I have a rental unit in which i refinished the hardwood floors. after 2 years, i applied a new coat of poly on the floors before the next tenant moved in, and now, 1 year later, i notice there are large soft airbubbles along the seams of the planks of wood. i've been told that the newer coat did not bond correctly to the old coat. i really don't want to sand and refinish the floors again. Is there a quick, easy fix that i can attempt? it doesn't have to be perfect and ideally i was hoping i can spot treat it instead of doing the entire area. would you strongly discourage from scraping/sanding away bubble and apply poly just to those spots for a seal?

any suggestions will be greatly appreciated!

I would suggest you have a pro go in there and do it right. It will cost you less in the long run. How much is your time and aggravation worth ? Throwing good after bad. What happens when the finish starts peeling while the renters in there? People try to save a buck, and it ends up costing them in the long run. I'm guilty of that myself. But I have my wife to remind me of my limits

I can't say for sure without physically seeing the floor . But it sounds like you're saying all the bubbles in the poly are along the edges of each board ? One reason for this could be that there is wax or oil soap product residue between the boards.

In general, re coating is only a good idea if you know that the old urethane has zero contaminates on it. If contamination is your actual problem, there isn't much you can do besides re sanding the floor.

If you want to take a shot at scuffing the floor, rent a Clarke square bugger with 220 grit screens and see if you can blend out all the bubbles . If you can, then re coating should be possible.