Thanks jfcwood. The color and finish are gorgeous. The color is a custom stain that he did for us on-site. We love it.

The wood was acclimated for 16 days (wood delivered and set in that exact room on 2 May, he started the install on that room on 18 May; I have all this marked on my calendar). I should say, I am 95% sure it was this wood that was used. Long story short: our installer was going to spike in new flooring in our old wood floor in our kitchen and dining room, but when he started the project, he discovered very shoddy workmanship on the current wood floors we had (T&G going to wrong way, two types of wood used, etc), and urged us to pull up our current wood and install new, vs. refinish it. So that added $$$ and time, and led to a sort of emergency supply of wood that wasn't well acclimated. I think that was only used in the kitchen and dining room though. That's a big part of the reason our budget doubled too.

I don't know anything about the moisture readings. :( I had no idea about how risky crawlspaces were for wood floors until two days ago when I started poking around online as to why this could be an issue in this room only. He for sure knew there was a crawlspace, because he was the first installer we got a bid from and was the one who told me how nice it was that we didn't have to put a subfloor over concrete because OF the crawlspace.

I feel like I do my research and am borderline anal on these types of things, but I just had no idea of any of this until a few days ago. I ask questions, take notes, research, I try to learn as much as I can about things before I make decisions. I'm just sick about it. It was such a big thing for us. :(

Anyway, thanks for the response.

Since the cupping is only happening in the one room over the crawlspace, that ought to lead you and your installer on the path to finding out why the floor is cupping. You most likely need to mechanically dehumidify the crawlspace to equalize the humidity levels between the crawlspace and the living space.

I've seen this many times and it is almost always a problem with an elevated humidity level below the floor construction. Simply venting a crawlspace doesn't always work in these situations, because moisture--laden air will condense on cooler surfaces and cooler wood surfaces then wick up that moisture. Conditioning the space is the only way to keep levels somewhat constant.

Hope this helps.

Thanks. I agree glennsfc. But shouldn't the installer have told us about this possibility beforehand? That's the thing that upsets me the most. It seems like such a common problem and if he addressed it before I doubt we would have done that room, which was at the end of our wish list anyway. We've spent so much on those floors, trim, all the costs that add up when doing these projects and the idea of spending more on something I feel like I should have known about already as a factor in the flooring just makes me upset. Am I expecting too much from the process?

Well...yes and no. Some floors do well over unconditioned crawlspaces. How a wood construction floor system performs is dependent upon jobsite conditions, the climate conditions of the jobsite and the type and amount of air conditioning employed to keep the living space reasonably constant in temperature and humidity.

I have seen floors that were perfectly happy cup when the HVAC cooling was engaged during the summer season and then return back to normal when the HVAC heating was turned on. Wood flooring is hygroscopic and will sometimes exhibit cupping, crowning (the opposite) and gapping during the heating season. These things move with changes in conditions.

Your floors look splendid, except perhaps for the slight crowning in that one area.

BTW, in what region of the country do you live...and what has been the temperature and humidity index generally? And, how much indoor air conditioning have you employed?

Look for a plumbing leak.

What type of flooring was replaced? If it was wood, you did not have this problem before?

Very beautiful floor.

Thanks for everyone's responses, I really appreciate it.

I might be getting closer to the problem...got inside the crawlspace today and found that several strips of insulation that were between the ceiling joists had come loose and were laying on the ground. Not one bit of water down there, no leaks, nothing, except that insulation. I could see what I guess was the bare subfloor above me, wood floor nails exposed and all. And the parts of the floor above that are cupped the worst correspond almost exactly to the areas of insulation gone. So I'm thinking we'll replace that insulation ASAP and take the opportunity to also put down new poly and maybe put some rigid insulation on the walls, too. Floors guy is coming over tomorrow still...I want to see his story about this, whether he took any readings beforehand or checked at all to see if there was a problem with the crawlspace's insulation. I also thought perhaps the insulation was knocked loose FROM the installation. Those machines and hammers can pack a wallop.

I feel a bit better...I had awful visions of standing water and/or a plumbing leak down there. Sheesh.

BTW, we have crazy crazy high humidity right now. I'm in Omaha. AC has been employed almost constantly for a couple of months now. There was carpet there before.

Do you think there's hope of it returning to normal if we address the insulation ASAP? It's only been less than two months. I'm hoping no permanent damage was done.

Cupping will reduce somewhat when the conditions above and below the floor come close to some kind of equalibrium. Once you fix the insulation and the humidity rises a little in your living space, I believe you will see a change. Don't think you'll have any permanent damage...edge crush for example...just not enough swelling of the boards to do that in my opinion.