home should be completely filled with insulation, but the outlet box itself takes up most of the wall space leaving very little insulation between it and the outside wall. Also, if you have sheet insulation instead of blow-in insulation in the exterior walls it's very likely the installer didn't get the little spaces around the outlet filled in very well. On a cold day feel the outlet cover and then the wall beside it. If there is even a little difference in the temperature you are loosing heat (or air conditioning) through the outlet. On the day we had our energy audit, despite the fact we have nice blown-in insulation in the walls, there was nearly a 10 degree difference in the temperature of the outlet and the wall right next to it. All these little "holes in the envelope" suck the warmth right out of your home through conductivity even if they aren't drafty. Most rooms have at least one outlet on every exterior wall. Some of my rooms have several.

These inexpensive foam pads can help quite a bit and only take a minute to install. Who doesn't want to save money on their heating and cooling bills for years to come?

Just remove the outlet cover with a regular screw driver, place the foam pad inside and replace the cover. You will normally just install these in exterior walls unless you know that wiring for interior wall outlets goes through an uninsulated attic space (through a garage or above attic insulation) which can conduct heat or cold temps through the conduits to your outlet.

While you are at it, be sure and check the insulation on your attic hatch. You can loose 10% of heat in your home through a non (or poorly) insulated attic hatch. That's a lot of money and it's an easy fix anyone can make for $5-10.