I have a 13 year old 28x40x9.5' attached garage that I am thinking about updating mainly due to hosting a couple grad parties over the next four years. Currently is sheet rocked, taped and textured. Garage has floor drains, hot/cold spigot, and is kept at about 60° in the winter via LP furnace (vented). A concern I have is there are some mildew/mold stain visible on some of the rafters but mostly in the corners by the two walk-in doors. I feel like that issue has not gotten any worse since I installed two ceiling fans that run 24/7 a few years ago. I'm thinking about putting a coat of Kilz on and covering the walls and ceiling with that pole barn type steel sheeting for a fresh new look. Open to other options as well. If you've got some pictures of your own garage I'd love to see them.