How To Keep Beer Warm While Brewing

There are many elements to homemade beer that require precision and attention to detail, including the strain of yeast and the temperature of your wort during the fermentation process. While most strains can be fermented at varying temperatures, some need to stay warmer during the brewing process.

To keep beer warm while brewing, you can use an electric belt, a heating blanket, or a pan of hot water. You can also use insulated foam or layered towels to help maintain the temperature. Another option is to purchase a fermentation chamber, which sustains your brew at a preset temperature.

Maintaining a high temperature in certain strains is vital for the finished product to taste crisp and flavorful, but it can be challenging when living in cold environments or seasons. The remainder of this article will discuss the various ways to keep your beer warm during brewing, how to make your own chamber, and why temperature plays such a significant role in the overall process.

1. Use an Electric Belt or Heating Pad

An electric belt is a belt that wraps around the base of your fermentation container and plugs into a power source to heat up. It’s temperature controlled, so the belt makes it easy to maintain a specific temperature. This device is called a brew belt.

A heating pad can be specifically designed as a flat pad that your brew can sit atop. I highly recommend the Brewing & Fermentation Heat Pad (available on 

The pad has a heating strip that gives you the exact temperature it is warmed to. You can also use a regular electric heating pad if you have one on hand at home if purchasing one isn’t an option.

Both styles of the heating device are temperature controlled. However, a standard heating pad (used for backaches, menstrual cramps, and the like) will only have preset temps– think warm, hot, and very hot. Thus, a heating pad designed specifically for brewing or a brew belt is recommended here.

2. Use a Container of Hot Water

For the especially crafty folk, a simple container of hot water is all that’s needed to maintain their beer’s temperature. 

Unlike the electric devices, though, if you place your brewing container in another one of hot water, it will only sustain heat for so long before naturally cooling. So, be prepared to change the hot water every time it begins to cool.

Prior to placing the brew in hot water, make sure to check the water’s temperature. Most brews should be maintained between 68 and 74 degrees Fahrenheit (20 and 22 degrees Celsius). Any hotter or colder will disrupt the fermentation process and ruin the end product of your lager or ale.

While this is one of the most inexpensive options, it does require regular supervision and thus isn’t always as convenient as the electric devices. A similar device that will keep your brew warm without the need for constant supervision is an aquarium heater.

An aquarium heater is typically used to keep the water in an aquarium at a reasonable temperature so as not to harm the fish living within it. In this case, you can place your brew in a large container filled with water and connect it to an aquarium heater.

Of course, you don’t want the aquarium’s water to overflow into your brew, nor should you place the heater inside the brewing container. Instead, allow the heater to warm up the water that your brew container is sitting in. The heater will maintain this heat as long as it is plugged into an external power source.

3. Wrap the Container in Layered Towels or Linens

Another way to keep your brew warm during fermentation is by using hot, layered towels or linens to surround the container. In the past, I’ve either placed clothes in a large pot of boiling water or in a steaming hot bathtub. 

After about five to ten minutes of soaking the clothes, I pull them out and wrap them around the fermentation container.

It’s crucial to mention here that you should be using protective equipment at all times when handling boiling hot materials. 

When removing the clothes or linens from the water, make sure to wear waterproof gloves and use tongs so as not to burn your hands. If your linens are in a tub, you can drain the water before removing the necessary cloths.

Towels work best in this scenario because they are generally much thicker than linens. The thicker the material, the more heat it can absorb and maintain for lengthy periods of time. 

By layering the towels atop one another, you’re creating a barrier used to hold all of the heat inside the brewing container.

Similar to the makeshift aquarium heater, the towels will eventually lose their warmth and cool off, in which case you’ll need to replace them with freshly heated towels as soon as possible.

4. Invest in High-Quality Brewing Equipment

Finally, you may want to invest in high-quality brewing equipment to ensure that your brew is kept at an adequate temperature. 

There are many different kinds of fermentation devices on the market with all sorts of accessories to choose from, so keep reading for a guide on which devices are the best for beer brewing.

Steel Versus Aluminum

First of all, there are fermentation containers made from multiple different materials, such as steel, aluminum, glass, and plastic. While all of these materials are all equally usable, the steel and aluminum ones are better to use than plastic.

Steel metal is the best insulating material of the three, meaning that it will hold heat much longer and more effectively than aluminum or plastic. It’s also resistant to damage like scratches, which could compromise the wort through bacteria contamination. Unfortunately, it’s the most expensive of the four.

However, aluminum is the next best thing. If you’re looking for the best containers to ferment your beer, read more here for guidance on the seven best aluminum containers for beer fermentation.

Plastic Versus Glass

Plastic and glass are two other materials used for beer brewing, and like the example above– both are equally functional. Plastic is the cheaper option and easier to clean. It’s also an excellent long-term insulator. 

However, plastic fermenters scratch easily, and bacteria can gather in the crevices.

Glass, on the other hand, is resistant to scratches, so in that regard, it’s the longest-lasting of the four. However, while glass is a good insulator, glass fermenters are best for small brewing batches versus larger volumes of wort.

Overall, steel, aluminum, and plastic fermenters are the most efficient materials to look for when purchasing high-quality brewing equipment, with glass fermenters more appropriate for smaller brews.

It’s essential to note that fermenters are not the only pieces of equipment needed to brew homemade beer. Some other valuable items for beer brewing include:

  • Airlocks: An airlock used for fermentation allows gasses to escape while preventing external air from entering the fermenter. You can buy individual airlocks such as these MRbrew ones from Amazon.    
  • Stoppers: A stopper is used after the brewing to plug the glass jug or carboy that your brew is contained in. Inexpensive stoppers can be purchased along with airlocks and other fermentation equipment.
  • Jugs and carboys: A carboy is a style of jug used to store beer. Most carboys can be purchased at your local brewery or winery, but you can also find them on Amazon. These FastRack ones are an excellent choice.
  • Fermentation chambers: A fermentation chamber is a regulated chamber that keeps your homebrew at a regulated temperature. Check out this post on the best fermentation chambers. You can also buy fermentation chambers on Amazon.

These are only a few extra pieces of equipment. A detailed, thorough guide to brewing equipment can be found here. Read on to learn how to make your own fermentation chamber.

Homemade DIY Fermentation Chamber

The simplest way to ferment your own beer is to create your own fermentation chamber. In order to DIY this fermenter, you’ll need:

  • A clean, sterilized fridge
  • A greenhouse or aquarium heater
  • An inkbird controller
  • An external power source
  • A drill

Four Steps To Making a DIY Fermentation Chamber

Once you’ve collected all of the materials needed for your fermentation chamber, it’s time to get started.

  1. The fridge should be big enough to hold your fermentation container. Start by cleaning it appropriately (with a sterilizer– remember, you’re brewing beer in here!).
  2. Next, you can attach the greenhouse heater (or aquarium heater) to the inside of the fridge. The heater should not be touching the brew– just heating up the DIY chamber.
  3. Then, you’ll have to find a way to pass the cables from the heater and controller out of your fridge and to an external power source. Whether you drill a few holes into the fridge or pass it through the door, you must ensure that your DIY chamber is properly sealed.
  4. Finally, plug your heater and controller in. Before you’re finished, set the controller to the desired temperature.

Why Is Temperature Important for Beer Brewing?

Temperature is one of the most critical factors in creating a solid homebrew.

The reason is that it controls how slow or fast the yeast grows in the mash and produces alcohol from the wort. Different strains of yeast require different temperatures to ferment at an appropriate rate. The most common yeast strains used in beer brewing are lager strains and ale strains.

Lager beers are fermented in containers regulated between 48 and 58 degrees Fahrenheit (9 and 14 degrees Celsius). They’re different from ales because the yeast sits at the bottom of the container to ferment. 

Ales, on the other hand, require temperatures much hotter than that, ranging between 50 and 70 degrees Fahrenheit (10 and 21 degrees Celsius). With ales, yeast makes its way to the top of the brew to ferment.

When temperatures reach high levels, they change the yeast’s metabolism rate and affect the finished brew’s flavor profile. So, it’s mandatory to keep your wort at the appropriate temperature in order to brew it properly.

Luckily, yeast temperatures are a little easier to master with the knowledge that despite the hundreds of different strains, they are generally separated into lagers and ales according to their temperature preferences. 

Below are some examples of the different types of yeast strains and what temperatures they ferment best at:

  • Belgian Ale. 62-68 degrees Fahrenheit (17-20 degrees Celsius)
  • Mexican Lagers. 50-55 degrees Fahrenheit (10-13 degrees Celsius)
  • American Ale. 60-72 degrees Fahrenheit (16-22 degrees Celsius)
  • Brewferm. 64-77 degrees Fahrenheit (18-25 degrees Celsius)
  • German ale. 65-69 degrees Fahrenheit (18-21 degrees Celsius)
  • West Coast Ale. 60-73 degrees Fahrenheit (16-23 degrees Celsius)

Naturally, there are many more strains than the ones mentioned above. If you’re looking for resources specifically about the various strains, click here to start your journey reading about grains that first interact with yeast to make beer.

You can also check out Home Brew Advice on Youtube, which is the blog’s accompanying channel. It provides tons of great information on how to brew your own beer at home. For example, the following link will lead you to Home Brew Advice on how long your beer should stay in the fermenter:

Alternatively, if you’re new to the homebrewing process, you can watch the below link to learn about mash (pre-fermented liquid):

There are many more tools available online or in your local library or bookstore, and because home brewing takes practice and precision, it’s a good idea to educate yourself on its various complexities.


Ultimately, the best way to keep the beer warm while brewing is through the use of brewing equipment, heating devices, and aquarium or other DIY heaters. Some materials (like glass and plastic, for example) work differently as insulators during the fermentation process, so researching the best ones to use prior to purchase is a great idea. 

If you don’t have access to a heater, you can purchase a durable fermentation chamber that does the heating for you– or you can make one yourself! With these tips, keeping your beer warm during the brewing process should be a breeze.

About HomeBrewAdvice

Hello, my name is Simon. Together with a group of writers I write about brewing beer and making wine. We all share a passion for the great things in life, such as making stuff from scratch.

The business of HomeBrewAdvice is to bring you great information, stories and product reviews from brewing at home, and making wine

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