Spent 4 hours fighting a subfloor leveling issue that should have taken 30 minutes

On a remodeling job in Phoenix last month, I tried using self-leveling concrete on a plywood subfloor without priming it first. The stuff just pooled in low spots and took forever to feather out because it was absorbing into the wood. Has anyone else had a DIY leveling job turn into a full day adventure because of one dumb mistake?

2 comments

2 Comments

burns.brooke16h ago

@kai_stone99 nailed it with that moisture absorption thing. Read a forum post a while back where a guy tested it side by side - primed vs unprimed on plywood. The unprimed stuff cracked and took forever to set because the wood basically stole the water it needed. Primed plywood let it flow like it should and cured in like 20 minutes. You probably saved yourself a headache in the long run though because if that stuff dried weird under your flooring it would have caused squeaks or tile cracks later. Live and learn on that primer step.

kai_stone9919h ago

That self leveler on plywood mistake is actually pretty common. The moisture from the self leveler gets pulled into the wood too fast which messes with the chemical reaction. You really need to use a primer that seals the plywood first or the leveler just won't flow right.