How can I make my garage cooler in the Florida heat?
Thursday, October 7, 2021
Temperatures of over 100º F occur regularly in Florida garages every summer, and they are caused by three factors that all converge each hot afternoon. First, a garage is not a conditioned living space, so it is not required to have insulation in the walls or above the ceiling. So most homebuilders don't do it. Then there's the sun on the exterior walls of the garage radiating heat into it, and the heat trapped in the attic radiating downward. Add to that the lack of any installed ventilation system, sometimes not even a window, and you have the recipe for a hotbox. But there are several tactics you can use to cool it down.
Garage Screen Door - They come in sliding panels, motorized on an overhead track, and inexpensive lightweight removeable panels. Any style you choose provides plenty of passive ventilation to let the heat out.
Ceiling Exhaust Fan - The drywall ceiling of a garage is a fire barrier between the attached garage and the living area of your home. It is required by code to be continuous, without any openings. But we often see an attic access hatch cover in the garage with a screened opening cut into it, or propped open a little with a block of wood, to let the hot garage air vent into the attic and out the roof vents. This works, but it allows any fire that starts in the garage—which is statistically where many home fires start—to move quickly into the attic and race across the top of the the home.
One way to get garage ventilation without sacrificing fire safety is the GF-14 garage exhaust fan, manufactured by America’s Best Home Products (www.coolmygarage.com). The damper at the top of it, shown below, has a fusible link that automatically closes it when the temperature reaches about 200º F.
Air Conditioning - Because of that same fire safety issue, you cannot just add a supply duct or two in the garage from the house a/c system to cool the garage down. But you can install a mini-split heat pump system or window air conditioner that just serves just the garage.
Heat Pump Water Heater - How does free air conditioning sound? A heat pump water heater takes in hot air, transfers the heat to the the water heater tank, and then exhausts cool air back out. They are more expensive to buy than a regular electric water heater, but use less energy and, if installed in the garage, will make it noticeably cooler. See our article What is a heat pump water heater? for more details.
Insulation - Adding insulation helps buffer the garage from outside heat, and is definitely necessary if you plan to air condition your garage. A layer of insulation in the attic over the garage is easy to do, but it is likely that your garage walls have no insulation. Adding it there is more complicated, especially if you have concrete block exterior walls. And, of course, insulating the garage door is necessary to do it right.
• • • • • • • • • • • • • • • • • • • • • • • • • • •
Here’s links to some of our other blog posts about GARAGES AND CARPORTS:
• What are the common problems when a homeowner converts a garage to conditioned living space, such as a family room?
• What are the code requirements for fire separation between an attached garage and the house?
of Blog Posts
Top 5 results given instantly.
Click on magnifying glass
for all search results.
How To Look At A House
McGarry and Madsen's home inspection blog for buyers of
site-built, mobile/manfuactured and modular homes