I need the “definitive” answer about hardwood flooring. The prefinished manufacturers say that the prefinished is the only way to go, better finish, stronger finish, lasts longer. The unfinished manufacturers say finishing on site is the only way to and that water will get in the cracks of prefinished flooring and ruin it. Which is correct? Is the prefinished flooring with UV and 7 coats of urethane, complete with aluminum oxide a better finish than what can be put on site? Does water get into the cracks and ruin it?
You have heard the correct answer in both cases. Prefinished floors with a factory applied conversion finish should outlast most all site finishes. But they too will get scratched, and need a fresh coat of finish, every 5-10 years, depending on use. But, you may not ever be able to get any finish to permanently stick to these highly cross-linked finishes. They are so tough that they cannot be screened for recoating. Instead you will need to use a professional prep wash on these floors, and re-coat them with a catalyzed water base finish. All in all, a very expensive job, and I have yet to see the proof that these systems work in the long run. Ever see a floor’s finish peel, I have, not a pretty sight. And, that is correct that these floors tend to absorb water through the open seams, and age badly as more gunk get caught in these cracks. Even the best of them will seem bumpy underfoot, and the worst of them will develop chips on the edges.
On the other hand, site finished floors are nucance to have sanded for the first time. You will have to vacate the house from several days to a week. With some of these finishes, polyurethane for one, it will take up to a month for curing. And most of the oil polys will smell for about a week after they are finished. Water based finishes dry more quickly, but are pale in color, or have a short track record like the Dura Seal 1000 (see Dura Seal article available in the search box at the top of this web page). There will be a dust cleanup after also. You may find it difficult to find a excellent floor sander, one who will do a stellar job on your floor. Don’t settle for second best, a poorly finished floor is a nightmare that will haunt you every time you see it. I know I’ve heard far too many horror stories, of sanding gouges, and bubbling finishes. But if done well, you will have a glowing, smooth finish, with all the seams level and tight. Very easy re-coat, and I typically get 10 years out of my finishes, and go about 30-40 years between re-sandings. Site finished floors are my mainstay in business, and all my own houses have been done this way.
But you should read my floor maintenance article available in the search box at the top of this web page for the different ways we treat these two different floors. Make sure you also read my article about hiring contractors also available in the search box at the top of this web page.
So, there is no final definitive answer, only YOUR choice based on the best information I and others can give you. I tend be more neutral because I will not sell you a floor from here. Good Luck