I guess a few details are required. I'm in central Utah, at 5,500 ft elevation. I own the house. It was built without a vapor barrier between the foundation and the blocks, much to my dismay. The north wall isn't just cold, it's damp. It was originally built to be a workshop on the family farm. The floor is suspended 2 ft above the ground and is just plywood. There is no attic. The ceiling is 10 ft high. We use a propane furnace right now, but will be installing a mini-split in a couple weeks.