The best garage air conditioners are those that are efficient and powerful.
In this Best Garage AC guide, we discuss the types that will keep the garage cool – and one that won’t.
Plus, there are a bunch of links to useful pages on the various types and additional information that will help you select the best type and size for your garage.
Here are the best air conditionerstypes for garages.
Ductless Mini Split Air Conditioners
These units represent the current state of the art in residential air conditioning and heating. If you use the garage a lot and want it cool and dry, this is easily the best choice.
About mini split systems: The name is a take-off on standard split system AC and heat pump systems. The equipment is smaller and, most importantly, no ductwork is required.
- A condensing unit is installed on the outside of the garage. It contains a compressor that circulates refrigerant.
- Usually one indoor unit, but sometimes two or three, are installed in the garage. There are several types of indoor units, but wall-mounted units are the most common. The units are mounted high on the wall and employ a powerful fan to distribute cooled air around the room, and heated air when desired, since most ductless systems are heat pumps.
- A power line and refrigerant line set connect the two units through a small hole cut through the wall, and a condensate drain carries water from the indoor unit out of the garage
Pros and cons of a ductless mini split air conditioner for the garage: First, the upside.
- Efficiency – they have the highest SEER/EER ratings of any type. They start at about 16 SEER/13 EER but range to 35+ SEER/25+ EER. That is far higher than other garage AC types.
- Size – Systems with a single indoor unit range in capacity from 6,000 BTUs for a one-car garage in a mild climate to 42,000 BTUs for a 3+ car garage in a hot climate. Got a bigger garage? A larger system with multiple indoor units will serve you well.
- Heat – If your winters are cold, then heat is awesome! Whether you’re leaving the house or returning home in sub-freezing weather or want to work on your car or workbench during winter, a heated garage has high value. And if you sell your home, it will catch the eye of potential buyers. Some of these amazing ductless systems can generate plenty of heat in sub-freezing weather – a few like the
- DIY-friendly – A few mini split air conditioner systems and heat pumps are designed for DIY installation. We’ve prepared a guide with the best DIY models for you to consider. All of them are ideal for the garage.
Concerns about mini split air conditioners:
- Cost – A ductless system costs 2 to 5 times more than a window AC, portable AC or through the wall AC. The higher cost will be paid back over time because these systems are much more efficient. Plus, they are quieter and deliver better comfort control.
- Installation challenges – Even the DIY-friendly units are more difficult to install than setting a window AC on the windowsill and closing the window or wheeling in a portable AC.
Best Mini Split Air Conditioner Brands
There’s a lot more information in our Mini Split AC/Heat Pump Reviews, Prices and Buying Guide including costs, size requirements, efficiency ratings, features and more.
Mini Split Air Conditioner Prices
A ductless AC or heat pump with one indoor unit costs $600-$2,200 for the equipment – based on the size, efficiency and brand quality of the unit.
Installation cost starts at about $1,500 for a single zone system when you hire a pro. See complete mini split AC price information in our Buying Guide.
Through the Wall Air Conditioners
These units are much like window units without the need for a window. If you want to spend less than the cost of a mini-split but still want good performance, consider a through-the-wall AC.
About through the wall air conditioners: Also written through-the-wall air conditioners, these units require a rectangular whole to be cut in the wall. A metal “sleeve” fills the space, and the unit can be slid in and out when necessary.
Many homeowners leave their through the wall AC/heat pump in the garage wall or the wall of their home, covering them in winter to protect them from the elements. A few are heat pumps, so can be useful in winter too.
Pros and cons of through the wall air conditioners for the garage: Here are the pros.
- Efficiency – These units are more efficient than window ACs and portable ACs because they fit tight in the wall, though not nearly as efficient as mini split systems.
- Quiet operation – Because most of the unit is outside, and a wall separates you from the noise, your garage will be quieter.
- Safer than window units – Thieves have a harder time dislodging a through the wall AC and getting inside than they do with a window unit.
- Permanent installation – When installed permanently, there’s no seasonal (or more often) hassle of moving the AC.
- The view – These ACs don’t block window space.
- Some heat (this is a half pro/half con) – A few through-the-wall ACs also heat, so they can help warm the space in cold weather. However, they are not heat pumps. They have a space heater coil in them for heat. They don’t make as much heat, and space heating uses a lot of electricity, so it is expensive.
What’s not great about through the wall ACs:
- Limited sizes – If you have a one-car garage, or maybe a 1.5-car garage, you’ll probably be OK with a large through the wall AC. Especially if the walls and ceiling are insulated. In really warm weather, or trying to heat in very cold weather, a through-the-wall unit might not keep up.
Best Through the Wall AC Brands
Our Through the Wall AC Reviews and Buying Guide is loaded with FAQs, costs, brand reviews and more.
The top brands are:
- Arctic King
Through the Wall Air Conditioner Prices
Expect to pay $350-$1,000 for the AC based on the size and quality of the unit and whether it produces heat too.
Hiring a handyman to cut the hole in the wall and installing the unit will cost $250-$750 for most projects.
Window Air Conditioners
A window AC might get the job done if your garage already has a window the unit will fit into.
About window air conditioners: These popular air conditioners are available in 6,000 to 28,000 BTU models. They might produce enough cooling in small garages or 2-car garages in climates that are moderate to warm. Our Window AC Buying Guide has comprehensive information.
Pros and cons of window air conditioners for the garage: First, the pros:
- Affordability: These are the least expensive garage air conditioners.
- Decent efficiency: They’re not as efficient as mini split ACs, but there are many Energy Star-certified units.
- Features: Most have remotes, timers, oscillating louvers for airflow, multiple cooling levels and fan speeds, and auto-restart after a power outage. A few have WiFi that makes it easy to turn on the AC remotely ahead of time, so the garage is comfortable when you enter it.
The downside of window ACs for the garage:
- Installation: Unless your garage window has a sill, and most do not, you’ll have to install a bracket to support the AC.
- Noise: Of the three best AC types for garages, these are the LOUDEST.
- Window size: Many garage window aren’t the right size for a window air conditioner. There are a few vertical window/sliding window ACs, so that might be an option if you have a sliding/gliding window in your garage.
Best Window AC Brands
All these brands have models that might work well in a garage with an accommodating window:
What About Portable Air Conditioners?
Portable ACs have their place, but it is not in the garage. The reasons are many:
- They take up floor space and are likely to get dinged up in a garage setting.
- They have to be vented out a window.
- They aren’t as efficient as window and through the wall air conditioners, and come nowhere near the efficiency of mini split units.
- They’re not powerful enough to combat the heat and humidity often found in the garage. The largest are just 14,000 BTU, and that’s not going to get it done unless your summers are quite mild and a powerful fan would do just as well.
Portable air conditioners are a good fit in a bedroom, office, den or other enclosed space inside the house, but not ideal for the garage. Our Portable AC Reviews, Prices and Buying Guide has more information.
Sizing a Garage Air Conditioner
Since most garages don’t have as much insulation in the walls and ceiling as in the house, it is necessary to oversize the air conditioner. This table shows our recommended AC size for garages of various size. The notes that follow the chart should prove useful too.
|Square Feet||Garage Size||BTUs Recommended|
|150 - 250||1 Car||8,000|
|250 - 350||1.5 Cars||10,000|
|350 - 450||2 Cars||12,000|
|450 - 550||2 or 2.5 Cars||14,000|
|550 - 650||3 Cars||16,000|
|650 - 750||3 or 3.5 Cars||18,000|
|750 - 900||3.5 or 4 Cars||20,000|
Notes: You might need a bigger AC than shown in the chart.
1). Add 2,000 to 4,0000 BTUs if the garage is uninsulated (and see the next section on how to save money)
2). Add 1,000 to 2,000 BTUs if your garage faces south and/or west
3). Add 1,000 BTUs if your climate is very sunny (like Denver) rather than cloudy (like Houston)
4). Add 1,000 to 2,000 BTUs if your garage is in a very humid climate like the South, Southeast or Northeast
For example, consider a garage that is 22 x 24, or 528 square feet. That’s considered a 2.5-car garage or maybe a 3-car garage, but vehicles are getting bigger.
In Buffalo, NY, with 54 days of sun and relatively cool summers, a garage that faces north or east will be sufficiently cooled with a 14,000 BTU AC.
In Atlanta, GA, with 110 days of sun and torridly hot summers, a garage facing south or west better have an AC of at least 18,000 BTUs, and a 20,000 to 24,000 BTU AC would be even better.
We do not recommend over-sizing an AC for the house, especially a central AC or mini split AC. But in a garage, it is definitely OK to do.
Ways to Make your Garage More Energy Efficient
Very few garages have the same insulation levels (R-value) as the home. For most homeowners, there’s no need to insulate unheated and un-cooled space, so why spend money on insulation?
But you’re reading this because you plan to use the garage for more than parking space and storage. That much is clear.
First Steps to a Cool & Comfortable Garage
You’ve got two options, and we think the “both/and” solution is way better than “either/or.”
First, insulate and seal your garage to living space specifications according to EnergyStar.gov. House wrap (aka vapor barrier or WRB – weather resistant barrier) insulation and sealing gaps around outlets, doors and windows is cheap. The money you spend will be paid back through lower energy costs in 2-10 years depending on your climate – the hotter your climate, the faster the payback time.
If you choose a heat pump to be your garage air conditioner, then factor in cold winters too. Insulation and sealing gaps will save money on heating costs from day one.
In short, adding insulation has the highest return on investment, or ROI, of any home remodeling project. You can attach lightweight 1” or 2” foam board installation to the inside of most garage doors without impeding their operation. And it will definitely improve insulation.
Secondly, choose a powerful and efficient air conditioner that is a bit oversized for the square footage of your garage, as we’ve said. This is true unless you’ve already taken the first point to heart and insulated your garage as well as your home is insulated.
Thirdly, get the hot air out first. If your garage has been shut up all day, the air in there might be quite warm. Raise the garage door about a foot. Open the access door and windows, if you have them. Use a fan to blow air out the window, pulling in fresh air from other locations. You might also consider investing in several roof vents in the garage roof.
All these steps will allow airflow that will clear out much of the hot air before you turn on the AC. The garage will cool faster and more efficiently – and keep your utility bills in the sane range.
Image Credit: ComfortUp.com