Can I Put A Mini Split In My Garage? [Pros And Cons]

Today’s garages are much more than carports and storage spaces. We use them for everything from workshops and rec rooms to home offices and classrooms. As a result, we need better heating and cooling for them. 

It’s tempting to consider extending the ductwork from your house into the garage. After all, you already have a heating and cooling system. Why not make the most of it? 

The bad news is that it’s more complex than that. The good news is that there’s a better solution on the market. Ductless air conditioners, or mini splits, can heat and cool a garage. And they can do a better job of it than traditional HVAC solutions. 


I’ve followed closely as these systems have soared in popularity over the past fifteen years. I’ve spent over a decade as a product manager for Peirce Phelps, a major national HVAC distributor. 

In that time, I’ve followed all the industry developments and worked closely with contractors who’ve installed thousands of units across Pennsylvania, New Jersey, Delaware, and Maryland. 


As the heat pump technology behind mini splits improved, these systems became much more common in the mid-Atlantic states. 

In this blog, we will explore the pros and cons of both options to help you make an informed decision. If you have more questions, you can schedule a free consultation with a certified installer that’s worked in your area for years. Just use the Dealer Locator button below to find the right one for you. 

Pros and Cons of Extending Ductwork into a Garage

Extending ductwork into a garage is an option if you already have a central HVAC system. But it’s not necessarily the best one. Here are some pros and cons of extending ductwork into your garage.

Pros of Extending Ductwork into a Garage

Despite some challenges, there are some benefits to extending ductwork from your home into the garage:

Increase Home Value

A garage with heating and cooling is valuable for buyers who want a workshop, additional living space, or a more comfortable walk to the car on winter or summer mornings. 

Permanent Climate Control

Your home’s forced-air system is more convenient than space heaters or window ACs. It’s also safer: Space heaters are fire hazards, and burglars can access your house by pushing in a window unit. 


Extending ductwork means tapping into the system you already have. You don’t have to choose a new system or wire another thermostat. 

Cons of Extending Ductwork into a Garage

In most cases, there are more drawbacks than benefits to extending ductwork into a garage:


Extending ductwork into a garage is expensive. Having someone design the run and fabricate the ducts is expensive. Then, there’s a lot of invasive construction to run a new trunk from the furnace up through the house. Since garages are usually on a slab, there’s no basement beneath them, making it more difficult. 

Poor Performance

You won’t get the same pressure in the garage as you do on the first floor of your house. In fact, you’ll get weaker heating and cooling overall. Your furnace is sized for the square footage it treats. Adding a few hundred more feet means it’s straining its resources over a larger space. 

Higher Bills

Even if you don’t get the heating and cooling you want, you’ll still pay much more to keep your system running longer and harder. 

Benefits Of A Ductless Air Conditioner For a Garage

A ductless mini split air conditioning system is a great HVAC option for converting your garage into a living space. The benefits include:

Customized Heating and Cooling

You can adjust the temperature for just the garage, which allows for more precise control over the indoor climate and greater energy efficiency. And even though it’s sometimes called a “ductless AC,” a mini split can heat a room just as well as it can cool it. 

Easy Installation

A ductless mini split air conditioning system does not require extensive ductwork installation, which can be costly and time-consuming. Installing a ductless mini split air conditioning system involves mounting the indoor unit on the wall, mounting the heat pump outside, connecting the components with a refrigerant line via a small hole through the wall, and then powering the components. It takes less than a day. 

Energy Efficiency

Ductless mini split air conditioning systems are Energy Star certified with high SEER ratings. They use inverter technology to adjust their compressor speed based on the heating or cooling needs of the garage. That means they don’t just turn on full blast until the room is the temperature you want and then shut off until the temperature drifts again. Those on/off cycles waste energy by having to power on all the time. 

Lower Bills

Thanks to their energy efficiency, a mini split air helps lower your bills by using less energy than other systems. If you have yet to have heating or cooling in the garage, you’ll barely notice a difference in your bills. You’ll see a significant drop if you convert from space heaters and window ACs. 

Drawbacks of a Mini Split for a Garage

While ductless mini split air conditioning systems have many benefits, they also have a few drawbacks, including:

Higher Upfront Cost Than Portable Units

Ductless mini split air conditioning systems are much more expensive than portable units like window air conditioners or space heaters. A single-zone starts around $3,500. It’s a great investment in the long run, but it can be a budgetary challenge initially. 

Planning To Install A Mini Split In Garage

Installing a mini split for a garage is simple and straight forward. It requires an installer to mount the air handler on an exterior wall with the outdoor unit right on the other side of it. Then run a line set through the wall to connect the two. A single-zone install takes less than a day with no major construction.

Estimate What Size Mini Split You’ll Need By Square Footage

Single zone mini splits come in different capacities (and costs) depending on their strength. You’ll need a certified HVAC tech to do a load calculation to determine what size system you’ll need. It takes into account many factors besides just the garage size. 

One of the most significant factors when it comes to a garage is insulation. You can start with the basic rule that you need 100 BTUs for every 20 feet you want to heat or cool. But, if your garage is very drafty, you’ll need more capacity than you would for the same amount of space inside. 

But you can use these basic estimates as an idea of what to expect: 

One-Car Garage

A 9,000 BTU mini split is often sufficient to heat and cool a garage with a square footage of around 400. 

Two-Car Garage

Because a two-car garage has larger square footage, usually 500 feet or more, you’ll need a 12,000 BTU system. 

Three-Car Garage

A three-car garage has a lot of space to treat. Depending on the exact layout and factors, your HVAC contractor may recommend a model with 18,000 BTU capacity. Or, they’ll suggest two air handlers on opposite sides to ensure the entire space gets enough heat or air conditioning,

Cost To Install A Mini Split In A Garage

The cost of installing a mini-split unit in a garage varies depending on the unit’s size and the 

installation’s complexity. The average is $3,500 for a single-zone system, which is enough for most garages. The cost increases with every air handler.

Garage Mini Split FAQs

Hopefully, you have the information about a garage mini split to decide whether it’s a good fit for your needs I’ll answer and summarize a few more points below. 

If you have more questions, especially anything specific to your home or neighborhood, your best bet is to schedule a free consultation with one of our network dealers. They’re certified to install Bryant equipment and have excellent, long-standing reputations in their respective areas. 


Can you put an air conditioner in a garage? 

Yes, you can put an air conditioner in a garage. Through-the-wall units are cheap but loud and use a lot of electricity. Extending ductwork from central air is costly and doesn’t work well. Ductless mini split systems are efficient and convenient for garages. 

Do ductless mini splits use a lot of electricity? 

Ductless mini split systems do not use a lot of electricity and less energy than comparable furnaces and central air systems. These high-efficiency systems can save you money on your energy bills while providing comfortable heating and cooling. 

How many square feet is a mini split good for? 

The square footage that a mini split is good for depends on the unit’s cooling output, which is measured in BTUs. A 9,000 BTU mini split can typically cool an area of 300-400 square feet. A 12,000 BTU unit can cool up to 500 square feet.

How many years do mini splits last?

Mini split units are designed to be durable and long-lasting. A mini split can last up to 20 years or more with proper maintenance and care. They can keep their efficiency, meaning they won’t require more energy over time. So, your bills should stay the same over the years. 

Find the best ductless air conditioner installer in Cherry Hill, PA or anywhere in New Jersey, Pennsylvania, Maryland, or Delaware.