Should You Air Condition Your Garage? [Pros, Cons And How To]

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Garages are usually uninsulated and unattached to central cooling systems. This means that hot air builds up quickly and often sticks around. Due to this heat, you are wondering, should you air condition your garage? In this post, we combine industry professional knowledge and research to thoroughly answer your question.

If your hot garage is an impediment to comfort or item integrity, you should probably air condition your garage. However, before taking this step, ensure that you carefully consider this decision including all the advantages, disadvantages, and how-tos for undertaking this home improvement project. 

Read the rest of this post for details regarding whether to air condition a garage or not. We also include directions on how to choose and install your air conditioning properly. Importantly, we cover a common energy-wasting and potentially dangerous mistake many make when air conditioning their garage.

Inside a large empty garage, Should You Air Condition Your Garage? [Pros, Cons And How To]

Whether or Not to Air Condition Your Garage

When deciding whether or not to air condition your garage, a few issues are the most important to consider. These include the number of uncomfortably hot garage days, the reasons for air conditioning your garage, your budget, and whether you are including air conditioning in a new build or as a remodel.

Number of Hot Garage Days

Essentially, if you only have a few hot garage days per year, it is probably not worthwhile to air condition your garage. The additional expense and headache of garage air conditioning are too involved for just a few uses every summer.

On the other hand, if you live nearer to the equator and find that your garage is too hot for use for a month or more, it may very well be worth air conditioning your garage.

The decision about too many hot days depends on you and your family’s personal tolerance, and on the several additional garage air conditioning considerations discussed below. Each garage and garage user is unique, so read carefully.

Reason For Air Conditioning

The main reason people air condition their garage is for stored item longevity and for personal comfort. Sometimes, air conditioning is installed for a combination of these reasons. The details of the issues that air conditioning solves are discussed in this section.

Photo of clean garage with ladder and other tools

Intense, prolonged heat can damage cars, paints, lumber, other building materials, tools, collectibles, and more. Each item has a different heat tolerance which can usually be researched online.

Using a thermometer, you can measure how hot your garage is getting and staying to determine if air conditioning might be in order. For more expensive items, such as classic cars, choosing to install air conditioning might be a no-brainer.

Other than parking our cars, garages are commonly used as shops, crafting areas, and workout gyms. If you find that your garage is just too hot for too long to take advantage of these uses, air conditioning is probably a good call.

However, the decision to air condition a garage is case by case. For instance, perhaps the heat only makes the garage unusable for a few hours a day during the summer. Maybe in this situation, you will just tolerate the hot summer months and plan your daily schedule accordingly.

Your Budget

Depending on the size of your garage, the current level of insulation, and the number of air conditioning days in your region. air conditioning in your garage can be relatively cheap to very expensive.

Make sure that air conditioning is within your budget before investing money into this endeavor. The following sections include more information about the cost of air conditioning in a garage.

New Construction or Remodel

The considerations for air conditioning in your garage are similar for new construction and remodels. However, adding air conditioning to new construction is cheaper per square foot of cooled area when compared to adding AC after the fact.

When deciding to add AC to new construction, consult neighbors and local building experts for region-specific information. Asking experienced locals is also a wise choice for a remodel garage AC.

Advantages of Garage Air Conditioning

The main pros of garage air conditioning are that it makes the space more usable and comfortable. In addition, if you air condition your garage, it means less hot air will transfer to your home through the adjacent wall. In turn, your in-home AC will not need to work quite so hard.

Disadvantages of Garage Air Conditioning

The primary cons of garage air conditioning involve the additional labor and cost of this project. Depending on the type, air conditioning units can be relatively affordable. However, the additional insulation required to make that unit run efficiently can quickly become costly.

Also, keep in mind that air conditioning a garage with a window-mounted or portable AC unit requires installing and removing the unit every season.

Insulated garage attached to new single family residence

Finally, air conditioning is not free. For each cubic foot of air in your garage, you will need to pay an increased electricity bill as your garage air conditioner works harder. While insulating your garage does cost more upfront, it will save on the electrical bill down the line.

How to Install Garage Air Conditioning

Before making the decision to install garage air conditioning, it is nice to know what exactly you are getting into. In general, the steps are as follows. First, choose the right type of AC unit. This means an appliance that both fits your needs in form and capacity.

Next, you will need to consider insulating the garage. This includes the walls, ceiling, and garage door. Finally, you may need to modify the garage or a garage window in some way to accommodate your new AC unit.

How NOT to Cool a Garage

It is often tempting to add a vent from your central cooling system that points into your garage as a means to cool that space. However, this is a very bad idea.

First of all, your central AC system is designed for a certain capacity. Adding the load of the garage will overtax the system and end up costing you more than simply buying a separate system.

Also, by having a vent in your garage that leads to the living space, you run the risk of pulling harmful chemicals and exhaust gases from your garage into the home (including carbon monoxide).

The risk of this harmful back drafting is low, but the consequences can be sickness and even death.

Finally, there is usually no intake vent in your garage. This means that the outflow of your central AC system will exceed the inflow. To make up for this, your system will end up sucking hot air in from outside. This forces your AC unit to work much harder, which costs you more money in the long run.

What is the best way to cool down a garage?

In this section, we discuss the types of AC units appropriate for a garage. These include window mount units, portable wheeled units, and mini-split ductless heat pumps.

Window Mount AC Units

Click here for a window mount AC unit from Amazon.

If your garage has a window, a window mount AC unit may be just the ticket. These stand-alone units are placed in a window, allowing them to exhaust the heat outside the garage.

Before settling on this type of air conditioner, make sure that your window will fit a large enough unit to efficiently cool the space. Usually, people use formed poly insulation to block off any window space that is left open. Simply buy a large piece of insulation board and cut it to fit the remaining window space.

Portable Wheeled AC Units

Click here for a portable AC unit from Amazon.

These portable units come in many sizes and are easy to move on their wheeled base. However, they do require some sort of air outlet. This can take the form of a small window but may require the additional work of installing a special vent area in the wall of your garage.

Industrial Portable Units

Many portable AC units are built for professional garage and warehouse settings. These units are built much sturdier and are designed to filter out more caustic and consistent material. For this reason, springing for an industrial unit may be appropriate, depending on the type of use your garage sees.

Mini-Split Ductless Heat Pumps

Click here for a mini-split on Amazon.

Mini-split systems are very energy efficient but come with a much larger price tag. These units are more appropriate for large garages.

Further, mini-split systems also function to heat the space which is great for regions that have significant heating and cooling seasons. Take note, these types of systems require a licensed AC professional for installation.

How big of an air conditioner do I need for my garage?

A good metric is that you need 20 BTU of output per square foot. For example, a 20-foot by 20-foot garage has a grand total size of 400 square feet. Multiply 400 by 20 to get 8,000 BTUs.

This means that a 400 square foot garage requires an AC unit that is at least 8,000 BTUs (or larger). However, this BTU recommendation assumes decent insulation levels. For uninsulated garages, you may need a much larger air conditioning unit.

What is a good temperature for a garage?

In short, a good temperature for a garage is one that is both comfortable and keeps all your belongings in good condition. Generally, the exact temperature changes from person to person. However, any garage that is below 80 degrees Fahrenheit and above 40 degrees Fahrenheit is a good temperature.

Is a hot garage dangerous?

A hot garage can in fact be dangerous. First of all, working out or working in a hot garage can lead to heat exhaustion and heatstroke. If untreated, these conditions can be very dangerous and even life-threatening. If you do not have a good way to cool your garage in the summer, perhaps limit your time there to the cooler evenings and nights.

How to Insulate a Garage?

Air conditioning in an uninsulated garage will have to work very hard for limited results. The cold air produced by your air conditioner will seep out through the walls, door, and ceiling. To avoid this, take the time to properly insulate your garage.

To learn the exact cost of insulating your garage, research wall, ceiling, and garage door insulation in your area, or take the time to get a quote from an insulation professional. To start your research, read these great articles from HVAC Seer to learn about insulating your garage:

Can a mini-split cool a garage?

As mentioned above, a mini-split is a very efficient way to cool a garage. In addition, mini-split heat pumps can also be used to heat a garage in the winter! The downside of these appliances is their large upfront cost.

How much does it cost to air condition a garage?

The cost of running an air conditioner depends on the size of your garage, the efficiency of the unit, and the level of garage insulation. This means that the actual cost can vary greatly from garage to garage. However, and generally speaking, air conditions costs between $0.06 and $0.88 per hour to run.

In Closing

In this post, we answered the question of whether or not you should air condition your garage. We include the pros, cons, and how-tos of this question. With all this information, you can now make an informed decision regarding installing an air conditioner in your garage! Good luck!

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