Should the sealer or primer be counted as a coat of polyurethane?

Q: I am having hardwood floors installed. Upstairs he said he put 3 coats, but I think he’s counting 1 coat of the sealer or primer. Should the sealer or primer be counted as a coat of polyurethane? Can you use primer as a finish coat? What I read sounds like polyurethane isn’t that good. Is this correct?

Also, there is only 1 top coat which is gloss. The other or others are semi-gloss. Do I need to have at least 2 coats of gloss? Or is 1 sufficient?

A: I don’t know which products your floor guy is using. However, if he is using a polyurethane based sealer that would indeed be one coat. The purpose of this type of product is to penetrate well into the wood and thoroughly seal it for protection. It isn’t meant to be a ‘build’ coat. One coat of gloss is fine. The one difference I have with him is I apply gloss first because it is generally a bit harder than the softer sheens. Then the final coat is the sheen of choice. So, generally my application procedure is: 1 coat of Poloplaz Fast Dry Polyurethane based sealer, 1 coat Poloplaz Primero gloss. 1 coat, sheen of choice. If they are using good quality finishes, this should be sufficient and give you good service for a number of years to come.

Follow-up Q: The floor guy used D******* High Gloss. 2 coats upstairs, and 3 downstairs. I don’t think DuraSeal penetrates and gets hard enough. The painters got some blue tape on the floor, and it peeled off the 3 layers of poly. The poly looked like when you peel cellophane off sticky candy after it’s been wet. Have you ever worked with D*******?

A: I tried D******* polyurethane once years ago. Didn’t like it’s performance. But there is absolutely no way that tape should have pulled the finish. I’m a member of a flooring forum and this issue came up. So I did an experiment on 2 pieces of oak that I stained and applied a couple of coats of Poloplaz Primero and a pine plank which had 2 coats of Poloplaz 202 waterborne. I applied 2 types of green tape and a strip of Gorilla tape to the 3 boards, pressed it down firmly and left it sit 5 days. I removed the tape without harming the finish in the slightest. My suggestion is that either a contaminant got on to one of the coats of finish and was coated over, affecting adhesion, or there was not sufficient inter-coat buffing done to gain adhesion, which is the more likely of the 2 scenarios.