Yes, well now they are anyway. Triple garage with a double door and two singles (on yard-facing single), when I first installed the heater only the double was insulated (albeit very thinly, I think it was R8) and the singles were just shitty quonset doors with no insulation, so I added some rigid foam to stem the heat bleed. For the second year I replaced the uninsulated doors with an R18 and an R12 which was a huge improvement, and last year I replaced the double with an R16.This quote is hidden because you are ignoring this member. Show Quote