How to Cool a Garage with No Windows

By | May 5, 2023

How to Cool a Garage with No Windows
Garages can get hot in the summer and don’t usually have a window to let air blow in or install a window air conditioner unit.

Cooling a windowless building such as a garage can be done in different ways, depending on the scenario.

Options can vary from low-cost, budget-friendly to higher-cost and more involved installation.

With that in mind, below are the top ways to keep your garage cool on hot summer days.

5 Best Ways to Cool a Garage with No Windows

  1. Ceiling Fan
  2. Cool a Garage with No Windows Ceiling Fan
    A ceiling fan may not help to cool a garage down much, but can move air which can add some comfort.

    If you are looking to cool things down, then an air conditioner or evaporative cooler is a better option.

    Ceiling fans can often be used with other options to help move air about, which can keep the entire garage at an even temperature.

  3. Evaporative Swamp Cooler
  4. Best Ways to Cool a Garage with No Windows Swamp Cooler
    Evaporative swamp coolers work very well in dry climates and are low-cost to operate.

    The only downside to a swamp cooler is they do not work when the humidity level is high.

    They are very common in the American Southwest but almost nonexistent in southern states.

    If you live in a very dry climate, a swamp cooler is a very good option, but if you live in a humid climate, another option will need to be found.

    A hole will need to be cut in the garage to install a unit as well as a water line run.

    There are many types of swamp coolers with the main options, including a downdraft and side-draft.

    Downdraft blows the air downwards and is good for a roof-mounted unit.

    Side draft blows the air sideways and is the most commonly used unit in garages.

    Read here for more on swamp coolers.

  5. Mini Split
  6. Best Ways to Cool a Garage with No Windows Mini Split
    Mini Split units are by far the best option but also cost the most.

    The units are very efficient, making them low-cost to operate and the heat pump version can cool and heat.

    Low-cost units can cost roughly $900-$1300 for a do-it-yourself kit.

    If you install a unit yourself, some basic HVAC tools will also be needed, which can add another $80-$90.

    To install a unit, a 2-3 inch hole will need to be cut into a wall to run the refrigerant line set.

    Electrical will also be needed, along with pumping down the system with a vacuum pump.

    Hiring an HVAC company to install a unit can also be done but will cost much more, ranging between $3000-$5000.

    Installing a unit does require a handy type of person, but many DIY individuals install them.

    If you go this route, be sure to watch some YouTube mini split installation videos first.

  7. Through the Wall AC Unit
  8. Best Ways to Cool a Garage with No Windows Swamp Cooler Through the Wall AC Unit
    While most window AC units are mounted in a window, a sleeve can also the installed for it to fit into.

    This is very common when no window is available, but a low-cost window air conditioner needs to be installed.

    It does require cutting a hole in the wall for the air conditioner to fit into, which can be a pain.

    While more difficult than fitting it into a window, it does work and is a straightforward job.

    There are specific air conditioners built to fit into a wall.

    Read here for more on through-the-wall AC units.

  9. Portable AC Unit
  10. Best Ways to Cool a Garage with No Windows Portable AC Unit
    A Portable AC unit can also be used and also work well when the right size is used.

    Portable units have both air conditioner and evaporative units.

    The AC units will have a 5-7 inch hose that is sent outside and pump hot air outside.
    Best Ways to Cool a Garage with No Windows PORTABLE AC
    A 5-7 inch hole is needed to send the hot air outside.

    The hole can be cut into the roof and the hot air sent into the attic, which is sometimes a good option.

    Evaporative units can also work well but only when the air is dry.

    Read Here for more on the best portable AC units for a windowless garage.

Will a Portable AC Unit Cool a Garage?

A correctly sized portable AC unit can cool a garage.

AC units are rated in BTU capacity for how much cooling power they have.

The BTU capacity is sized by the square footage of space.

For example, a 20 X 20 garage is 400 square feet which is matched to a 10,000 BTU unit.

How Do You Vent a Portable Air Conditioner in a Garage with No Windows?

A hole is usually cut into a wall but can also be cut into the ceiling.

The hot air will be pumped out through a hose going out the hole.

While a wall can be cut open to fit the hose out, the ceiling is often a better option since it is usually just sheetrock.

How Do I Remove Hot Air From my Garage?

The main way to remove hot air is to use an air conditioner or evaporative cooler.

A large fan can also work to blow out hot air but will not cool.

Cooling units come in all shapes and sizes, including portable models.

Getting the right-sized unit that fits into the garage will be the best way to remove the hot air.

Will a Swamp Cooler Work in a Garage?

Yes, an evaporative swamp cooler will work in a garage as long as the climate is dry.

If the climate is humid, swamp coolers do not work and basically become large fans.

Keep in mind even dry climates will have rainy or humid days.

Can You Cool an Uninsulated Garage?

Yes, an uninsulated garage can be cooled with a swamp cooler, which is the best option as long as the climate is dry.

A swamp cooler needs to cycle air, so insulation is less of a factor compared to air conditioning.

Of course, a swamp cooler will only work when the air is hot and dry.

Air conditioning can also be used, but the cost to operate it will be higher compared to an insulated space.

There are many options for cooling a garage with all shapes and sizes of cooling units.

The main technology used to cool a garage is an air conditioner or swamp cooler.

If you live in a dry climate, a swamp cooler or air conditioner is a good option.

If you live in a humid environment, an air conditioner is the best option.

The units can also be fixed and fitted for the garage or portable.

Have you cooled down in a hot garage? What is the best method you have found? Let us know in the comments below.

Category: HVAC how to

About Aaron H. Benetti

Aaron H. Benetti an HVAC technician who has worked in the field since 1991. He began his career as an HVAC installer and later began doing troubleshooting and repairs. Around 2010, he began to write books on HVAC topics, mainly tutorials and how-to information. Currently, Aaron works as an HVAC tech and also writes many articles and posts for websites as well as books and videos on HVAC topics.

One thought on “How to Cool a Garage with No Windows

  1. Becks

    I have 2 window ac units. I have windows in the garage door. But can’t permanently put it there. Too thin and units too heavy . Plus I open my garage. I am also in a rental and cannot make holes in wall. Do you have a suggestion on how to funnel hot air out?. How to mount etc?


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