How to Insulate Cold Water Pipes

Cold water pipes will likely sweat if they are not properly insulated. When cold water flows through the pipes, it cools them below the dew point of the surrounding air. This causes condensation to form on the outside of the pipes. This condensation will eventually drip down or off the pipes and cause water damage. Insulation prevents this condensation from occurring and likely will save you costly repairs down the road.

Things You'll Need

• Tape measure
• Foam pipe insulation
• Knife

Instructions

1. Measure the outside diameter of the pipe you are insulating. This will ensure you use the proper size insulation.

2. Take a measurement of the length of pipe you are insulating. Cut your insulation at this length with your knife.

3. Spread the insulation at the seam and slide it over the pipe. Pull the covering off the adhesive and push the seam together to secure the insulation.

4. Repeat Steps 1 through 3 for any further pipe until it is entirely insulated.

Tips & Warnings

• To insulate elbows, install the insulation over a straight portion before or after the elbow following the steps above. Grab the insulation and slide it over the elbow while twisting it back and forth. Once entirely over the elbow, orient the seam on the center line of the pipe and elbow.

• To insulate a tee, install the insulation as you would a straight piece of pipe. Keep the seam at the top of the tee. Carve a small notch out of one side of the insulation at the outlet of the tee. This will allow you to press the insulation seam tight together. To insulate the outlet of the tee, cut another piece of insulation at the desired length and carve a "fish mouth" on one end of the insulation. This is a curved cut that starts at the top of the insulation on one end, swoops in about 1 1/2 inches and then comes back out at the bottom of the insulation on the same end. Picture a half circle -- that is what the end should look like when complete. Slide this insulation into place over the tee's outlet and the "fish mouth" will seal over the first piece of insulation.

References

• SDGE: Insulating Water Pipes
• Smock & Schonthaler : How to Install Foam Rubber Pipe Insulation