Garage cooling/ venting

[luckyblue]

Hello,
I am wondering if someone could recommend the best method to cool my very hot garage. I am in a desert-like area of southern California, and in the summertime my garage can heat up to 120 degrees. I have a 20 x 20 open beam/ open attic barn style garage, with no insulation. The garage has no eaves. I have done a little research and find many people say Not to use a powered fan unit, but I think they are mostly talking about house attics as opposed to a garage. Should I consider an electrical fan in the roof or gable end, or go with a whirly type radiant roof vent? Do I have enough intake air for a motorized fan, or would I need to add a larger intake air vent since the only existing vents are 2- small 6" x10" vents near the floor.
Any help would be greatly appreciated. Thank you in advance!

 

[vartz04]

Add insulation

 

[pseudorealityx]

Insulation is your friend. Just adding a fan is going to push around 120 degree air... it'll still be hot.

After that, an evaporative cooler might make sense since you're in a very low humidity area.

 

[pattenp]

I suggest the swamp/evap cooler also if you have the dry climate for it to work well.

Edit: Evap coolers use a lot of water, 3-10 gal p/hr depending on size and how low the humidity is.

 

[kenfath]

I have a ~625 sq/ft attached garage. Stucco outside walls face south and west and get full sun. First thing was to insulate sidewalls using R13 foil faced bats. In July, August, Sept it would be almost as hot as the out side, about 105F, insulation helped some. Next, added a power vent roof vent and although it took me another five years to wire the vent the opening allowed the heat to escape. Next addition was a 18,000 BTU window A/C installed thru the wall. Only ran it while I was working in garage but it made the room comfortable. Eventually finished the space with R19 in the rafters and ceiling joists, R15 in the walls (replaced earlier insulation). Added a ceiling fan in the workbench area. Also provided two vents thru the ceiling which can be closed off. They provide air for the vent fan which keeps the storage area above garage at a manageable temp. A/C got the space down to 72F while 105F outside, and it was cycling (not running continually). Have since readjusted it to 78F and it is very comfortable. These improvements were made over a thirty year period.

My recommendations are: insulate; provide vent in roof; consider a 15000 BTU window A/C, good sales taking place now; finish walls and ceiling; consider a ceiling fan. Oh, don't take 30 years to make it all happen!

 

[luckyblue]

Thanks to everyone for your advise. That really helps a lot!

 

[Nutcase]

I put an electric exhaust fan in the attic on a thermostat and a 2 ton window unit in my 3 car detached garage. It can be 100 outside and it will freeze you out in the garage.