Yes, I'm actually considering placing all three outside on the wall along the back of the garage. Couple things though, neighbor on that side works nights so we would have an issue with noise if it isn't insulated enough, and weather/ventilation considerations. I'd want it enclosed for the weather and sound proofing, but open enough to have good ventilation.

 

I have heard lots of horror storys about putting air compressors in the attics of garages. Even with doing extra bracing and such that after awhile the vibration caused weakness and boom ya have your compressor on the floor. I would opt for an "out house" or "dog house" . Alot easier for draining, maintanance, etc.
Just my 2 cents.

 

I have my compressor and extra tank bolted to a pallet, then put on the top of my pallet rack, with a 1" diameter hydraulic hose connecting the compressor to the black pipe air system (man did that take some time to set up and get leak free)


I would HIGHLY recomend an auto drain valve. That is the easiest and most effective way to keep air out of your system. I've seen several different designs for sale on ebay. I got an electronic IR version, which has worked great for a couple years now, but has special fittings not pipe, so it's a bit difficult to work with if a fitting is damaged (like mine.... which leaks just a touch)

It really depends on how much air you will use, the dimensions of your shop, etc.
Putting a compressor outside in a "shed" is a great idea, as long as you remember to keep it mantained, and prevent any freezing problems in winter... it will make your shop quieter for sure

 

man im glad that i've got a indstural qunice(sp?) comming with two 200gal air tanks. with the 400gal @ 400psi i'll never run out of air. I got the compresser and tanks out of a tug boat thats being scrapped. The Main engine takes 350psi to roll over @75rpm to start it. gonna have the compresser inside the grage and the tanks will be out side on the back of the grage.

 

Grainger sells rubber isolation mounts in different sizes and bolt/stud combinations. I'd put them outside under a leanto shed. better for maintainence

 

After reading more post I want to say I did this with my compressor and lines the lean to with 2" foam insulation for sound and installed an exhaust fan for vetilation. I have the system wired thru a contactor with a remote enable switch inside. actuate the switch and compressor runs. it is controlled by the local pressure switch. I also installed a normaly closed solinoid valve and a time dely off relay in the drain. Every time the compressor starts time tank is drained for 3 seconds.
FYI