Hi, new to site. I am completing a 24X36 detached garage with office at rear of 144 SF. HVAC included. Want to insulate office walls on 2x4 stud construction with 9' ceilings but unsure if I should go ahead an insulate exterior walls. Garage faces north with 2-9' doors, exterior windows one east and west elevation and one window at rear facing south. Garage is uner a canopy of trees in spring, summer and fall. Built for Corvette storage and game room with private office. Any thoughts? ideas? how-tos?