I used to think a 6 mil vapor barrier was fine for basements, but a job in Seattle proved me wrong.

2 comments

2 Comments

Wait, you were using a 6 mil in Seattle? That's asking for trouble. The ground is basically a sponge up there all winter. I saw a basement with a 6 mil barrier that looked like a waterbed after one wet season. It just can't handle the hydrostatic pressure, it gets tiny pinholes you can't even see. You really need that heavier stuff, like 10 or 15 mil, for any real damp soil. Anything less is just a temporary fix.

briannguyen17h ago

Maybe it's just me but @shane_anderson, is a 6 mil really that bad? I've seen it hold up okay in some spots.