We own a log home in northern NY. Cabin sits on top of a dirt crawlspace (unheated but has electric hot water heater and plumbing). We would like to heat it so heat would rise to 1st floor and make it warmer. (We have Monitor heater in living area) Heat is adequate but not really warm.

In crawl space we have completely encapsulated it: We had closed cell foam sprayed from ground to rafters and sealed all dirt with 10mil plastic so no moisture problem at all and all 4 vents to outside were foamed over.

I would like to put something like a direct vent Rinnai propane space heater (obviously away from foam walls and plastic) We have probably 3' and in some places 4' of height to bottom of floor rafters.

We do not have insulation in crawl space ceiling (floor rafters) since we need heat down there so no pipes will freeze.

Questions: Can it be done and would I also need to put vents in to open airway from crawl space to 1st floor? I read that air pressure would have to be equalized.