Looking to cool down my garage this summer

[M-EGT]

And I need some help!
So, here's the pertinent information:

-block construction
-2 windows facing West, no bug screen or anything (that will soon change). Have some curtains to keep sun to a minimum while still providing light.
-uninsulated garage door that faces south
-apprx 430sq ft.
-located in Phoenix AZ, gets very hot!
-flat roof

My idea was to get a solar powered roof vent fan to vent directly into the garage.
But otherwise, I'm out of ideas!

 

[sublimate]

Use a low-E or reflective window film.
Insulate your door.

 

[steve308]

Window AC unit.

 

[Caman]

Move to Alaska

 

[WWIIjeep]

-uninsulated garage door that faces south

Definitely insulate your garage door. That single thing made a huge difference in my garage.

My idea was to get a solar powered roof vent fan to vent directly into the garage.

That's not going to help. The air venting out has to be replaced, so you'll still be bringing in 105-115 degree air by early afternoon.

Insulate your ceiling. If there's no attic under the flat roof, do blown-in insulation between the ceiling joists.

Then use a window A/C unit like steve308 said, and a couple of portable fans to move the air around.

Open doors and windows first thing in the morning to bring in some of that "nice" 80-90 degree morning air, then keep windows and doors closed as much as possible during the heat of the day.

 

[Jinks]

Mini-Split AC.

 

[bczygan]

Paint exterior bright white or reflective silver, including roof.

Power vent in attic.

Plant evergreen shrubbery all around to shade exterior walls.

Plant large trees close to building to shade roof.

Build lattice structures and pergolas to shade structure.

Install evergreen shrubbery area and draw cooler air from below shrubs to provide makeup air for exhausted hot attic air.

Install ground heat pump for AC.

Berm earth over structure for insulation.

Install earth covered roof.

Build 10' underground where temp is 55 degrees.

 

[east_tn_emc]

Would a portable swamp cooler do anything helpful?

 

[crab]

It seems like we're talking A/C here. There are free standing units on wheels, don't know how good they work. A big window unit would probably be the best option.

 

[1940_dodge]

Get one of those solar powered attic fans and put a couple up there. Also I agree with what the others are saying about planting around your garage to help shade the walls.

 

[JoeFin]

Don't waste your money with mechanical cooling until AFTER you thoroughly insulate your shop.

You probably don't have a dropped ceiling so you'll need to use Styrofoam panels in between the roof joist. Go thick - you don't want to cheap out here. Additionally IF you have a roll up door use 1" panels of Styrofoam there as well.

Now that you have a space that can be cooled - you have options

For many cost is a factor

Swamp Coolers are cheap to run but they introduce moisture and that means rust. Air conditioning - Spit system or window-box have operating cost associated with them - which would be 200% in an uninsulated garage

Now for the serious DIYer In-Direct Swamp with a Mechanical Assist will give you the absolute most bang for your buck with the fastest recovery should you happen to open the roll up door momentarily for one reason or another

 

[cabin fever]

My window unit in my garage does an "ok" job on the really hot days. If you turn it on BEFORE it gets hot, It will keep it about 10-15 degrees cooler then out side. If you turn it on after its hot in there, it will take FOREVER to cool it, best it does is removes the humidity, which helps a lot too, but not much cooler.

This summer I am planning to get a portable AC unit too, to use in my enclosed trailer, while at the races. When I am in the garage, it will be used to help the window unit. my garage is 24x36, and fully insulated and I'm in Iowa, so I would assume that a window unit in an un insulated garage in Arizona will not do a whole lot.

 

[CNGsaves]

Insulate, insulate, insulate !! With your flat roof, is there space to have gap so all that heat from cooking roof isn't radiating into garage (thus install drop ceiling)??

Also can't hurt to use fan in window at NIGHT to get garage as cool as possible.

If you can't do shade trees for west side (windows), then install awnings.

 

[Kevin54]

Insulate, insulate, insulate !! With your flat roof, is there space to have gap so all that heat from cooking roof isn't radiating into garage (thus install drop ceiling)??

Also can't hurt to use fan in window at NIGHT to get garage as cool as possible.

If you can't do shade trees for west side (windows), then install awnings.

THIS^^^^. Nothing will keep it cool easier than insulation. Walls and ceiling. Can you see your roof from below from anywhere? And what sort of material do you have on the outside of the roof? Is it light or dark in color?

You can add furring strips inside, or build 2x4 walls inside, and if using furring strips, use Styrofoam. If you use 2x4's either Styrofoam or fiberglass batts. Do you have a ceiling between your roof and the interior of the garage? If not, you want an insulated ceiling.

Once insulated, a small window air conditioner, or even a fan should keep working conditions comfortable.

 

[Falcon67]

It seems like we're talking A/C here. There are free standing units on wheels, don't know how good they work. A big window unit would probably be the best option.

The free standing units - in my experience - are not worth the wheels they roll on.

 

[PFSard]

- What type of block? Slump block?
- I'm guessing your walls are already covered with shelving, cabinets, etc. on the inside.

I'd spend money on passive efforts first :

- Install 90% sun screen fabric on windows.
- Insulate south-facing garage door. And weatherstrip.
- Vegetation and/or lattice to shade walls outdoors.
- Insulate ceiling (and walls if possible).

I'm guessing you have lived there at least a season. Hopefully, you have taken before modification(s) base line temperatures. After you do the passive installations, compare temperatures.

I've lived in my house for four years (attached garage 400 sq ft more or less). First summer, the temps in mid-to-late afternoon would hit 105. Insulated (styrofoam) and weatherstripped door. Had insulation blown in the ceiling (Had 4" Added 8" more). Temps in mid-summer stay under 95.

I have an AdobeAir SC3500 portable evaporative cooler in my garage. This is not going to help you in the July through September period. I don't work much in my garage in the summer. I have a 42" MaxxAir fan like the one in the link below. If I were to work there in the summer, I would probably have to install some type of AC unit.

I'll probably install an exhaust fan eventually to try and cool the garage down more at night. But, as you already know, it's tough since the outside night temps in summer hover around 85-90.

http://www.amazon.com/dp/B005JQJHR2/?tag=atomicindus08-20

I'm interested in hearing whatever other options you may encounter. And your final results.

 

[M-EGT]

Thanks for the suggestions!
There is alreadya drop ceiling in there. Likely uninsulated.
Will look into garage door insulation and window tint. Also vegetation outside. Not sure if we can afford ceiling insulation right now.
The top of the roof is the white foam.

 

[TangoFoxTrot]

As someone who lives in dry AZ, I actually think swamp coolers make a lot of sense for garages. Most parts of the country thy don't work well but in the Southwest they do.

My FIL has a dedicated wood shop that he put a "through-wall" swamp cooler and it's really impressive the cooling capacity. I definitely think it makes a workspace comfortable enough to be in the summertime. It's not going to be AC cold, but a nice cool breeze. It also cools it down quick.

Obviously, if money is no object, get the place insulated and put something like a mini split, but you're looking at an expensive project. Also, AC units just don't do well in situations where you're going from like 100 degrees to 75 degrees, which is how I see it being used. It's hard on the unit itself and it takes a while to cool down.

A swamp cooler uses about the same amount of electricity as a few lightbulbs and some water, it's pennies a day and the unit itself is pretty inexpensive
Here's a similar kind he had

 

[Hot Rod Home]

Why not use the solar powered roof vent to exhaust the heat build up inside the garage and put a box fan in window to bring in some cooler air from a shaded side of the garage?

 

[Wizzard]

Window unit or a mini-split. My parents have a Sanyo mini-split and it works awesome, just size it correctly.

 

[Ss95003]

Build 10' underground where temp is 55 degrees.

by far the best and clearly easist solution.

 

[PFSard]

Build 10' underground where temp is 55 degrees.

by far the best and clearly easist solution.

This area of AZ does not have many basements. I'm guessing that, given that most of the year the soil is hard (like concrete), going down 10 feet would be an expensive proposition. I wonder if anyone has gotten quotes to build 10' underground.

 

[Kev442]

Now, this is a sure sign of spring. With apologies to the OP, your post is the first of a wave of " I want to cool my garage, but can't afford/don't want to insulate the roof/attic". There will be many, many more...

 

[drmarkr]

With no insulation, you have no real choice besides evap cooling....and even that's going to be taxed. But get yourself either a window unit cooler, or consider cutting a roof jack in and putting one up top. Can you build a framework to the west of the garage and put up some sunshade material to reduce afternoon direct sun exposure? Try it....that will help as well.

Frame it out and insulate it, covering wtih dry wall or OSB?

Large air moving fans as well.

I'm in Tucson and my shop does very well with evap....but it's also insulated well. And, of course, monsoon is going to be sticky with evap.

 

[bczygan]

by far the best and clearly easist solution.

Actually in middle eastern countries they do something with this. They build a chimney into the house structure. Natural convection exhausts hotter air out the top of the house and pulls cooler air up from the basement or lower levels and the earth itself. An iteration of this is to install a bunch of pipes under the earth and use the cooler air in them as a source of lower temperature air. This can be active like a heat pump, or passive.

The house also has a lot of masonry mass which works with the day night cycle to soak up heat in the hot daytime, and radiate it into the living spaces during the cooler nights. Adobe in our SW does the same thing.

 

[Ss95003]

This area of AZ does not have many basements. I'm guessing that, given that most of the year the soil is hard (like concrete), going down 10 feet would be an expensive proposition. I wonder if anyone has gotten quotes to build 10' underground.

I forgot to use the sarcasm text.

 

[shannonw]

For me in FL an insulated garage door made a big difference (block construction). We finally did ours with the upgraded one (it’s thicker i don’t recall but it’s thick ..2 inches or so. It still gets hot in the very middle of summer but it’s a good 10-15 deg cooler, and if it’s hot to me i open the door to the house and about 30 minutes later it’s fine. My kids play out there now during the really hot summer days when before no one would go out there...it would be swealtering...just miserable.

insulate well above the garage too. I’d still like to add a mini split but i’m in no rush as this works pretty well so far but i’m sure a mini split would be more efficient than letting some hot air flow into the house.

 

[J Persons]

On my gable roof, I used Attic Foil and no other insulation. It has dropped the temp considerably in the garage. I think it can be used with a flat roof, just be sure the edges are open to vent out the hot air.

 

[LS6 Tommy]

Paint exterior bright white or reflective silver, including roof.

Power vent in attic.

Plant evergreen shrubbery all around to shade exterior walls.

Plant large trees close to building to shade roof.

Build lattice structures and pergolas to shade structure.

Install evergreen shrubbery area and draw cooler air from below shrubs to provide makeup air for exhausted hot attic air.

Install ground heat pump for AC.

Berm earth over structure for insulation.

Install earth covered roof.

Build 10' underground where temp is 55 degrees.

A good idea if you have Jay Leno's budget

Tommy

 

[M-EGT]

Build 10' underground where temp is 55 degrees.

by far the best and clearly easist solution.

While I'm at it I'll just expand to a 3 car garage

For me in FL an insulated garage door made a big difference (block construction). We finally did ours with the upgraded one (it’s thicker i don’t recall but it’s thick ..2 inches or so. It still gets hot in the very middle of summer but it’s a good 10-15 deg cooler,

Thanks. this will be my first project then, since you and a few others say that insulating the door will be a big gain (with little involved). I'll look into insulating above the garage too.

thanks guys