Most people don’t give the ventilation in their garages a second thought – focusing more on other parts of their houses. Making sure your garage is well-ventilated is essential, however. 

Otherwise, it could lead to a host of problems down the line.


Why Is It Crucial to Ventilate Your Garage?

Your garage is where you do most of your DIY home improvement projects, and it is where you park your car. These activities release fumes hazardous to your health into the air, and they tend to linger in your garage if it is poorly ventilated. 

There is a risk of these dangerous fumes entering your home contaminating the air inside your house.

Having a well-ventilated garage also keeps the temperature cool and reduces humidity. 

Not only does this keep you comfortable while you’re working in your garage, but a garage with less moisture means mold can’t grow. Mold is a health hazard and can ruin surfaces where they grow.

Without proper ventilation in your garage, temperatures can get between 10 to 18°F hotter than outside. If the temperature gets too hot in your garage, it could damage items you’re storing in it, such as paint and electronics.


How Does Ventilation Work?

Ventilation is when clean air is brought into a space. That clean air is either mixed in with the air currently in that space, called mixing or dilution ventilation, or the clean air replaces the air currently in that space, called displacement or piston flow ventilation.

How to Ventilate an Attached Garage

Legally, you are not required to ventilate your garage. However, the Environmental Protection Agency (EPA) recommends ventilating your garage to rid it of carbon monoxide and other toxic fumes. 

For residential attached garages, they recommend using a 100 CFM ducted or 80 CFM un-ducted fan for this purpose. 

The usual way to ventilate your attached garage is to install an exhaust fan. First, start measuring how large your garage is so you know what type of exhaust fan kit you should buy. 

Once you get the dimensions of your garage, buy a self-installation exhaust fan kit that has enough power to ventilate a garage as large as yours. 

We will discuss tips on how to install your exhaust fan in the section below.

How to Ventilate a Detached Garage

There is less urgency in ventilating a detached garage because there is no risk of hazardous fumes and carbon monoxide seeping into living areas of the house. 

However, you may still consider it as a way to cool down your garage, especially if you do a lot of work in your garage.

There are several ways to ventilate your detached garage:

  • Install windows
  • Place a window fan
  • Install vents
  • Install an exhaust fan

We will go into more detail for each one of these methods further below.


Garage Ventilation Options

There are several ways to improve your garage’s ventilation.

Exhaust Fans

Exhaust fans draw clean air from outside to circulate into your garage. They are installed in your garage walls and have grilles to let the air in.

Putting an exhaust fan in your garage also keeps a slightly low pressure, keeping the fumes inside the garage instead of seeping into your home through cracks. 

It helps cool down your garage
A quieter option compared to others such as blower fans
Pushes out harmful toxins from your garage
Installation may be complicated if you’re doing it yourself, especially
Instructions that come in exhaust fan kits may not be clear
There is a limit to how much an exhaust fan can do. If your garage faces west or south, for example, your garage can remain unbearably hot even with an exhaust fan because it’s facing the sun directly.

How to Install an Exhaust Fan

If you decide to install your garage exhaust fan yourself, here are a few tips to follow to make sure you install it correctly.

  1. Measure your exhaust fan and cut a hole in your garage’s ceiling so that the exhaust fan will fit snugly in the hole.
  2. Switch off the power in your garage.
  3. Run wires from the hole for your exhaust fan to the nearest junction box.
  4. Cut the wires with wire cutters to make sure they’re the correct length. You can now install the fan.
  5. Connect the fan to the exhaust hose. Push the exhaust hose through the roof.
  6. Fasten the exhaust fan to the roof with brackets. These should be included in the kit you purchased.
  7. Screw the fan into the wall and connect the wires.
  8. Seal any gaps around the casing that you see with caulk.
  9. Turn on the power in your garage and check if the fan works.

Floor Fans

The fan you use for your kitchen or bedroom is different from the one you use in your garage. The ones for a garage are built to move enough air over a large area and should be able to withstand harsh environmental conditions.

If you have windows in your garage, putting a floor fan in front of an open window can work wonders in cooling your garage.

You can quickly move the fan from one spot to another
You can adjust the speeds on many floor fans
It takes up floor space
Noisy

Wall-Mounted Fans

Wall-mounted fans save you floor space and keep it out of the way. In addition, it accumulates less dust since they’re further from the floor.

It circulates air through the whole garage
It provides a different airflow angle
It saves floor space
More complicated to install
Once installed, it limits where the fan is, unlike floor fans that can move from place to place
Noisy

How to Install a Wall-Mounted Fan

If you decide to install your garage exhaust fan yourself, here are a few tips to follow to make sure you install it correctly.

  1. Ensure your new fan comes with the mounting hardware and necessary brackets
  2. Check how much clearance above the floor and from the ceiling you need. 
  3. Assemble the fan, starting with attaching the rear and front guards.
  4. Find a stud on the wall where you can install the mounting plate
  5. Look for a location near a power outlet, and make sure you install it at an appropriate height
  6. After securing the mounting plate, attach the mounting bracket and insert the fan into the frame.

How to Choose the Best Fan for Your Garage

There are many different types of fans for your garage available on the market to choose from. However, it would be best if you considered the following when purchasing a garage fan:

  • CFM: The higher the CFM rating, the more airflow it produces, cooling down your garage faster. How many CFMs your fan should have would depend on how large your garage is. A smaller garage doesn’t need a high CFM for its fan to cool it sufficiently. 
  • Type of Fan: There are different types of fans to choose from as well: wall-mounted, blower, or ceiling fans
  • Materials Used: For your garage, buy a fan with metal blades as these are heavier-duty – metal fares better under different environmental conditions and are sturdier. Metal blades are also more efficient at circulating air.

Ventilation System

If your garage doesn’t have any windows, you can install vents instead. Vents bring air in from the outside – compared to an exhaust fan which removes indoor air to the outside. 

Vents should be placed up high on your garage walls or on the roof so that the warm air that ascends to the top of the garage can be released by the vents, keeping your garage cooler.

Reduces indoor air pollution levels
Cheaper than other options
Balances the temperature in your garage
If your vent is the kind that remains open all the time, it may not be the best choice if you live in a place that has snow
Installation may be a challenge
It may leak when there is heavy rain

How to Install a Roof Vent

Here are a few tips on how to install a roof vent. Plastic or metal vents are available for purchase at most hardware stores. 

  1. Make sure you have someone assisting you while installing the vent, as you will be spending a lot of time on a ladder and need help getting tools and such.
  2. Place the vent as high as possible on the exterior garage wall – high enough that the cool air can enter and warm air can move out.
  3. Measure your vent, then cut holes for it using a circular saw.
  4. Finally, insert it from the outer part to ensure it fits properly.
  5. Seal any gaps with caulk to prevent water from coming into your garage when it rains.
Today’s Homeowner Tips

Usually, one vent is sufficient for a garage, but you have to make sure it’s large enough. If there isn’t one available that’s large enough, you can buy a few small ones.


Other Ways to Keep Your Garage Cool

Aside from the above, there are other ways to keep your garage cool:

  • Concrete or stone pavement for your garage floor
  • Installing a man door
  • Insulated window inserts in your garage door
  • Non-insulated garage doors
  • Paint the Garage Door to a Lighter Color
  • Avoid Using Tools that Uses Electricity and Generates Heat Inside Your Garage
  • Install an Air Conditioner
  • Seal Any Gaps in Your Garage
  • Use a Dehumidifier
  • Remove Clutter

How to Ventilate a Garage that Doesn’t Have Windows

Ventilating a garage with no windows is a challenge but not impossible. Here are some options available for you:

  • Open the garage door
  • Buy a fan for your garage
  • Use a humidifier
  • Build a swamp cooler
  • Use an air conditioner
  • Install a vent

Editorial Contributors
avatar for Matt Greenfield

Matt Greenfield

Matt Greenfield is an experienced writer specializing in home improvement topics. He has a passion for educating and empowering homeowners to make informed decisions about their properties. Matt's writing focuses on a range of topics, including windows, flooring, HVAC, and construction materials. With a background in construction and home renovation, Matt is well-versed in the latest trends and techniques in the industry. His articles offer practical advice and expert insights that help readers tackle their home improvement projects with confidence. Whether you're a DIY enthusiast or a seasoned professional, Matt's writing is sure to provide valuable guidance and inspiration.

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