Fish eye bubbles and sanding sealer on top of polyurethane as a fix

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Q: Please help. We hired a floor refinisher with over 30 years of experience to refinish our 24 year old red oak floors. He is having one problem after another with the finish which is an oil based polyurethane satin finish. He has put on 3 or 4 coats of poly in some rooms and he keeps getting fish eyes, cloudy spots, etc. and debris in the finish.

So, today he decided to put on Zar sanding sealer on top of the room with 2 coats of poly saying that the wood was breathing causing the issues and this sealer would stop it. He intends to come back tomorrow sand the sanding sealer lightly and put a 3rd coat of the Zar oil based poly on top of it. So, that room will have a coat of minwax stain, 2 coats of Zar satin polyurethane, 1 coat of Zar sanding sealer and a top coat of Zar satin polyurethane for a total of 4 coats of finish plus the stain. If this looks good he intends to seal the whole house with the sanding sealer (including the rooms with 3 or 4 coats) and then put a top coat of poly. If he does this some rooms will have 5 coats of poly plus the sanding sealer.


My question is how many coats of poly are too many? And should he have put the coat of sanding sealer on top of 2 coats of poly?


He has sanded between each coat, but I’ve never heard of putting sanding sealer on top of polyurethane before. I can’t imagine this is the right thing to do.
This has been a nightmare. He has been paid in full and we feel stuck. Please advise.

Webmasters answer: Hi, the guy that usually answers is in the hospital and the best I can do promptly is refer you to this stack of fish eye related answers: https://www.woodflooringguy.com/category/sanding-refinishing/problems-with-finish/fish-eye-bubbles/

Hopefully this guy will have the integrity to make it right in the end. Complications are so incredibly stressful for everyone. 

A: I received this late. It sounds like a disaster in progress. I’ve never heard of sanding sealer being applied over polyurethane and I never used the product.  If they had used a reliable finish such as Poloplaz Primero and made sure the area was clean with no air movement until the finish had set up, this job would have been successfully completed and everyone would be happy.

Webmasters note: I would love comments from anyone who has tried sanding sealer on top of polyurethane for this purpose.

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