Polyurethane peeling in some of the joints

Q: We had our hardwood floor sanded, stained and polyurethaned in May and now in March (less than a year) they are peeling in some of the joints, and the joints are now white in color. what would cause this and how is it fixed?

A: There are so many possible causes for this, without knowing what finishes they used, how they applied them, and a host of other elements I can only wager a guess. It sounds like during the heating season your floor, because of low humidity has shrunk a bit, and the finish cracked on the joints. The peeling is at the joints, not over the entire floor.

The fix is to have the floor buffed really well, paying close attention to board edges and apply another coat. Any gaps should be filled first. Try to keep a relatively stable relative humidity in the house.

Similar Q: I just had my 14 year old wood floors sanded and stained, and 3 or 4 coats of polyurethane applied. There is now peeling at the seams where the boards come together. The floor guy says it is because the floor gives when you step on it. Could that cause the peeling?

A: If there is significant flex the finish will stretch and then break and perhaps chip, but not peel. In my opinion a more likely reason for peeling on board edges would be contaminants such as wax bleeding up from between the boards, or if there is a lot of movement from one board to the next, the mans polisher probably went over top but missed abrading those edges and he hasn’t gained adhesion.

(After further correspondence…) 3rd A: The problem I am having with their explanation is that you can pull the finish off in the middle of the board with a piece of scotch tape. This is totally unrelated to the movement of the boards and would seem to indicate lack of adhesion in general across the floor. I have seen tape pull of the top layer of water borne, but I’ve never seen it happen to oil modified. However, when it happened it was because the workers taped the floor around the perimeter of the rooms soon after the coating was applied (not cured) and it was in place for days before they started trying to remove it. It wasn’t a case of applying a piece of tape and then pulling it off right away with the floor finish stuck to the tape.

I can’t question the ability or integrity of the company who did the work. After 35 years I know sanding, staining and finishing is so hard and technically difficult, sooner or later a job will go south. I would think that if they care about you, their customer, care about the type of work they do, and want to have a good reputation, they should try and make this right even if it means starting over. That really seems like the only option to fix this. Putting another coat of finish over top of one that is not adhering is not going to fix the problem.

You would probably be well served if you could find someone local to provide you a second opinion with a home visit.

Similar Q: What can be done about white lines in between boards of Walnut wood flooring?

A: Difficult to say. What caused the white lines? If the boards shrank and stretched/cracked off the finish you will need to control the environment and humidity or lack of it. A buff and re-coat may get rid of the lines.