To insulate or not to insulate? (unconditioned attached garage)

We are doing a reno on a 2001 home in N. GA (CZ 3A/4A).
I’m seeing a lot of conflicting info online about whether or not we should air seal and insulate the exterior walls of our unconditioned attached garage. There is not a living space directly above it, but there is attic space that is shared by the rest of the home. We already plan to air seal and insulate the garage ceiling and the wall that is shared by a living space (this wall also has our water heater closet in it). Is insulating all of an attached unconditioned garage a good idea in my climate zone?
Our existing garage door is nowhere near air tight, so is air sealing all of the walls and insulating just futile anyway? I also worry about trapping hot humid air in there during our sometimes brutal summers.
Thanks in advance for your input!
Tiffany
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Replies
From a dollars and cents point of view never is the answer.
Zero dollars are saved.
From a green point of view never is the answer.
Materials are wasted that should be saving energy in another building.
My wife insisted on the luxury of an insulated and drywalled garage.
What I have found is the garage is almost always hotter than the outdoors. Ok maybe it is cooler than the outdoors for 2 hours a day in the peak of summer. In the winter it is nice that things almost never freeze and the car is always relatively warm. When I put out the trash before bed in the summer the garage feels like an oven and it is much cooler outside.
Walta
If we don't insulate the exterior walls, can we still drywall them? Or use purple drywall maybe? Or should we leave them unfinished (exposed exterior OSB, studs, etc.)?
The wall shared with the house probably requires drywall as a fire barrier. But the other walls likely do not require any finishing. It would be more constructive if you keep the discussion inside of one question instead of making more than one about the same topic.
Sorry for the multiple posts. For some reason GBA removes my ability to add any comments to a post after a certain point. Thus me adding f/u questions as a separate post.
The people that designed and bought the software that this site runs on were very special people.
They put a reply link after every message. If you click on that link for message number 2 and there are 30 other posts in the thread your post #33 will appear just under post #2 making it almost impossible to find mercifully the software only let this happen about 3 times.
If you ignore the reply link and type in the reply box at the bottom your post goes to the bottom like one would expect and a seemingly unlimited number of reply box entry are allowed.
Walta
Thanks so much for helping me with that!