Had a real 'aha' moment on a job in a 1970s split-level in Cincinnati

The main floor was fine, but the sunken living room had this weird, uneven concrete slab. My old boss would have just padded over it, but the homeowner pointed out a dip you could feel. We ended up scribing and shimming the tack strip in that one corner with some 1/4 inch plywood scraps, and the carpet laid down perfectly flat. Anyone else run into weird subfloor issues in those old split-levels and have a better fix?

4 comments

4 Comments

felix4144mo ago

Read about using self-leveling compound on those slabs.

elliotm573mo agoTop Commenter

The product sheet for LevelQuick says you need a primer and it only goes up to an inch thick. If your floor drops two inches across the room, you're looking at multiple pours with drying time in between. That's a ton of bags, and the cost adds up fast. You'd also have to build a dam at the doorways to contain it. Is that really easier than just framing a new subfloor on top?

brianreed4mo ago

You're suggesting self-leveler on those slabs, @felix414? The amount you'd need for that kind of slope would cost more than the house.

harper9141mo ago

elliotm57 brings up a good point about the cost of self-leveler. I've been down that road before. If the dip is just one spot, scribing and shimming the tack strip is the way to go. But if the whole slab is wavy, you're better off floating a new 3/8 plywood subfloor over the whole thing with some construction adhesive. That's what I did on a 72 split-level in Cincy that had a two inch drop across the room. Way cheaper than a ton of LevelQuick and you don't have to wait for it to cure. @brianreed's right about self-leveler being pricey on those older slabs. Sometimes the old-school framing fix just works better.