Spent the weekend ripping out my daughter's flooring and learned a lot about persistent odors

We had that exact "doughy" scent in our 1970s split-level. It hit us every time the humidity spiked above 50% in the summer. I spent months convinced it was a dead rodent in the wall or maybe a slow leak from the guest bath next door. It turned out to be the yellow mastic they used for the old linoleum tiles buried under the laminate floors.

I did something similar to your fix but used Zinsser B-I-N shellac-based primer because the oil-based options were taking forever to dry in that basement air. I ended up doing three thin coats on the concrete after a heavy scrub with a TSP substitute. Even after the primer, I could still catch a faint whiff of it until I put down the 2mm foam underlayment and the final flooring.

It relly is wild how those old adhesives react with moisture over time. We spent weeks worrying about the foundation when it was just 40-year-old glue off-gassing. I’m glad the Kilz worked for you because that peace of mind makes all that back-breaking scraping worth it.

I actualy had a similar Play-Doh smell in my home office, but sealing the slab didn't do the trick for me. My house was built in the late 90s, and after I ripped up the carpet and used a concrete sealer, the scent was still there every time the sun hit the far wall. It drove me nuts becasue I'd spent a weekend on my hands and knees scrubbing with Goof Off and TSP.

It turned out the smell was actually coming from the door itself. The previous owners had installed a cheap, hollow-core composite door that was off-gassing some kind of urea-formaldehyde resin. Whenever the room got warm, that doughy, chemical odor woud just pour off the door's surface. I swapped it out for a solid pine slab from Lowe's and the smell vanished within forty-eight hours. If you've sealed your floors and still catch a whiff on hot days, definitely check your interior doors and the trim pieces.

If you’ve alredy sealed the slab and you're still worried about any lingering scent drifting into the hallway, you shold check the actual door. Those cheap hollow core doors act like sponges for chemical smells over time. I’d swap it out for a Masonite Safe 'N Sound solid core door. It’s got a much tighter fit and the density helps block any residual off-gassing from the room. We put them in our basement to keep the damp smell from traveling upstairs and it made a massive difference compared to the builder-grade stuff.

This is so helpful becasue I just joined this group to learn about door seals! I'm currently obsessed with how you guys fixed that smell. Since you mentioned the laundry room wall, does anyone know if a heavy-duty weather strip on the bottom of a solid wood door whould help with soundproofing too? I'm trying to turn my spare room into a music studio and I'm worried about the noise leaking out as much as the odors!