Responses (3)

Murray Kipp
Murray Kipp 2 years ago
Mike Reynolds 2 years ago

Hi Murray, 

I think you have a pretty good idea of what matters here, so I would say yes, only keep the areas warm that you need to keep warm, where plumbing and any other mechanical components are. If you have insulation in the joists already that’s probably not a bad thing, that would enable you to keep it just warm enough down there to keep it operational, but not feel to much cold on your feet.

Most important is a vapour barrier on the dirt floor to keep moisture down. Next best if possible is insulating the floor as you will lose heat to the ground. Sounds like you are exploring that idea, so if its flat enough to lay some rigid foam sheets down on top of the poly that's great. Great if you can still walk on it carefully and not crack it due to uneven ground.

As long as the space is kept dry ( poly on the dirt and a dehumidifier) then the insulation in the joists will help save energy if the two spaces are different temperatures, not enough so that I would make a grand investment in material and labour to separate the spaces if they aren’t already, but it shouldn’t be a problem to leave it in place.