I am actually looking at a supplemental solar heater for this space, wanting to warm it during the day and hoping the concrete floor and other objects will act like a heat sink and keep it a little warmer at night.
Thanks guys, some great points and information. The space and garage door will be insulated, but it is still going to be pretty cool most of the time.
I had not considered rock wool, but that sounds like a decent alternative.
New member from Colorado ski country. Considering raising an 850 ft2 house and putting a 2 car garage under part of it with the remainder a work area/office. Any thoughts about how to insulate the floor and furnace runs as the garage will be minimally heated? I am considering a fiberglass...