Hi, Kman, there was a gap between the sheets of plywood, about 1/4" at the broadest point. The spot already had picked up mice nests, and as we found out, water got in there, and became trapped between the plywood and a layer of plastic that he put right under the plywood, over styrofoam insulation between the joists. This all led me to question the sanity of plywood on plastic, and we ripped out the plastic. If we put plastic anywhere down there, it will be under the joists, and I am not sure about that.

The crawl space will be heated in winter, vented in summer. Insulation between the joists is to moderate the difference in temperature between the crawl space and the room (maybe 40 in the crawl space and 70+ in the room, winter values).

The room (most of the house) has large gaps between cold and heated areas, like around every pipe and wire (none caulked or sealed from air infiltration). The floors stopped short of the walls by several inches, so the only thing between the room and the cold air was a bit of baseboard/trim. So, filling holes has become an obsession. Mice, cold air... stop the gaps.

Wedi found me a local dealer: $70 per sheet for 3' x 5' Wedi.

I took some photos of the tub and enclosure.

I need to go figure out how to upload the photos.

Thats a ridiculous price for 1/2" Wedi
It's about $36 here in Ontario.

Hate to hear what they are going to charge you for caulking, screws and washers.

Randall, I realize the price is ridiculous. I asked her to check whether she had written it wrong. They have not yet received their first palette. I think I am not going to use Wedi anyway.