Hi, I have a cabin on piers, with insulated floor. The joist bays are filled with fiberglass bats, bottom side is covered with 1/2 chipboard, sealed and battons at the seams. Vapor barrier on the top / warm side, and 3/4″ t&g plywood over that. So far it’s been warm and dry and critter proof. I’m in Canada, winter temps in the -5 to -25 deg C are not uncommmon.

I’ve opened it up in a couple of sections on top (after @ 20 years in service) this year to run some subpanel wiring and drain lines etc in the joist bays, as part of a remodel I’m doing – and the structure looks like the day I put it in – nice and clean and dry, at least where I can see. It’s been a “camp” so there hasn’t been any flooring installed over the ply, just left it as is until now.

Here’s my concern – I’ve been reading some threads here and I notice that some of the experts are leery of putting vinyl flooring down on top of an insulated floor in some circumstances, as the vinyl is impermeable. I have a supply of Armstrong click vinyl that I got a good deal on, like the way it looks and easy to lay down. I plan to install soon and I’m thinking that this will be no different than the vapour barrier that’s already there in my case from a “breathable” perspective. I’m assuming the floor breathes out the bottom chipboard to some extent and this won’t change.

这将是伟大的,如果你人在这里啊ffer up your thoughts on this. It seems I must have done something right back then, as it’s still solid and dry, but I don’t want to screw that up now.

So any sanity checks are much appreciated.