[retiredguy123]

Originally Posted by GpaVader

I have done this in my 2 car w/golf car garage, 3.5 years ago. I had a mini-split installed. As Villagethinker suggested, I did insulate the garage door, as I have an East facing door, that made a huge difference. I also had the garage door windows tinted. I elected not insulate the ceiling because it was already set up for storage and I was not sure I would gain as much since heat rises and want to let that out. I shopped around on the mini-split and opted to go with Munns, the did my houses HVAC and they had the best value.

I did this because my garage is also a workshop for both my model building, where I have a small spray booth and also for my 10 needle embroidery machine and 3D printing. Adding this added about $15-20/month to my electric bill in the summer months. I typically have the space set for 74* and it recovers nicely when the door is opened for a long period of time. My main purpose for this is reducing humidity in addition to making it more comfortable.

I would suggest that you reconsider not insulating the ceiling. You are losing a lot of energy through the roof.