Mini crawl space
I have decided to convert a piece of my timber frame barn into living space on my new home.( the barn is there) what I would like to do is elevate a 2x 8 floor above the existing slab. This would hanger onto the existing perimeter grade beam that sits on top of the concrete stem walls. I would set the floor 1.5″ higher than the grade beam to create a thermal break with a narrow ripping of eps. So I would end up with about 10 inches beneath the floor assembly. So I am considering the following options, panelizing the floor and preinstalling sheathing or perhaps some kind off wrap underneath( prior to installing) This would allow me to dense pack the floor from the top creating a unconditioned crawl space above grade if you will. I would block off the opening from the balance of the barn/ garage using a combination of rigid foam and p.t. Lumber. I could install vents here if needed.
Another option would be the same frame assembly with a couple layers of foam directly on the slab and leaving the floor assembly conditioned if you will. Transitioning the foam vertically would require spray foam to make the rim assembly adequately insulated. Another option would be to build up the layers of foam high enough to pour a slab . Say about 6 or 8 inches of foam then 4 inches of concrete, then I would need to insulate the grade beam creating some sort of insulated base trim. This brings me to how to insulate the timber frame. But I will save that for another post…. thanks all in advance.
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