garage-doorinsulation
I'm in South Florida and I have a west exposed garage door. The garage door is metal (possibly aluminum). The garage is not air conditioned. There is insulation between the house and the garage. There is no insulation in the garage walls, which are concrete blocks covered with stucco.
Would there be any benefit to adding insulation to my existing garage door?
I just finished our garage this past summer and here are a few things I did.
I insulated the garage door by cutting pieces of rigid insulation foam to fit into each piece of the garage door. You can glue them on and then seal the edges with expanding foam or caulk.
On the side of garage door I installed weather strips and also on the top/bottom of the door so that it is sealed when the door closes.
If you have any windows I would make sure to seal them (I boxed mine in with wood and then caulked). Also depending how you finished the bottom of the garage walls, I would seal the bottom (my drywall buts up right to the cement floor, so I sealed the space with expanding foam and cut the excess away).
I would not waste the insulation on an outside wall unless your garage door was getting insulation. Drywalling has benefits though... First you need to use fire resistant (5/8) in most places in the US for garages, a fully drywalled and painted garage will be deemed nicer by those wanting to give you money for your house, white flat walls reflect light the best, noise reduction... all I could think of.
Small tip if you do this... Run some crosses at like 5 and 7 feet along the wall. That way you have places to nail things without measuring for a stud.
Best Answer
In my experience insulated garage doors are terrible in the summer. While they do a fantastic job keeping the heat in during cold winter months, the lack of ductwork for actively cooling the space makes it into somewhat of a heat-trap with temperatures regularly hitting 120F when its only 90F outside.
This all changes though if you have AC running into the garage, in which case I imagine they'd be great.