Heard a guy at the supply house say he never uses a vapor barrier on interior slabs

I was picking up some fiber mesh in Tacoma yesterday and overheard a conversation that got me worried. This older finisher was telling a younger guy that putting down plastic under an interior garage slab was a waste of money and time. He said, 'It's inside, it'll dry fine, I've skipped it for twenty years.' That really stuck with me because I saw a job fail just last fall from exactly that. A homeowner called me to look at their new garage floor that was already dusting and had a huge crack after six months. When I asked, they said the previous crew didn't use any poly. The moisture came up from the ground unevenly and ruined the cure. It's not worth the risk to save maybe $150 and an hour of work. Has anyone else had to fix a slab where someone skipped the vapor barrier?

2 comments

2 Comments

oliver81122d agoMost Upvoted

Man, that's the exact kind of shortcut that drives me nuts. It reminds me of people who skip priming drywall because the paint says "paint and primer in one." Sure, it might look okay for a year, but then you get that weird peeling and have to redo the whole wall. They're saving an hour of work to create a problem that takes days to fix later. That vapor barrier is cheap insurance.

caseyg6522d ago

Totally agree about the paint and primer thing, that's a perfect example. I watched my neighbor skip the vapor barrier under his laminate floor last summer to save a weekend. Now his boards are buckling and he's gotta tear out the whole room. It's crazy how people chase a tiny time save and end up with a huge mess.