29 above in my insulated garage and -26 outside of it. 55 degree difference. The steam rolled out like crazy when I opened the door.
I have an in-floor heating system but I never hooked it up. I really don’t think I need to. The heat from the vehicles engines seems to keep it warm enough. If I ever make it into a full time workshop, I’ll hook it up, but I don’t think it will take much to heat it.