Q: We’ve had a decorative wood floor in our dining room for about 18 years. installed by a local guy, with pickled ash finish and a dark cherry perimeter. The wood was prefinished when we installed it. Today we picked up a cardboard box off the floor, and the finish seems to be peeling off the dark cherry. It doesn’t seem to be caused by the box (it was there for a day and was heavy, but no residue on it). The only thing I can reason is that we have skylights above the dining room and they are unobstructed to the sun, perhaps ageing the finish. What happened, and how do we fix it?
A: This is quite a mystery, isn’t it? The sun shining through your sky light didn’t peel the finish in 18 years and I know of no reason it would suddenly do that. The card board box wouldn’t cause this either. At least not on it’s own. Unless something was spilled inside the box or at some point the bottom of the box was set onto any chemical which would attack polyurethane coatings. Things such as strippers, acetone, perhaps nail polish remover? If this is restricted to one or two boards I would wipe them down with a wet cloth to neutralize anything which may be on the board. I would gently but thoroughly rub the entire board down with fine sandpaper or other appropriate abrasive. This scratches the existing coating allowing adhesion of a new finish coat. Apply a thin coat of polyurethane with the same level of shine. If a second coat is needed, repeat the process.by