Wait, maybe everyone should rip out their ductwork!! I really thought it was going to be a nightmare, but it is really just the oposite.
It's always fun when the HVAC guys show up at the house to clean the furnace and scratch their heads. Apparently, homes were sometimes done this way in the sixties. I guess they felt they could heat the basement for free.
Oh yeah, the darkroom is at an almost constant 68 degrees. In the really cold weeks we just had in PA, it dropped to 65. I'm never going to move!
John