Cupping

Wood takes in water and swells. When the bottom of a board gets more moisture than the top, the board swells more on the bottom and its edges curl up. Run your hand across a cupped floor and you can feel a ridge at every seam. In low light you can see the rows of shallow dips.

The moisture can come from many places. A leak, a wet crawl space or basement, a damp slab, or very humid weather can all do it. The cause has to be found and fixed first. Otherwise the boards will keep moving.

A screen and recoat only renews the clear finish on top. It does not change the shape of the wood. Coating over cupped boards would leave the same ridges, just shinier. That is why warped or cupped boards are on the list of floors a recoat business walks away from.

At the estimate, look along the floor at a low angle and feel the seams. If the boards are cupped, tell the homeowner up front. The floor likely needs a flooring pro to fix the moisture, and then a full sand and refinish. You can refer the job to a local refinisher.

Being honest about floors like this builds trust. The homeowner may call you back for a recoat once the floor is fixed, or send a neighbor your way.

Recoat, sand and refinish, or replace a worn hardwood floor? Prices per square foot, days of disruption, how much wood each uses up, and what the NWFA recommends.