A repair shop, workshop, man cave, or garage is traditionally the place to park your car. However, the typical garage is not just for cars anymore. And, a lot of people prefer to park their vehicles in the driveway. No car in the garage creates an untapped goldmine of additional space.

Think about the endless possibilities and a wide range of uses that your garage can offer. For some people, it is an additional storage space, workshop, a home office, or even a gym. If your garage doubles up as your workshop, then chances are you probably spend a lot of your time in there. It becomes challenging to work during the hot summer months if your garage does not have a cooling system.

Generally, without air conditioning and insulation, your garage’s temperatures can soar up to 10 degrees higher than the outside temperatures. In the hot summer months, that’s a lot of sweltering heat that will slow you down and make it impossible to carry out your daily tasks.

Whether you are dealing with a humid climate or just plain dry heat, it may be the right time for you to consider some garage/ workshop cooling solutions. Most people wonder, why does the garage get so hot? What is the right size to install in the workshop/garage?  If, for example, you use a portable air cooler in your shop then you need to know how to vent it properly?

repair shop working in garage


Here are a few reasons why your shop may get so hot:

  • Your garage is not insulated
  • Darker garage colors will conduct heat, and brick walls absorb heat.
  • West-facing garages are exposed to the late afternoon sun’s blaze
  • Your garage may not have any ventilation system
  • Small windows or windowless garages can be hotter
  • Parking your car in the garage immediately after using it – your car will radiate heat raising your garage’s temperature.

Reasons to Install a Cooling System in your Garage


The primary reason to install an AC in your garage is to keep the space cool and create a comfortable working environment. If you spend a lot of time in your garage, it is wise to look for a comprehensive and more permanent cooling solution. Working in a sweltering and humid environment is less than ideal, and it may affect your productivity.

If you use your garage to store valuables (collector cars) or materials that are heat sensitive, then you should consider installing a cooling system in there. This will keep your stored goods in good condition by reducing stuffiness, mold, and mildew even during the hottest months of the year.

Lastly, air conditioning your garage could help you with your overall energy costs. When the garage is poorly ventilated and lacks a cooling system, it gets hot. This warm air in the garage rises to the rooms above it or adjacent rooms as well. A cooler garage ensures that your house’s central AC system doesn’t have to work extra hard to keep the indoor temperatures low.

Options For Cooling Your Work Shop Space

wall AC unit


There are many ways to keep your garage cooler even during the hottest of months. Some of these options are only temporary and will provide temporary relief. Others are more permanent, and while they could be a bit more costly, they will provide permanent relief from the sweltering heat and humid air.

For instance, keeping the garage door and window open will provide a breath of fresh air, but this can only do so much. Using a portable fan or even installing a ceiling fan is a cheap way to get the air in your garage space moving. This is also not a permanent solution as oscillating fans simply create airflow in your garage giving you a little bit of relief from the heat. A humidifier will also offer a bit of relief and make it more comfortable to work from your garage.

With this in mind, it is easy to see why more people are opting for more effective cooling systems; air conditioning units.

Things to Consider when Choosing an AC Unit for your Garage or Work Shop

First things first, if you are going to put an air conditioner in your garage then, you must ensure that the garage is well insulated. This can be added on the garage door or within the walls. Without insulation, your AC unit will be forced to work harder than it ordinarily should. Insulation will make your air conditioner more effective and avoid wasting energy and money.

Keep the following in mind when looking for an air conditioner for your garage.

1. Size matters

Calculate the correct size for an AC unit that is capable of conditioning your entire garage space whether you settle for a portable unit or otherwise. Compare your garage’s square footage with the unit’s BTU rating to select one that is suitable.

It’s advisable to buy a unit with a higher BTU rating for your garage because most garages have little insulation, lots of open space and higher temperatures. This way, your unit will do the job faster with little strain on itself.

2. Ventilation

Your air conditioner will need a vent – venting an AC is necessary as the unit needs a channel to release the hot air. This could be a window, an exterior wall or the garage door. Windowless garages will require you to cut a small hole in the exterior wall to vent your AC unit. A properly installed vent ensures that the hot air can travel from the unit through the vent and out of your garage – this facilitates effective cooling.

3. Location

Depending on your location, you may need to buy a dehumidifier or an AC that come with dehumidifying capabilities. This will be a great addition as it will make your garage a more comfortable place to work in. A dehumidifier for your garage can have year-round benefits.

4. Compact, Powerful, Multi-modes

Look for an AC that is compact – it will take up less space leaving you with enough floor space for your workshop. Looking at the physical size of a unit is not enough you need to make sure it can handle the square footage of your space. This will help bring down the temperatures to a bearable level helping you work without much trouble. They can cut through the summer heat especially if your garage is not properly insulated. An AC with multiple modes will be of great help once the summer months are over. Areas that get warm during summers almost certainly get cold during winter. An AC with a heat mode will come in handy during winter as you will not have to buy a heater.


working in shop

Selecting the Right Unit

Now that you have already decided to install an air conditioner in your garage let’s get down to the interesting part – choosing a unit that is most suitable for your garage. The fact that you are looking for a unit that will only serve your garage makes this decision easier to make. There are different types of air conditioners, and each has its pros and cons.

1. Portable Air Conditioners

Portable Air Conditioners have a greater advantage over window units because they can be used in a garage that has no windows. It stands on

its own and is effective in cooling a moderately large space with ease. However, bear in mind that an AC unit will be a total waste of money and energy if your garage is not well insulated.

Portable units, like other air conditioning units, need a vent. In a windowless garage, you will need to install a vent that goes through the exterior wall or the garage door. Most units come with a hose to vent to the outdoors.

It is advisable to buy a powerful unit with a high BTU if your garage temperatures usually go above 35 degrees centigrade. This way, your unit will be able to handle the task without burning out quickly. Remember that correct installation is key in ensuring your AC unit works properly and safely.

2. Window Air Conditioners

As the name suggests, you will need a window to mount one of these. Or a relatively big hole in the wall. Window ACs are relatively cheap and easy to install. Additionally, they work well in a sealed and insulated space meaning you can shut the garage door and still enjoy a cool working environment.

Another advantage of the window AC is that they do not take up floor space. This is a plus for a garage that has little floor space. They have directional louvers that allow you to direct cool air to a specific area. So you can get cool air coming right where your working station is at. Although they are somewhat bulky, they are a great option regarding affordability and effectiveness.

3. Mini-Split Air Conditioners

This is yet another option that you should consider. They are much like your standard home HVAC system, but compact and with no ductwork. This type of AC has two components – an indoor unit and an outdoor one. They are quickly becoming popular as they can be placed pretty much anywhere.

You will need an outside wall for the outside condenser while the indoor component - which usually occupies about a quarter of the size a typical unit would take – will be on the other side of the wall. They make an appealing option because they are known to be very energy efficient and they don’t take up floor space.

The downside – Mini-split ACs are usually much more expensive to buy. You will also need a certified HVAC professional to install and mount the unit for you. To get the true efficiency and saving benefits of these units, you will have to properly insulate your garage.

4. Dehumidifiers

This is not a cooling solution for your garage but rather, something necessary to make working in your garage a bit more bearable.

Dehumidifiers help remove moisture from the air – high levels of humidity in your garage can make space feel much hotter than it is. Dehumidifiers reduce relative humidity making your workspace feel much cooler. They can be used all year round in humid areas, they are portable, cost-effective and can be used with other cooling systems in your garage. It makes a great impermanent addition to your garage cooling system.  You do need to plan on how to handle the water that is taken out of the humid air, make sure to drain it properly.

Safety Precaution

Experts advise that if you really have to air condition your garage, then you must get a separate system for the garage only. Most people would be tempted to extend their central air conditioning to the garage because it’s cheaper and it seems like the logical thing to do. Experts caution against this; there is a right way to air condition your garage and a wrong way. Tapping into the central system is an absolutely wrong idea. Here is why;

1. Poor Indoor Air Quality

An air conditioner needs to be balanced in its air flow. For instance, a 2 ton AC pulls 800 cfm (cubic feet per minute) of air from a room or space and puts back 800 cfm of air back into that space. Without an air return back into the central air conditioning system, a central duct extension will upset this air flow balance such that if 800 cfm is being pulled out, only 400 cfm will be getting in. This will depressurize your house and allow outdoor air (which is coming in to fill the deficit) to bypass your HVAC filter system. Pollutants will most likely build up inside the house causing poor indoor air quality.

2. Back drafting

The AC could be pulling air down the flue and this means that exhaust fumes aren’t being expelled as they should. These potentially fatal fumes such as carbon monoxide, could find their way into the house and cause devastating effects to the people and pets living inside. As the garage is essentially used as a storage room for many households, things like paints, adhesives and other chemical fumes may also find their way into the house.

It is for these reasons that precaution needs to be taken when installing an AC system in your garage. Preferably, get a certified professional to deal with all the installation work. If you have to install it yourself, do it the right way. There is no room for errors.