If your heating ducts and hot water pipes are located in unheated areas (such as unconditioned attics, crawl spaces and garages), reduce the recurring heat losses by wrapping insulation around the ducts and hot water pipes.

Pipe Insulation
Be sure to cover the first five feet of the hot and cold water pipes leading into the hot water tank. Otherwise, heat is drawn into the cold water pipe and is lost.

Sleeve-type pipe insulation is available at most hardware stores in typical pipe diameters (e.g. 1/2", 3/4"). Insulate the first five feet of hot and cold water pipe. Mitre the joints for a snug fit at 90 degree bends. Use duct tape or special glue to seal sleeve joints and seams. Where pipes have many short bends, a foam tape insulation is easier to install. Be sure to maintain adequate clearance (3" minimum) between the gas water heater flues and the pipe insulation.

Duct Insulation
Fiberglass duct insulation with an "R-value" of 6 or better is recommended. To avoid skin irritation, wear protective clothing such as a dust mask, goggles, cap, loose clothing and gloves. (Take a cold shower to close your pores after working with fiberglass.)

If you are insulating heating ducts only, no vapor barrier is needed on the insulating material. However, if you have air conditioning ducts you will need material with a vapor barrier. Remember to face the barrier outward.

There are some very old ducts in some homes that look similar to corrugated aluminum. These should not be insulated as they may have become brittle and may fall apart.

How much insulation do I need?
Measure the length of your ducts in inches. If you have ducts of different circumferences, then keep track of the total length of duct for each size. To determine the amount of duct wrap you will need, use this chart:

*Multiply the footage factor by the length of your circular duct to get the amount of square footage needed.

Tools needed for installation

• Tape Measure
• Hat to Protect Hair
• Plastic Goggles
• Cotton Work Gloves
• Staple Gun
• Portable Light
• Duct Tape
• Respirator to prevent the inhalation of insulation
• Utility Knife & Extra Blades
• Step Ladder
• Tool Pouch

Q: How do I install the insulation?
A: The installation steps for installing duct wrap are:

1. For round or rectangular ducts start at either end by taping the end of the insulation to the end of the duct. If the material you are using is unfaced, tape may not work well. Wire is an effective substitute.
2. Wrap the insulation in a spiral fashion overlapping each successive layer by 2". If the whole roll won’t pass between the duct and joists or framing, cut the roll into shorter sections. Tape each section end down.
3. Sometimes a duct is nestled between joists so that you cannot wrap around it. In this situation, lay the insulation along the length of the duct and then staple the edges to the joist. Be careful not to crush your insulating material. It is the trapped air in the fiberglass that does the insulation work.