Insulate Your Water Heater

Task: Install an insulating blanket on your water heater. Set the thermostat to 120 degrees.

Although water heaters are insulated, they can lose heat and waste energy if located in an unheated space, or designed with minimal insulation. If your water heater feels warm to the touch, you will save money and have more hot water by adding more insulation.

Advanced: To save more energy on water heating, consider solar water heaters, tankless, and geothermal pre-heating options. Note that some people limit their hot water use to certain hours of the day, and turn it off completely for the rest of the day and night.

How to insulate your water heater


Water heater blanket kits are available for gas or electric water heaters which are non-allergenic (no fiberglass), and can stop up to 97% of radiant heat loss.

You can also make your own water heater blanket which can be thicker and cost even less to install. Here’s how:

• Use “faced” fiberglass insulation (one side is papered over) to keep the fiberglass particles out of the air. Cut strips of insulation 3” longer than the circumference of the heater. Wrap them horizontally around the heater and seal with vinyl duct tape.

• Using a razor knife, cut away around thermostat controls, drain faucets and vents.

• If your heater is gas powered, do not cover the burner access. Leave three inches of exposed area around the flue collar.

• If you have an electric heater, cut a circle of insulation and fit it over the top, cutting slits for the pipes to go through. Seal any exposed fiberglass with duct tape.

• Covering up labels on water heaters may, in some cases, void warranties. Be sure to read labels to see if this condition applies.

For more information on insulating water heaters, see the US Department of Energy website.

What else you can do:

• Cut back on hot water use by limiting showers to 5 minutes, washing laundry in cold or warm water, and washing dishes efficiently.

“Water heating savings are among the cheapest, easiest, and most cost-effective to implement. Simple stuff such as adding an insulating wrap around water heater storage tanks, and installing great new energy- and water-saving showerheads and faucet aerators all have simple paybacks shorter than three years (less than two years as a package of measures), guaranteeing that bill-savings stay in your pocket for several years thereafter.”Rocky Mountain Institute, Cool Citizens: Household Solutions

Lower settings on water heater:

Most water heaters are factory pre-set at 140 degrees. This may be more than you need, especially in a one or two person household. If your hot water supply is adequate, try lowering the thermostat to 120 degrees. Experiment within the 120-140 range to find the lowest setting which supplies you with enough hot water. Every degree you reduce will save energy costs and reduce pollution.

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