Hello everyone. I have a new construction home in Phoenix and have been in it for a year now. Obviously, it gets hot in the attic and and in the garage directly below.

Here is what I have. Our two car garage has a metal door that faces west. So it gets hammered by sun all afternoon. We have windows on the top panel and I've put window tinting on it, not really for sun protection but to cut down on anyone being able to look in the garage. The door is not insulated, but I may do that this winter with the foam insulation pieces to try and cut down on the heat in the garage.

The garage also has two soffit-style vents, one near the floor and one near the ceiling on the northern wall. It's there to allow for air flow in the garage, but really does nothing. I've put a small plug in fan in the vent to help move some air, but it's really not doing much at all. It's still approximately 115 degrees in the garage every evening and near 110 in the morning.

The garage has soffits, but they are different from what I'm use to seeing. I'm familiar with a soffit being an air vent type cover, but instead, these are round holes that kind of look like something in a bird house. They go all around the edges of the attic over the garage. I also have cement roofing and vents in the roofing as well.

I was thinking of adding a bath room type fan or a larger fan to the ceiling to draw the heat up into the attic and using the fan, to push it out of the attic. By putting pressure into the attic from the fan, I expect the air will be expelled out of the soffits. Or, I could take ductwork from the bathroom fan and run it to a soffit hole and vent it that way.

I'm not sure if there is a better way to do this. I'm not looking to spend $$$$ on this, but if I could drop the temp in the garage, the laundry room would not be so warm, the garage refrigerator could run less and it would just be a lot more pleasant when you are loading the kids up in the car.

Is this the way to go or are there any other suggestions on what to do to help cool the garage/attic?

Thanks,
John

 

How about a full size exhaust fan or fans in the garage and/or attic?

 

How about stoping the heat from getting into the garage by using spray foam on the walls and atick and the sheets on the door.

 

About exhausting air out of the garage. Do you have any gas appliances in there? Be cafeful not to cause backdrafting. Also, there may be code issues with any type of vent opening between the garage and the attic, not sure.

The foam on the garage door could be the best change you can make. When it gets hot from the sun, you basically have a 16' x 7' heating element at prob 130-140 degrees or more, and thats if it's a light color. BTW, if you just buy sheets of foam and cut them yourself, it will prob be a lot cheaper than the kits. You may be able to get it thicker than the kits have for less money. An electric carving knife from a thrift store for $5-10 cuts right thru them.

More insulation in the attic above the garage, and increased attic venting for the whole house, would be my next step.

Make sure those little holes for airflow aren't blocked by insulation in the attic. At least you have some soffit venting. My house here in Kingman has the exposed rafters and blocking between them on the top plate, so all I have is 2 gable vents and 2 useless (due to placement) turbines up near the roof ridge. Attic temps around 150-160 near the peak on hot days.