How to Insulate a Water Heater

Insulating your water heater is one of the simplest and most cost-effective home improvements you can make. It takes about 30 minutes, costs under $30, and can reduce standby heat loss by 25-45% - saving you $20-$45 per year on energy bills. Over the life of your water heater, that adds up significantly.

This guide shows you exactly how to insulate your water heater tank and pipes.

Should You Insulate Your Water Heater?

Insulating is most beneficial if your water heater is in an unheated space like a garage, basement, or utility room that gets cold in winter. It is also worth doing if your tank feels warm to the touch on the outside - that warmth is wasted energy escaping through the tank walls.

Modern water heaters manufactured after 2015 already have improved built-in insulation and may not benefit as much. Check your owner's manual before adding an external blanket.

Do not insulate if:

• Your water heater is a gas unit with a top-mounted flue - the blanket must not cover the top or the flue
• Your owner's manual specifically advises against it
• Your heater already has an energy factor of 0.95 or higher

What You Will Need

• Water heater insulation blanket
• Scissors or utility knife
• Tape measure
• Marker
• Duct tape or the tape included with the blanket

Frost King SP60 Water Heater Insulation Blanket - 3 inch thick, R10 rating, 60 x 90 inches, fits most standard tank water heaters. All-season protection, easy to install.

How to Insulate an Electric Water Heater

Step 1: Turn Off the Heater

Turn off the circuit breaker for the water heater before you start. Safety first.

Step 2: Measure and Cut the Blanket

Measure the circumference and height of your tank. Most insulation blankets are pre-sized to fit standard tanks, but you may need to trim the blanket to fit around pipes, the access panel, and the T&P valve discharge pipe.

Step 3: Wrap the Blanket Around the Tank

Wrap the insulation blanket around the tank, starting at the bottom. Keep the blanket smooth and snug against the tank surface.

Step 4: Mark and Cut Openings

Mark the locations of the access panels, the T&P valve, the drain valve, and any pipes. Cut openings for these with scissors or a utility knife - do not cover them.

Step 5: Secure the Blanket

Use the tape included with the blanket (or duct tape) to secure the edges. Make sure all seams are taped down firmly.

Step 6: Do Not Cover the Top

For electric water heaters, you can cover the top of the tank with a circular piece of insulation cut to fit. This further reduces heat loss from the top of the tank.

Step 7: Restore Power

Turn the circuit breaker back on. Your water heater is now insulated.

How to Insulate a Gas Water Heater

The process is similar to electric, with two important differences:

• Never cover the top of a gas water heater - the flue pipe at the top must remain clear for safe venting of combustion gases
• Never cover the burner access panel at the bottom - the burner needs airflow to operate safely
• Leave at least 2 inches of clearance around the top and bottom of the tank

Follow the same wrapping steps as above, but cut the blanket to stop several inches below the top of the tank and above the burner access area at the bottom.

How to Insulate Hot Water Pipes

Insulating the first 6 feet of hot water pipe coming out of the top of your water heater further reduces heat loss and helps hot water reach your faucets faster.

Use foam pipe insulation sleeves - simply cut to length and snap them around the pipes. This is especially effective for pipes running through unheated spaces.

How Much Can You Save?

The blanket typically pays for itself within the first year.

Tips for Best Results

• Combine tank insulation with pipe insulation for maximum savings
• Set your thermostat to 120 degrees F - insulation works best at the recommended temperature
• Check the blanket annually and replace if it becomes damaged or compressed

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