Using a pipe insulation kit to add insulation around accessible water pipes will save you energy, lower your heating bills and prevent pipes from freezing during the winter months.
Look for water pipes that pass through spaces where cold drafts are likely, such as crawl spaces, garages and attics. Check the pipe leading directly from the hot water heater and don't ignore hot water lines. Though slower to freeze they are more likely to burst than cold-water lines.
Before insulating, you must measure the length of each section of pipe. Total the lengths for each section and add about 10 percent more for waste. This is how much insulation you will need. Measuring the diameter is a bit more tricky. One way is to take two short boards and place them across each side of the pipe. Adjust the boards until they are parallel to each other, then measure the gap between them. Another method for measuring diameter is to measure the pipe's circumference with a retractable tape measure and divide the number by 3.14 (pi).
Make sure the pipe insulation kit you choose includes adhesive tape or contact cement for sealing. The most common pipe insulation is a tubular foam sleeve slit lengthwise. Tubes without slits are designed for installation over new piping, but they can easily be slit with a sharp utility knife.
Open the pipe insulation along the slit, press it onto the pipe, and seal it with an adhesive tape or contact cement to prevent summertime condensation.
When using adhesive to bond seams, don't insulate pipes while they are hot. Wait 36 hours after sealing the insulation before circulating hot water through the pipes.
After insulating the straight sections of the pipe, you'll need to insulate the valves too. Preformed valve covers are the easiest and most effective option. Simply fit the two halves over the valves and seal the edges with adhesive tape. For hard-to-cover valves, you can use strips of foam or fiberglass designed to wrap around pipes or fittings.
To provide maximum protection for pipes that are very vulnerable to freezing, you can add electrical pipe heating cable. Prior to adding foam insulation, the cable is attached straight along the pipe or wrapped around it. Once it's connected to the power supply, the cable generates just enough heat to keep the water running through your pipes all winter.
If using electrical pipe heating cable, make sure to follow the manufacturer's instructions for safe and proper installation.