I was thinking that. No finished ceiling, but low rafters where I have my "booth". I can do a tarp ceiling no problem. If it works in Minnesota cold, it will work here. Thanks for the tip.
I ask because, I had a large room 24' x 36' I couldn't heat, winter in Minnesota. Once I put thick plastic on ceiling as an air and vapor barrier, I had to turn pellet burner down from running wide open to low. Room was 100°+, by the time I had plastic up and taped seams on far end of shop. Some tape to seal up seams and stop air escaping can help a lot.