Best Way To Heat A Detached Garage? [A Detailed Guide]

Garage Storage Lab is reader-supported. When you buy through links on our site, we may earn an affiliate commission.

If you’re a DIY enthusiast with a detached garage facility, I’m sure you enjoy spending time there, apart from just keeping your car.

That said, during winter things can turn the other way around. Paces like a detached garage don’t benefit from the heat of your house and get cold in this particular season. As a result, you may lose your will to finish a project (let’s say woodworking!) on time.

best way to heat a detached garage

Even worse, you may find your valuables getting wet and exposed to the elements. That being said, there is a range of ways you can implement and keep the garage heated. Then the question arises,

What is the best way to heat a detached garage?

If storing cars or everyday items is the primary purpose to use a detached garage, simple insulation could be enough.

But, if you have mechanical accessories and the garage is your prominent workstation you should opt for garage heaters. Among various options, installing a multi-split ductless heater is the most efficient way to heat a detached garage.  

Talking about keeping a garage (detached) heated, there is a lot more you need to know about. And, I will discuss all of them today. So, without further ado, let’s keep this rolling.

Better Insulation: Stop Losing Heat In The First Place

If you live in an area where winter is relatively mild, you can easily get away with insulating your garage. Insulation prevents cold air from coming in, thus keeping your garage warmer than the outside.

Without proper insulation, buying garage heaters won’t work, since warm air will escape through the window/door or wall. With insulation, you can prevent this loss and keep the heat inside.

The good news is, insulation is cheap and doesn’t involve big overhauls. You just need to purchase a few fiberglass insulation rolls and use your knife and staple gun to fit the size of the wall and the ceiling.

In addition, you have to seal the exterior doors and cracks around the windows. Applying weather stripping provides the simplest solution here.


  • No recurring costs after installation
  • The project is easy enough for an average person to implement
  • Versatile; You can insulate anything including walls, doors, and windows
  • Insulation materials (like fiberglass roll/foam boars/spray foam) are inexpensive


  • Relying on insulation only isn’t effective for locations where temperatures drop too low
  • You have limited control over the temperature inside the garage

Best Ways To Heat A Detached Garage

In the beginning, we talked about insulation and keeping your garage unaffected by external elements. However, if extreme cold is something you experience each year consider heating options along with it.

Space Heaters

If you need the simplest route to keep your garage heated, using a space heater is your best option. They are versatile since you can easily mount one on the wall, from the ceiling, or even use it in your house.

You just need to buy a suitable size option according to how big the garage is. The rest is finding a spot to plug in the heater, and it’ll keep the place warm within a few minutes.

Types of Portable Heaters:


  • Portable and hence very easy to use
  • Doesn’t require a ventilation system
  • Energy-efficient so electricity bill won’t a big concern


  • Not suitable for heating big garages

Radiant Heaters

If you live in a colder place, radiant heaters will suit you better. These use infrared tubes to reflect radiated heat around the garage instead of forcing them into the air. They can be attached to the wall or hung from the ceiling.

Although the installation cost is a bit higher than the space heaters, you won’t incur much to operate them.


  • Quick to install
  • Low operating costs
  • Can produce powerful heat
  • Heat a garage surface evenly   
  • Doesn’t require much energy to heat up


  • Greater risk of fire hazards

Multi-split Ductless Heating

Multi-split ductless heaters are the most comfortable garage heating solution. The system works quite similarly to air conditioning. The process requires installing two units:

  • An air handling-unit
  • Compressor

The first component is fitted inside the garage and the last one is installed outside. A conduit connect them. They use electricity to generate heat.

But the biggest selling point is the cooling feature they provide. Since they also have a remote control facility using them in the summer is effortless. However, you will need to hire a HAVC professional for the initial setup. So the upfront cost is steeper than regular garage heaters.


  • Very convenient to use
  • Most flexible garage heaters
  • Can be used in the summer
  • They are quite an energy efficient
  • Easier to install than in-floor heating


  • Require scheduled/routine cleaning

Frequently Asked Questions

Q1. What temperature should I keep in my garage in the winter?

There isn’t a solid answer because it can vary depending on your geographical location. To avoid condensation it is advised to keep the temperature in your garage above the dew point. If you live in inland states it’s around 40F whereas for coastal areas it’s 65F on average. 

Q2. Is a heated garage bad for cars?

Going out and then coming back with snow into the heated garage isn’t good for your cars. The extra humidity will melt those ice and salt and later on may lead to rust forming. Shifting the car between a hot and cold environment may also damage the seals.

Instead, opt for installing better insulation. This way, you can save the battery and prolong your car’s life by storing it in the garage.

Q3. How many BTU heaters do I need?

There is easy math to do here. Just multiply your square foot number by 30 and you’ll find the answer. For instance, if your garage floor size is 800 sq. ft then you need a 24,000 BTU heater to keep it warm.

Q4. How much does it cost to heat a detached garage?

Depending on the type of heaters the cost can range from $100 to $800.

1. The average price for electric heaters: 100-400 USD
2. The average price for propane heaters: is 150-450 USD
3. The average price for gas heaters: is 400-800 USD

Final Words

Coming to the end, I hope, the above information is useful for you to decide on the best way to heat a detached garage this winter. Honestly speaking, winter doesn’t have to stop you from working on your hobbies.

Just keep your budget in mind. It shouldn’t be too difficult to find the best heaters and insulators for your specific condition. Lastly, I hope your garage stays warm and cozy all year round.

Hi, I am Brent Hartman. I am a DIY enthusiast and love to improve and organize the garage in the most innovative way. I created this website out of my passion for helping people organize their garages.

As an Amazon Associate I earn from qualifying purchases.