Using a Portable AC in the Garage: Good or Bad Idea?

The garage serves a lot of purposes in every household. Aside from providing a space where you can park your car, it is also a perfect spot to get your work done or an area where you can gather your family or host a party at home. Unfortunately, when the summer hits, it tends to feel hotter inside, causing you to avoid staying in the garage during this time.

Using a portable AC in the garage is one of the most common ideas to cool it down in scorching weather. It may not always be the best option, but installing it can still be good. You can make it work in your garage after considering several factors and developing a plan.

If you plan to have a portable AC unit in your garage, you need to do your research first on how you can install one. It is a lot of work, and there are also many things you should consider. Hence, we give you some essential tips you should know before installing a portable AC unit in your garage.

Why are Garages so Hot?

Almost empty garage

Garages are generally hot, but they get hotter like saunas, especially in the summer. The two common reasons for the high temperature in garages, similar to other rooms in the house, are ventilation and insulation. But apart from these, other factors contribute to the intense heat of garages.


In any room, poor insulation often results in warmer temperatures. For example, providing insulation in garages gives resistance to heat flow and prevents the cold air from escaping out of the room.


Many rooms in the house may suffer from poor ventilation. But it can be worse in garages since they are enclosed and lack windows. If there is no proper air circulation, the garage will undoubtedly suffer from intense heat and cause discomfort once you enter it.


The location of your garage also plays a vital role in why it gets hot. You might need to get a compass with you to know the direction of your garage. For example, if your garage is facing south or west, you might want to avoid staying in it from noon until the late afternoon since the sunlight directly hits it.


Many people do not know about this fact, but colors also affect the internal temperature of a room. For example, if your garage has darker colors on its walls and ceilings, it absorbs more heat.

Parking the Car Right After Driving

Lastly, parking the car right after using it will also contribute to the increasing heat inside the garage. Try to cool the engine first for several minutes before parking it inside.

Avoiding all these factors can make the garage cooler. But to maintain the desired temperature, installing an air conditioner unit is a good solution. But can it also work in garages?

Can You Air Condition a Garage?

Yes, you can air condition a garage. Since garages serve many purposes, mainly for storage, keeping them cool is ideal for protecting different objects that can get damaged because of intense heat.

Also, if you spend more hours in the garage to work, you want to feel more comfortable inside it. However, many people commit mistakes when installing an AC unit in their garage.

Common Mistake When Installing an AC Unit in the Garage

To cool down a garage, many people tend to make rash or poor decisions about installing air conditioners in their garage without knowing the harmful effects it may cause.

Since the garage is a place where you store other chemical materials like paints, pesticides, and gasoline, their fumes may get into the ductwork of your home’s AC system and spread into the entire house.

Though there are ways to prevent it from happening, it is not an easy process to do. You might even violate a particular housing inspector’s code because of this idea.

But even if you manage to install an air conditioning unit in your garage, you may still experience hot air inside. That is why aside from air conditioning, proper insulation is also one of the things you need to work out.

Prioritize Insulation When Installing an AC Unit in the Garage

Most garages do not have insulation, so the garage will remain hot even if you use the most powerful air conditioning unit. 

Before putting an AC unit in your garage, ensure the garage’s walls, ceilings, and doors are well insulated. It will keep the cool temperature coming out of the AC unit and maintain the temperature inside.

However, different types of AC units require specific usage and installation. So how can you take advantage of using a portable AC unit in your garage?

Can You Use a Portable AC Unit in a Garage?

Portable AC units are, in fact, a much better option than other types of AC units you can install in your garage, though some people consider them as the last option to cool down a room because they believe it is less efficient and effective.

With good planning and strategy, a portable AC unit is enough to reduce the temperature of your garage, especially if it is not too big. You can also decide to partner it with other HVAC units like a mini-split aircon and exhaust fan for better cooling, airflow, and ventilation.

Portable AC units are a better option for those who cannot afford to buy more expensive AC units, such as split-type aircon. So if one of your primary concerns about installing air conditioning in your garage is budget, then definitely, a portable AC unit will work fine for your needs.

Factors to Consider When Using Portable AC Unit in a Garage

Now that you know it is possible to use a portable AC unit in a garage, here are several factors to make it work well in your garage.


The first thing you need to find out is the BTU, short for the British Thermal Unit, the international energy measure unit. BTU refers to the amount of heat an AC unit can produce in a room within an hour for air conditioning. It means that the aircon’s BTU will depend on the size of the room where you will use it.

Before buying a portable AC unit, checking on the BTU will let you manage to lower the temperature in the garage once you use one inside. Thus, you do not need to buy a more extensive and more expensive unit with a higher BTU if your garage is not too spacious.

A typical portable AC unit has a BTU range of 8,000 to 25,000. Therefore, a two-car garage will need to have at least 12,000 BTU of aircon unit for a cooler temperature.


Aside from the BTU, it would help if you also considered the climate in your area. If it gets too hot, especially during the summer, you may need to buy a larger portable AC unit. But if you do not often spend a lot of time in your garage, a smaller one is enough to compensate for the heat inside.

Installing Windows and Exhaust Fans for Ventilation

Proper ventilation is also necessary to help the portable aircon unit do its job. As mentioned, windows play a vital role in better airflow. If your garage does not have one, you might consider drilling a hole in the ceiling or the walls of your garage or installing an exhaust fan.

If it is not possible, creating a small opening in the doorway will allow the cold air to come out and replace it with the fresh air from the outside. If you fail to work on the ventilation of your garage, it can result in indoor air pollution.

Check Other Essential Features

You may want to consider other features when buying a portable AC unit. For example, you can choose one with a timer or remote control for your convenience and to save energy.

A lighter portable AC unit also works fine since you can quickly move it inside the garage. You can also check other units with a built-in dehumidifier, so you will not need to buy a separate one.

What Size of Portable AC do You Need for a Garage?

Air conditioner mobile for room

The size of your garage depends on the size of the portable AC unit you need to buy. You do not need to spend a lot for a bigger AC unit with a bigger BTU if you only have a small space inside.

You need to ensure that the portable AC unit will fit in your garage, so there is also more space left you can use for other stuff.

How Do You Install a Portable Air Conditioner in Your Garage?

Now, let’s move on to the exciting part: installing the portable air conditioner unit in your garage. It is easy to install the unit in your garage as long as you have the right tools and materials.

  1. Choose an Ideal Location: Some factors you can consider to help you decide are the area where you mostly spend your time in the garage or the part where it is mostly hot.
  1. Find a Nearby Outlet: You need a nearby outlet for the power source, so you do not need to use an extension cord. In this way, your workspace inside the garage is free of any obstacles. For example, people trip over because of poor cable management or accidentally plug the unit from its power source.
  1. Drill a Hole: It will serve as a space where you can put the hose for heat exhaustion, so there is a pathway for the hot air to escape the room. The process requires you to do accurate measurements so that the hose can fit well and there will be no gaps.
  1. Plug and Play: Once you finish attaching the hose for the heat exhaustion, you can now connect it to the portable AC unit. Try to plug it into the nearby outlet and check if it can cool down the garage. Adjust the settings of the unit as needed.

To End

And there you have it. You finally have a portable AC unit in your garage! You can now spend as much time working in your garage or conducting social activities without worrying about the heat. But make sure you also perform regular maintenance and cleaning to keep the quality and performance of your portable AC unit.