its a double car garage, windows across the top. When we had it installed we didnt opt for the extra money to get an insulated one and boy are we sorry. Our previous garage door was wood, which never got hot to the touch so we had no idea how hot a metal one would get - the heat that thing radiates is incredible and its not even in direct sun
Yes, it's possible. Look on lines for tutorials since there are many options and techniques for doing it. Check out the options and go for the one that seems to work best for you.
You could get foam insulation and glue it to the door on inside. I got the insulated and wow it saves in heating whatever it cost. You have to take that into account when pricing stuff, is there a payback somewhere. Next time you'll know, unfortunate but it is a lesson learned and I'm not being cheeky, I've learned more than one the same way you have.
I just bought 2 Styrofoam insulation, cut it to size with an electric carving knife and glued it directly onto the door panels with Liquid Nails. You do have to allow a little tolerance where the joints bend as the door goes up. I put the panels on first, then carved off a 45 degree slice off every panel at each joint. BTW, painting the door bright white on the outside will make an amazing difference as well.
