Duck
Sarcastic remark goes here
So you put the mylar stuff directly on the insides of the vertical boards? Your garage walls have no interior surface?No the insulation. It's not regular fiberglass it's that mylar stuff with bubble wrap in the middle. I'm too lazy to finish that job.
I'm not stupid enough to use fiberglass where water can get in. The mylar acts as a wind breaker and water runs right down it.
I'd still get some 1x3's or 1x4s and some paint.
Or just say **** it and go watch bobtail the truck around.