Best Water Heater Blankets of 2021

Save on energy bills and keep your water heater cozy with one of these top blankets.

Your water heater is working even when you aren’t home and using valuable energy to stay heated.

To help your water heater stay heated during the colder months of the year, a blanket could do the job. But not just any blanket — a water heater blanket is specialized in insulating your heater from the outside.

We’ve reviewed and compared five of the best water heater blankets based on material, size, ease of installment, and insulation ability.

Our Top Picks

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Product Comparison Table

Product Image of the SmartSHIELD -3mm 24'x50Ft Reflective Insulation roll, Foam Core Radiant Barrier, Thermal Insulation Shield, Commercial Grade (24'x50')
Best for Multiple Uses
Reflective Insulation Shield
  • Double layered foil
  • Vapor barrier
  • Great for indoors & outdoors
Product Image of the Water Heater Blanket Insulation, 'NON FIBERGLASS', Fits up to 80 Gallons, Energy Star Certified,
Best Material
SmartJacket Water Heater Blanket
  • Fits a range of sizes
  • Easy installment
  • Instructions & tape included
Product Image of the Frost King SP60 All Season Water Heater Insulation Blanket, 3” Thick x 60” x 90”, R10, Silver
Best All-Season Insulation
Frost King Water Heater Blanket
  • For all types of water heaters
  • Thick fiberglass insulation
  • Safe from water & mold damage
Product Image of the US Energy NASATECH 'Non Fiberglass' Up to 80 Gallon Water Heater Insulation Jacket Kit (42sqft) (Made in the USA) Includes: Reflective Foam Core Insulation & Aluminum Foil Seam Tape
Best Lightweight Insulator
US Energy Products Insulation
  • Free of toxic materials
  • Thin & lightweight
  • R-value of 7.2
Best Fire Resistance
Reflective Foil Waterr Heater Blanket
  • Safe, non-toxic materials
  • Plenty of material
  • Kit includes everything you need

What Is a Water Heater Blanket?

A water heater blanket, or insulation blanket, is made to wrap around your water heater to provide extra insulation when needed.

This prevents the water heater from losing heat and helps it to stay at a consistent temperature. If the heater isn’t well insulated, it will lose heat even when you don’t use any hot water. The heater will then use more energy to get the temperature back up, resulting in a higher energy bill.

Save Your Money

Insulating your water heater with a water heater blanket could save you anywhere from 7 to 16 percent on your annual energy bill. Additionally, it may reduce your standby heat loss by 25 to 45 percent (1).

The blanket’s material depends on the manufacturer — it could be anything from fiberglass and foil to cotton.

Insulation is usually rated by its “R-value” which measures its thermal resistance. Therefore, the higher the value, the more insulation it will provide (2).

The R-value of the blanket is affected by factors such as:

  • Material.
  • Thickness.
  • Density.

Which one you should choose depends solely on how much insulation your heater needs, if any. In fact, some water heaters simply do not require additional insulation (3).

Do I Need a Water Heater Blanket?

The first thing to consider is the age of your heater. Older heaters most likely will need extra insulation, especially during the winter. New water heaters are most often already insulated.

Check User Manual

If you do have a new water heater, make sure to check the user manual. It might say you should not insulate the heater on the outside. It might also be marked on the outside of the unit that it shouldn’t be wrapped.

Secondly, it’s important to consider the climate you live and where your heater is stored. If you live in a cold area and the heater is placed in the garage, it might require help to stay heated.

If you keep your heater inside your home, it may not need extra insulation since your house is keeping it warm. The bottom line is, if the external temperature differs significantly from the heater itself, it could benefit from a blanket.

Lastly, a good rule of thumb is to check the outside temperature of the water heater. You can simply place your hand on the unit, and if it feels warm or hot, insulation is needed.

How to Choose the Best Water Heater Blanket

Here are a few things you will want to consider before buying a water heater blanket.


The two most common water heater blanket materials are foil and fiberglass, which are also the most efficient insulation. Cotton and denim are less popular materials.

Fiberglass is great at insulating. However, it can be difficult to work with. It’s highly advised that you wear protective gear such as gloves and a mask. Foil is easy to work with but not as effective as fiberglass.

Fire resistance is also an important consideration — most blankets hold a fire rating of “class 1/class A.” This means they are less likely to catch fire if it were to happen. Fiberglass is considered non-flammable; cotton, on the other hand, is flammable (4).

Size and Thickness

A water heater blanket has to have the right fit to work properly. Thankfully, finding the correct size is easy.

All you have to know is the capacity of your heater, for example, 40 or 80 gallons. The blanket should state which size tank it fits; then you can buy accordingly.

The thickness of the insulation blanket is also something you may want to consider. Ideally, you would choose the thickest material for the best insulation. Insulation blankets can be up to 5-inches thick.

However, foil blankets are an exception to the thickness rule. Foil blankets don’t have to be particularly thick as they reflect the heat instead of absorbing it. Therefore, foil reflects and traps heat between the tank and blanket.

The Best Water Heater Blankets of 2021

Whether you have a gas or electric heater, here are five excellent water heater blankets to consider.

1. SmartShield Reflective Insulation Roll

Best Water Heater Blanket for Multiple Uses

This reflective insulation shield has many uses, such as insulation for water heaters and flooring. The insulation is made up of reflective foil layers with polyethylene foam in between.

The insulation is non-toxic, and it holds a class 1/class A fire rating. It won’t be the cause for any allergic reactions, as it doesn’t contain fiberglass.

It’s got a vapor barrier, so you won’t have to worry about mold or other damage caused by moisture. It can even be used outdoors as well. Therefore, if you have a heater exposed to the elements, this would be great.

You get 24 inches by 50 inches worth of insulation with this product. You can then cut it to fit your tank. Keep in mind; this is not a kit. Therefore, you won’t be provided with any extras such as tape.

Why We Love It

Double Layered Foil

You’ll get great insulation with the two layers of foil with foam in between. It not only reflects the lost heat back to the tank but also absorbs and holds the heat.

Vapor Barrier Keeps It Dry

The vapor barrier absorbs any moisture that might be present. It will also prevent mold from forming, helping the blanket last and keeping you safe.

Good for Indoors and Outdoors

Due to the durable barrier, you can use it outdoors. If you have a heater in a partially covered area or maybe in a cold basement, this will help it stay at temperature.

Non-Toxic Materials

The insulation doesn’t contain any material which could cause allergic reactions. For families with children, this could be an important point, as children are often more sensitive.

Keep In Mind

Doesn’t Come With Tape or Instructions

Unfortunately, that’s the downside of this product. It’s not exactly a kit. Therefore, you won’t be provided with instructions or extras such as tape. But, these are easy to overcome — many choose to use gaffer tape to seal the blanket.

Additional Specs

Weight 3.4 pounds
Dimensions 24 inches x 50 feet, 3mm. thick
Material Aluminum foil, polyethylene foam
Extras None

2. SmartJacket Water Heater Blanket

Best Material

If you’re looking for something easy to set up, this blanket might be where it’s at. It fits all tanks from 30 to 80 gallons and can also be used on either gas or electric.

The blanket has an R-value of 7.1, which means you could reduce heat loss by up to 40 percent. It’s easy to install as all you have to do is fit it around pipes and vents. Then, cut as needed and wrap it around.

You’re provided with tape and easy-to-follow instructions. However, some customers have mentioned that the tape isn’t as strong as they’d like.

The blanket consists of two sides of aluminum foil with a closed-cell polyethylene foam in between. The closed-cell foam is a leading insulation material (5).

Why We Love It

Fits a Range of Sizes

The size of the blanket means it can easily fit on tanks ranging from 30 to 80 gallons. You also won’t have to guess the size of your heater if you’re a first-time blanket buyer.

Easy Installment

To fit the blanket, all you have to do is measure around pipes and vents. This blanket doesn’t contain any fiberglass, so you also won’t have to wear protective gear.

Instructions and Tape Are Included

To make the installment even easier, you’re provided with instructions and tape. The instructions are in-depth and even show you what tools you’ll need.

Keep In Mind

Customers Felt the Tape Wasn’t Strong Enough

Some customers found the tape would fall off after a certain amount of time. Many recommend using a stronger tape from the start.

Additional Specs

Weight 2.35 pounds
Dimensions 5mm. thick, 84 inches by 24 inches
Material Double-sided aluminum foil, closed-cell polyethylene foam
Extras Tape and instructions

3. Frost King Water Heater Blanket

Best All-Season Insulation

After spending a few winters with limited hot water, this blanket would’ve been helpful. It’s a 3-inch thick fiberglass insulation jacket with a vinyl back. It claims to fit tanks up to 60 gallons. However, customers have found it depends on the type of unit you have.

This blanket is safe to use on all types of water heaters. Still, it’s important to leave all vents free if you have a gas tank.

Vinyl is often used on fiberglass insulation. Fiberglass absorbs and holds hot air, while the vinyl prevents moisture from passing through the insulation. This will not only make the blanket last longer, but it also means your heater will be dry and mold-free.

If you’re a do-it-yourself type of person, you’ll love this kit. You’ll get all the things you need to set up the blanket, including instructions and tape.

Why We Love It

Safe for All Types of Water Heaters

This fiberglass insulation blanket is safe to use on gas, electric, and oil water heaters. This means you won’t have to search day and night to find the right one. Also, if you were to get a new unit, you could still use the same blanket.

Thick Fiberglass Insulation

One of the main reasons why we like this product is due to the insulation. Fiberglass is one of the leading insulation materials. It’s used worldwide to insulate houses and pipes, and it will keep you from losing valuable energy.

The Vinyl Back Keeps It Safe From Water and Mold Damage

Vinyl is one of the most used materials, along with fiberglass. It typically has a black or white exterior, and it keeps out moisture which could damage the blanket and tank. Overall, the vinyl could make the blanket last for many years.

Keep In Mind

Customers Have Noted That It Just Barely Fits a 40-Gallon Tank

A few customers have noted the size of the blanket isn’t as grand as one might think. Some had difficulties getting it to fit a 40-gallon tank.

Additional Specs

Weight 6.55 pounds
Dimensions 3-inches thick, 60 inches by 90 inches
Materials Fiberglass and vinyl
Extras Plastic tape

4. US Energy Products Insulation Blanket

Best Lightweight Water Heater Blanket

If you’re looking for a water heater blanket that won’t take up a huge amount of space, this could be it. The aluminum foil makes this blanket super thin and lightweight — it’s only about 1.25-inches thick.

With the kit, you’ll get 42 square feet of material. That is 4 feet by 7 feet, plus a smaller 2 feet by 7 feet piece. The blanket has a high R-value of 7.2, which means you can save even more on your energy bills.

Even though foil isn’t as popular as fiberglass, it doesn’t mean it isn’t as effective. The foil reflects the heat radiation which the tank emits. It then sends the heat back, keeping the tank at temperature.

This blanket contains no fiberglass or toxic materials, so it’s safe for you and the environment. Due to the large size, the blanket could fit any tank between 20 gallons and 80 gallons. It’s also safe for gas and electric heaters.

Why We Love It

Large Amount of Material

You get great value for your money in terms of material. You get 42 square feet of foil, which comes in two pieces, one large and one smaller piece. The amount of material means you could wrap it twice if needed depending on the tank’s size.

Free of Toxic Materials

Even though fiberglass is great at insulating, it can be dangerous to handle, and exposure could lead to skin irritation (6). Foil insulation doesn’t come with as many risks. Therefore, you won’t need any protective gear.

Thin and Lightweight

You might have limited space around your heater. Therefore, a thick blanket won’t work. This foil blanket can easily go around even the tightest corner.

High R-Value

The foil blanket has an R-value of 7.2, which means it will limit the heat wasted. If you’re looking to save energy but don’t have room for a thick blanket, this could be great.

Keep In Mind

Some Customers Felt It Didn’t Hold Enough Heat

A few customers commented on how thin the product is. Many felt it didn’t make any difference.

Additional Specs

Weight N/A
Dimensions 4 feet by 7 feet / 2 feet by 7 feet
Material Foil
Extras Aluminum foil tape

5. Reflective Foil Water Tank Heater Insulation Jacket

Best Fire Resistance Water Heater Blanket

This insulation blanket is one of the most fire-resistant on the market. It’s all foil, and even though foil can burn, it isn’t as potentially hazardous as foam.

It has a class 1/class A fire rating which means it won’t spread fire as quickly as other materials. The blanket is patented reflective foil, and it reflects all the lost heat right back to the tank.

You get a large kit complete with everything you need to fit the blanket to your heater. You will get 48 inches by 76 inches of foil to work with. You also get foil tape, foil spacers, and instructions to fit your blanket perfectly.

The material is approximately 0.19-inches thick, and it consists of layers of foil with polyethylene bubbles in between. The blanket fits 50 and 60-gallon tanks.

Why We Love It

Safe, Non-Toxic Materials

For anyone who wants to be good on themselves and the environment, this could be beneficial. The blanket is thin and doesn’t contain any dangerous fillers.

You Get Plenty of Material

You get quite a lot of material, and it should be able to fit a 50 or 60-gallon tank. If yours is smaller, it’s easy to cut. A few customers mentioned they had enough for two tanks.

Kit Includes Everything You’ll Need

The kit includes tape and spacers, and you also get instructions, so it’s fairly easy to get started. You may need more than two hands to fit it perfectly, though.

Keep In Mind

A Few Users Mentioned It Was Difficult for One Person to Install

To fit the blanket perfectly on the tank, you may need some assistance. A few customers found it difficult — it might be due to the large amount of material.

Additional Specs

Weight 1.3 pounds
Dimensions 76 inches by 48 inches
Material Patented reflective foil
Extras Foil spacers, foil tape, and instructions

Water Heater Blanket Comparison Chart

Product Award Weight Dimensions Material Extras
SmartShield Reflective Insulation Best For Multiple Uses 3.4 lbs 50′ x 24″ x 3 mm Aluminum foil, polyethylene foam None
SmartJacket Blanket Best Material 2.35 lbs 84″ x 24″ x 5 mm Aluminum foil, polyethylene foam Tape
Frost King Blanket Best All-Season 6.55 lbs 90″ x 60″ x 3″ Fiberglass and vinyl Plastic tape
US Energy Products Best Lightweight N/A 4′ x 7′ / 2′ x 7′ Foil Aluminum foil tape
Reflective Foil Blanket Best Fire Resistance 2 lbs 76″ x 72″ x 1″ Patented reflective foil Foil spacers, foil tape

How to Install a Water Heater Blanket

When installing the blanket, it’s crucial to fit it correctly. How you fit it depends on whether you have an electric or gas-powered water heater.

1. Electric Heaters

With an electric water heater, it’s important to cut the blanket to fit around the panels and valves. There’s usually a controller, pressure valve, and a temperature relief valve on an electric heater. You can simply cut holes in the blanket to fit around these parts.

Electric heaters tend to lose a bit of heat from underneath. What you could do is cover the bottom of the heater as well.

Once you have installed a water heater blanket, it’s important to never set the temperature above 130 degrees Fahrenheit. Setting the temperature too high could cause the wiring to overheat.

2. Gas-Powered Heaters

Be Careful

With a gas-powered heater, you’ll want to be a bit more careful. You must never cover the top part of the heater.

The top part of the heater is where the exhaust is; covering this part will prevent the fumes from exiting. You should also leave the bottom unwrapped. This could lead to a build-up of dangerous gasses.

Headshot of Peter Gray

About the Author

Peter Gray

Peter has been a homeowner for 35+ years and has always done his own repair and improvement tasks. As a retired plumber, Peter now spends his time teaching others how they can fix leaks, replace faucets, and make home improvements on a budget.