IS GARAGE ATTIC RADIANT BARRIER WORTH IT?
Our home garage gets tons of sun, which makes the temperature unbearable.
PARTS LIST
On a hot summer day, we’ve tracked temperatures upwards of 90 degrees in our detached two-and-a-half-car unfinished garage.
We have no insulation, just two-by-four walls and siding. The garage also has a small attic space for storage, but parts of the garage ceiling are opened to the attic. This really brings the heat in and the temperate gets as high as 100 degrees during a sunny summer day.
We needed a way to minimize the heat pouring in from the attic, so we started looking for possible solutions to help reduce the heat. While searching we ran into a product called Reflectix which is a brand of radiant barrier. The product is made to help reflect or reduce radiant heat coming through the roof.
So we decided to purchase and install a few 48-inch wide rolls for the garage attic.
PRO TIP: Don’t try to install a radiant barrier in your garage attic when it is 90+ degrees outside :)
Installation is easy, but make sure you work during a cool period. Start first thing in the morning or wait a few hours after the sun goes down. That’s unless you want to lose about 5 pounds of water weight.
While installing the radiant barrier make sure you keep a gap between your plywood and Reflectix. We did this by stapling the radiant barrier across the rafters and leaving an open space from the bottom soffit vents to the top of the roofing ridge vent.
Reflectix Radiant barrier installed in garage attic
The gap allows air to continue flowing from the bottom to the top of the roof.
As we continued stapling the Reflectix to the garage rafters, we could instantly feel the difference.
The ridge and soffit vents need to stay unblocked. This allows the hot air to properly travel from the bottom to the top of the roof which also prevents moisture buildup inside the attic. After fully covering the rafters in the garage attic space, we retested temps from the top and bottom of the garage.
To our surprise, we saw about a 15-degree drop in temperature. Now the garage doesn’t get super hot as quickly as it did before. But the rest of the garage is not insulated, so we decided to add insulation along with some additive cooling assistance. You can read more about fully insulating and cooling your garage here.
