Q: I have 2″ slat hardwood. Small gaps. I used 3 coats of B*** water based polyurethane 10 years ago. I would like to refinish the floor. I would like to use a thick high gloss like Marine varnish #13. Would the cracks and small gaps show again? If I put down enough coats, would the natural floor movement start the cracks between the slats again, or would it be a solid coat?
A: I don’t think I would use marine varnish unless this is a boat deck. If there is movement in the floor, the coating will eventually fracture on the board joints. Perhaps you need to take a look at a wood filler such as Timbermate. www.timbermate.com
Follow-up Q: (Attached close-up of an interior floor) So, the interior floors with 2″ slats, having some movement and no matter how thick the coating, will eventually crack? Would the Timbermate help in this case?
A: It depends how much movement there is. They say it won’t shrink, crack or fall out. I have my doubts. It is a more robust filler, for sure. But there are limits to everything.