What Size Garage Heater Do I Need?

The frigid temperatures that come with wintertime need not slow you down. With a garage heater, you can continue to take advantage of your valuable garage space all year long – but you might be wondering, “what size garage heater do I need?” Learn more here.  

Should I Use a Garage Heater?

Should I Use a Garage Heater

Garage heaters provide many benefits for you, your home, and your projects. 

If the garage is your workshop, you no longer have to stop working because the temperatures drop. You can continue tinkering with your projects all winter long.

Believe it or not, garage heaters help increase storage space. Temperature-sensitive items that were once kept in the home can now be safely stored in the warm garage.

Heated garages help protect your vehicles from freezing temperatures. Not to mention that it’s much more comfortable getting into a non-freezing car before work!

If you are in the market for a garage heater, then keep on reading to learn all there is to know about finding the perfect heater for your garage.    

What Size Garage Heater Do I Need? 

When deciding what size garage heater you need, the short answer is that it depends. The size of the garage heater you should use will ultimately reflect the size of your garage. 

If you purchase a garage heater that is too small for the space, it will end up working too hard and expend too much energy. If you buy a garage heater that is too large for your garage, you will end up wasting money on heating power that you are not utilizing. 

To find the perfect heater size for your garage, you will need to do some calculations. 

How to Calculate the Size of Your Garage Heater

Depending on your mathematical prowess, there are a couple of ways to calculate the size of garage heater your space requires. The calculations will depend on: 

  • Your climate and weather conditions
  • The size of your garage
  • The ceiling height of your garage
  • The level of insulation 
  • Whether it is an attached or detached garage

The simplest way to estimate the size of the heater you require is to follow this basic rule of thumb: 10 watts per square foot. 

For example, a 22 ft. x 24 ft. garage has 528 square feet. 528 x 10 = 5,280 watts. Therefore, you will need a garage heater that produces 5,280 watts or slightly more.

On the other hand, gas heaters are measured in British Thermal Units or BTUs. If you are purchasing a gas heater, you will need to convert your solution from watts to BTUs. 

To estimate the size of a gas garage heater, simply multiply the wattage by 3.41. So, 5,280 x 3.41 = 18,005 BTUs.

As we mentioned, this is by far the most basic method for beginning to think about the size of the garage heater you need. 

For a much more detailed explanation, have a look at this video:

What Are the Risks of Using a Heater in the Garage?

Using a garage heater does not come without its own set of risks. This is especially true for gas-powered garage heaters. During the heating process, gas heaters can emit carbon monoxide, an odorless and deadly gas. Proper ventilation is vital for the safe operation of gas heaters. 

Portable heaters also come with risks. Due to their smaller size, it’s easier to knock them over by mistake. Luckily, modern portable heaters have a safety feature that shuts the heater off if it topples over – make sure you buy a heater with this feature to stay safe. 

With forced air heaters, there is a risk that debris can fall into the heater and catch fire. And of course, there is a risk of burning oneself if you come in close contact with the heater. 

To avoid the risks associated with garage heaters, make sure to consult a professional when installing a more complex heating system. As for simpler, portable heating systems, remember to always consult the manufacturer’s guidelines for proper and safe usage.

What Kind of Heater is Best for the Garage?

When it comes to the best kind of heater for your garage, there are four types of heaters to consider. These include mounted or fixed heaters, portable heaters, forced air heaters, and tank top heaters. 

Mounted or Fixed Heaters

Mounted heaters are permanent heating units that are fixed in place to the ceiling or walls of your garage. Mounted heaters are often the largest and most powerful heating option available. If needed, they can produce up to 20,000 BTUs of energy per hour. 

Portable Heaters

Portable heaters come in a variety of shapes and sizes. They are electric heaters that require a 110-volt socket outlet for power. 

Smaller models are handheld and can be easily stowed away when not in use during the warmer months. Some larger portable heaters come with wheels for easy portability around the garage.

Portable garage heaters are typically able to provide up to 35,000 BTUs of energy per hour. 

Forced Air Heaters

Forced air garage heaters use a fan to blow air into a heating element which then exits the heater and heats the surrounding air. Because of the fan, it’s forced are heaters need to be positioned at least 10-feet away from any wall or object.

Forced air heaters are electric and require a 110-volt socket outlet. They should not be positioned near any flammable liquid or objects, such as gasoline or paint thinners. 

Depending on the size, this type of heater is able to produce between 30,000 and 40,000 BTUs of energy per hour. 

Tank Top Heaters

Tan top heaters use a heating element to heat up and emit radiant heat into your garage. They also use water stored in an internal reservoir to generate more heat. 

Electricity powers tank top heaters and require a 110-volt socket outlet for power. They are capable of producing 40,000 BTUs of energy per hour. 

What to Consider When Putting a Heater in the Garage

What to Consider When Putting a Heater in the Garage

There is a lot to consider when putting a heater into the garage. 

Climate and Location

Your geographic location and the local weather will say a lot about what type of heater your garage requires. Obviously, the colder the climate is in your zone, the larger and more powerful of a heater you will need. 

Size of Garage

The size of your garage is the single most important thing to consider when putting a heater in your garage.

Quality of Insulation

Newer buildings are constructed with a lot more insulation than older buildings. Knowing the age of your garage and how its construction will help determine the quality of insulation it has.

Doors and Windows

The presence of windows and doors in your garage will affect the size of the heater you need. Oftentimes, the more windows and doors you have, the more heating you will require.

Mounted or Portable 

Mounted heaters are permanent fixtures in your garage. Portable heaters can be stored away during the warmer months and brought out for the winter. 

How Many BTUs Do I Need to Heat My Garage?

British thermal units, or BTUs, are the common unit of measurement for heating systems. The amount of BTUs you need will depend on a number of different factors.  

In order to determine the amount of BTUs you need to heat your garage, you will need to do some calculations based on the garage size, climate, type of insulation (also known as the R-value), and other variables. 

Usually, you will need somewhere between 30-60 BTUs. 

Choosing the Right Garage Heater

Choosing the right garage heater will take some time and a little bit of research. But the process is very important for making the right decision. The last thing you want to do is invest in a heater that is the incorrect size for your garage. 

Considering how much time your garage space will be needed, the type of ventilation your garage has (or doesn’t have), and how much heating power you need to accomplish your goals are all part of the decision-making process. Good luck! And may your garage ever be warm and toasty

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