Thanks for your question! I'm a noob and since my garage is detached, I wouldn't have even thought of it. I did blow insulation in my home's attic a few years back and remember getting the same advice them. I guess a structure is a structure, whether home or just garage!
I like the way you're thinking! Unfortunately, I don't have the resources to do something like this, myself. I'm interested if you actually do this, how it turns out!
My garage is a detached concrete block structure that is recessed into a hill on three sides. It's also intended as a tornado shelter, so it's VERY sturdy. It has an attic area that has a floor for extra storage.
My home is in the greater Atlanta, GA area. Humidity is a huge problem here, both...