I had some 3/4" prefinsihed brazillian cherry hardwood flooring installed in a house that I am building.

The installers in one of the rooms that was not square did the install on a diagnol. they used a spine near the middle where they changed direction. It appears they didnt hand nail the groove (or at least nail it enough) where the spline is. Floor looked fine when installed and for some time after. However since the house is not occupied my wife turned the AC way down two weeks ago. A slight cupping is present in the two boards that were splined together.

What is the recommended method of fixing? I believe with proper HVAC usage the problem will go away. My issue is that I am seller the condo and the buyers are rightfully concerned.

The spline is near center of room so I would like to try and avoid ripping 1/2 the room out. I would imagine that someone could drill a few small holes from top, nail it down and then color match the putty that coverse the holes? It is one board, and maybe 8 feet along that spline that has issue. It is cupping up a very small amount, you can notice it when you walk over it but it is bairly visable to the eye.

We both want to close in two days so right now I am trying to come up with an idea for a solution and a guess of the cost so I can offer them a credit.

Any ideas of a fix for this and what it could cost?

It is possible that the installer didn't nail into that spline to anchor down the backside of those boards and now they are tenting a little. I'll bet it is NOT true cupping, which is moisture related. At this point, you suggestion of face nailing makes the most sense. Either that or taking out the boards that are tenting and replacing them by gluing in new boards. And BTW, face nails in the middle may squeek and not keep those boards down all that well. Trim head screws will work much better but leave a slightly larger hole to fill. I would charge a minimum trip charge to screw down those boards and color fill the holes, with NO warranty that the fix will work or be permanent. My minimum: $125.00

Tenting is a good word to discribe. This tenting is only happening at the spline. I am 99% sure that is what they did. If I remeber they had a straight edge on the first board and then worked toward the corner. They then removed the straight edge, glued in a spline and went the other way.

I would be willing to cut out the bad baord. However in doing so I would then be forced to glue in the new board or only end nail. Would that be a better fix then face nailing or using trim head screws?