I have a slightly larger outbuilding that doesn't have a floor. The outbuilding is built on raised concrete blocks, so the floor is just the ground. Now I'm planning to build a proper floor, but I'm a bit unsure how to do it fully. First, I thought about laying plastic on the ground as a moisture barrier, then tape all the seams to make it tight to prevent any ground moisture from coming up. Then I'll frame the floor, and they will sit in beam hangers attached to the concrete blocks. The distance will be about 200-300mm from the underside of the joists to the ground. Then I'll put subfloor boards at the bottom of the sections between the joists, and then insulation, and then I'll put chipboard on top as the floor. But is a vapor barrier needed between the insulation and the chipboard?
