How to Cool Down Your Garage During the Summer

Why does your garage get so hot?  For a lot of older homes, garages were tacked on to obtain extra storage space or to keep vehicles. Of course, this was years prior to the days of modern and massive SUVs.

Because Americans now use garages for sprawling projects, lawncare machinery, and an average of at least two vehicles, the shortcomings of older garages have become more apparent than ever.  Most were built without ventilation systems or insulation, which is why so many garages are freezing cold in the winter and blazing hot in the summer.

If you have an older garage that struggles to keep out the heat, there are plenty of modern inventions and methods to keep it cool in the summer.

Fans: The Cheap & Easy Solution

Cooling your garage is as simple as adding an inexpensive window fan. Sticking a fan in your garage’s window and blowing the hot air out is an effective method to lower the temperature.  Even better: add another fan to help promote air circulation so there’s a constant breeze flowing through your garage.

If you’re feeling fancy, you can get a high powered shop fan to really crank out the hot air, but a simple oscillating household fan will also do the trick.  Ideally, use windows that are across from each other to push and pull the air for optimal ventilation.

Ventilation Systems

Installing ventilation systems can be tremendously helpful in promoting airflow and cooling your garage in the summertime.  Passive ventilation systems are usually installed on the roof of the garage, using very little energy consumption to dissipate the heat from the garage attic.  The most common passive ventilation systems are spinning turbine roof vents.

Active ventilation systems are more complex and therefore more expensive, but these systems are superior in their effectiveness at expelling hot air because they are mechanically powered.  Active ventilation systems are typically installed by a professional and are mounted on the roof or within the garage’s walls.

Air Conditioning: Effective but Pricey

The problem you’ll run into with fans is that while the air circulation is pleasant and helps push heat out of the garage, fans don’t actually make the internal temperature of the garage cooler.  Air conditioning, alternatively, will do this, but it comes at a price.  AC units require an upfront investment and an expense to run.  Getting a window AC unit is your best bet—you’ll want to avoid tapping into your main house’s AC system to cool the garage.  There are too many dangerous fumes and with the unlikely event your garage has a HVAC system return vent, these fumes can find their way back into your house.  Connecting the ductwork from your main AC system to the garage can also change the pressure within your home and ultimately, pollutants and allergens will begin to fester.

Cooling Down Your Garage

So, getting a smaller, separate AC unit is the way to go, but you’ll want to consider its size in comparison to the size of the garage.  A typical two-car garage is around 20-feet wide by 20-feet deep, so this 400 square-foot space will need 9,000-10,000 BTU AC unit.  You can also use an online BTU calculator to determine your AC unit needs.

Insulation Matters

Another easy and cost-effective cooling method is to install insulation.  Most homeowners associate insulation with keeping heat inside, however insulation’s purpose is actually to regulate temperatures.  This means that even in the hot summer months, insulation will work to mitigate heat and keep your garage’s internal temperature nice and cool.  Installing insulation can be done by even the most inexperienced do-it-yourselfer.

Small Steps to a Cooler Garage

A few other small steps you can take to help cool your garage this summer are:

  • Park your car outside:  If you’re using the garage for an afternoon, park your recently driven car outside.  The car will still have a hot engine, even from a short jaunt to the store, and by parking it outside you can prevent that heat from entering your garage.
  • Leave the garage door open:  Only leave the garage door open while you’re at home, otherwise you could be asking for trouble.  By letting the breeze pass through the open garage, the hot air will circulate out into the open.
  • Open the windows:  If your garage has windows and you haven’t yet purchased a window fan or AC unit, crack them open to allow a breeze to pass through.  Any circulation can help push out that trapped, hot air and make for a cooler garage.
  • Ceiling fan: Ceiling fans are another cheap alternative to cooling your garage.  You do need to be mindful when installing them (make sure the electricity is shut off as you install) and have at least basic knowledge of electrical work.  However, once installed, you can circulate the air in the garage all summer at little to no cost.

No matter the season, Danley’s is available to build custom size garages. If you are looking to add more space for your cars, then consider getting a two or three-car garage. You can choose from our popular styles such as gable garagehip roof garage, and reverse gable garage. Speak to a product specialist and get a free quote right now.

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