Any cheap / free ideas to cool a garage?

[clinebarger]

I tried this one. Supposed to cool 4x the size of the garage and it won't do anything. I put it in our bedroom window and it's still not a good cooler at all

You have to put it directly on you like I already stated & it needs to be larger (More CFM), Your location is dryer than mine & should work better for you.

I'm just far enough away from the Gulf & just far enough West for evaporative coolers to work on hot days after the morning humidity burns off.

I don't think A/C will work without insulating the walls!!

 

[PandaBear]

So, no neighbor near you right?

Can you buy some patio umbrella and put them all around your exterior? If not, can you put up a bunch of aluminum foil or metal "fence" around? I think most of the heat you get is from the sun light and if you block off the sun hitting your house it would significantly cool it down.

Or follow the Greeks and paint your house white and baby blue.

 

[4WD]

So, no neighbor near you right?

Can you buy some patio umbrella and put them all around your exterior? If not, can you put up a bunch of aluminum foil or metal "fence" around? I think most of the heat you get is from the sun light and if you block off the sun hitting your house it would significantly cool it down.

Or follow the Greeks and paint your house white and baby blue.

If there is just one side taking intense sun - astrofoil is easy to put up. It’s a good radiant barrier - plus a bit of insulation …

 

[JimPghPA]

Instal a heat-pump water-heater in that garage and you get hot water and a cooled off garage.

 

[ArrestMeRedZ]

FWIW I've lived on George AFB around the corner from you and in Apple Valley and the weather was the same. At George the base housing only had a roof mounted swamp cooler. It worked just fine except for the few monsoon days out of the year when the humidity was way up.
A properly set up and sized swamp cooler with a downdraft from the roof and an exit vent should provide the solution.

 

[ecotourist]

A doctor I used to work with said that 30 years ago in India they sprinkled water on their roofs so the evaporation would cool their buildings. There is a good theoretical basis for that, so it wouldn't hurt to try it. You could start by manually spraying water from the ground or from a ladder. If it helps you could set up a micro-drip system along the ridge line (like people use in gardening) to minimize water usage.

I expect that you have an insulated ceiling in your garage. In near desert heat, that attic space must get fantastically hot. Simply ventilating that space would help quite a bit.

As the next step after those two, I think you will need to insulate the walls, which isn't free but still pretty cheap. In Edmonton I insulated the stud spaces using R12 insulation with a 6 mil poly cover, in that case insulation against the cold. It would have been more elegant to drywall over it but functionally it worked fine.

And white paint would help too.

 

[Snagglefoot]

For the OP, how is the interior finished? Are the studs visible? I am guessing you get a massive solar load on the south wall late in the afternoon.

If you have studs visible, you can pull back all your equipment away from the wall, rent a do it yourself foam spraying system, and spray purple closed cell foam between the studs. It’s R7 per inch so even 2x4 studs have room for R24. Then, put up drywall or plywood. To cheapen things up you don’t have to finish the drywall. Doing just the south wall would make a difference.

Edit. I just saw the south side only has 3 ft exposed. Get those 3 ft insulated with closed cell spray foam. Better than nothing.

 

[dlundblad]

Have a heat gain calculation done and get a mini split sized accordingly

I’ve often wondered when it comes to sizing a mini split, is the ceiling height taken into consideration?

800 square feet with say a 9’ ceiling is different than 800 square feet with a cathedral ceiling.

 

[burbguy82]

My garage is 20ftx24ft. We put insulation on the roof when we reroofed it. No insulation in the walls.

It gets unbearably hot in there during the summer. A few years ago I put an evaporative cooler in a window which only pushed the cool air out the whirly bird on the roof without effecting the inside temp.

Anyone have any ideas I may not be aware of? Adding insulation to the walls would be a serious job and not something I'd want to do in the summer.

I have a similar situation. Fans are the only thing that I have found to make the space tolerable. I have an exhaust fan in the rear wall, and when hot, I roll a big fan in the roll up door and let it rip.

Air movement is the only answer I see.