2. INSULATE YOUR HOME’S HOT-WATER PIPES
The facts: Every foot of bare 1⁄2-in. copper tubing carrying 120°F water around a 70°F home loses 14.1 Btu an hour; 3⁄4-in. tubing loses 19.1 Btu per hour (1 Btu is the amount of energy needed to raise the temperature of 1 lb. of water by 1°F). You can substantially reduce this loss by insulating the hot-water supply lines.
The fix: Pipe insulation comes in 6-ft. strips and is typically fiberglass or foam-based material. Choose the best you can afford; fiberglass or elastomeric foam will save you more than cheaper foam tubing.
Insulation should fit snugly over the tubing to prevent condensation, and all joints and slits should be firmly sealed. Foam pipe insulation is often available with a preglued slit; you can use contact cement to seal butt ends or mitered joints. Some cements require adequate ventilation, so read and follow all instructions. Fiberglass insulation should be handled according to manufacturers’ instructions. (Always wear safety glasses when working with fiberglass.) Costs range from under $2 per 6-ft. length for R-2 insulation to $12 per length for R-8 UV-resistant Armaflex, used to insulate exterior piping in solar systems.
In a retrofit, the amount of piping accessible for insulating depends on the home’s style. The main distribution lines in most houses are accessible through the basement; only the risers in the walls can’t be accessed. In one-story homes, then, this means you can insulate all but a few final feet of piping.