As mentioned, the wife and I are buying a new house. Cuss swear, cuss swear. We have finally sold ours, and found the new house. The new house is only 1.5 years old. My shop will be in the double deep third car garage portion of the house. During the process of looking at the house, I knocked on the walls of the house between garage and house, and then did the same to the garage to outer wall areas. It has nicely insulated doors, and as far as I can tell, they are quite tight in the frame. I am sure from the sound of the "knocks" that the outer walls of the garage are not insulated under the drywall, but the inner walls are. Also, the garage ceiling is not insulated. I plan to send my pipe cleaner skinny nephew up to put fiberglass batts in the attic, but I am unsure what, if anything to do about the walls. Do you think they should be insulated? Heat rises, but some will be lost through the walls also. If so, what is the best, most cost effective way to insulate previously finished walls. By finished I mean that they have been drywalled and have first tape coat. If it is necessary to insulate them, I can take down the drywall and put kraft face in, but would rather not go to that length if it is un-necessary. Blow in is also an option, and I am sure there are some others. New house, so money is definitely an issue.
Some facts that might influence your advice. I live in Idaho in the high mountain desert. The winter temps average near 0*, and -20* is not unusual. At times it can even get to -40*, but not common. The wind blows here; a lot. Often 30-40 mph in winter from the south, and the shop is on the south side of the house. Summer runs between 85*- 100*, and the wind blows some. We don't get much snow (natures insulation). I know, seriously, why would anybody live here? But I do.
I also am looking for heating ideas. The house has gas, but it will be difficult getting it to the garage. I can do electric easier. My current shop is heated by a 3 burner heater on top of a propane tank. I would really like to get away from that.
If any of you have ideas, I am all ears. Thanks in advance for your time.