Q. We just had a new maple floor installed by aThe floor was sanded and sealed with an oil-based polyurethane, then coated with two layers of a waterborne finish. I liked how the floor looked after the sealer was applied, but when I came home from work after the waterborne coats were down, the floor looked blotchy, with irregular areas of clean white maple right next to sections that were amber. Is this normal?
-Anne K. by phone, August 18, 2012
A. After asking the caller a few questions and and requesting a few photographs, we figured out what happened here withfloor finishing job. I asked if her contractor had abraded (scraped away) the coat of oil-based sealer before the first coat of waterborne was applied, and she confirmed that he had.
This turned out to be the source of the problem. Screening an oil-based sealer isn’t necessarily a bad thing, but it appears that the sealer was over-zealously abraded in this case, which cleaned some of the floor to bare maple, leaving the floor blotchy.
If the floor had then been coated with another layer of an oil-based finish, the client may have never noticed anything. But the sealer was coated with a waterborne finish, which, unlike the oil-based sealer, has no color. So the contractor, in effect, sealed in the blotchy effect with two layers of clear coat. This floor will have to be resanded to bare wood and all coats of finish reapplied to correct the problem. Preventing this problem is relatively simple: if you switch to a clear finish after applying a layer of amber finish (or stain), be very careful to keep the colored layer intact if you abrade it.
If you're concerned about how to finish your floor and what to use, talk to us. We can guide you in the cleaning up and getting ready for finish process, which finish to apply, and how to do it. We also sell all the finishes you need here in the store at Pete's.