Q: This is our original floor (picture included). What do you think caused it to peel like this?
A: Well, it is happening on the edges of the boards. Was this a factory finished floor that has been sanded, stained and finished again? I can think of two things that can cause this. One is contaminants between the boards which react with the finish. I would more expect that to happen with very old floors, which this isn’t.
The other issue is adequate preparation to gain a bond between coats. The finish bridges over board edges from one board to another. If there is movement, especially up and down the finish will stretch and start to crack or peel, especially if there is not a good inter coat bond.
Follow-up Q: No, it’s not a factory finished floor. We saw them finish it 15 years ago. We used radiant heat under it for a few months and we thought that caused it to peel. Ever heard of radiant heat under hardwood causing peeling?
A: No, I’ve never heard of radiant under floor heating causing finish peeling. I didn’t see any gapping of any significance either which would seem to indicate the wood was not suffering moisture imbalances which would have corrected and resulting in shrinkage and stretching of the finish on board edges. Even if that happened, the finish might crack and discolor where it bridges from one board to the next, but why would it peel on the floor surface?