We have a house, circa 1940, built on a crawl space. The house has original oak floors. We recently did a major renovation/addition that was completed in February 2006. It was necessary to install new wood to "repair" where walls had been moved. The floor company did a fine job repairing the floors and the entire house was refinished and stained. Until recently, it was difficult to determine what wood was new versus old.

A few weeks ago we noticed that the new wood is beginning to "cup" or raise along the seams. The old wood is as smooth as ever. I understand that cupping is commonly caused by humidity issues. However, it seems to me that the old wood would also be cupping if moisture or humidity was the cause. Would it be possible that the new wood was either wet or the process of squeezing it into repair is causing the cupping?

I have left messages for the flooring company but they have yet to see the floors. I would appreciate any insight into what I should expect them to say and if this is their problem or mine. Also, should I insist that the floors be refinished or does the new wood need to be removed. As you know, this is such a messy process since they will need to blend the stain.

Thanks!

There are several possibilities on this one. More information would be helpful. Is it a full 3/4" T & G floor, or a thinner strip floor with no T & G , ? Was the repaired area glued into place, or face nailed, if glued what type of glue? Was a moisture barrier installed under the repaired area's. If it was glued in, I doubt a barrier was put in first. There is probably a 15# felt paper under the old wood to restrict the moisture from the crawlspace from coming up into the wood. The new area, glued or nailed, may have nothing under it allowing the moisture vapors to travel up into the wood, thus causing the cupping, but this is just a possible theory.

Thanks for your reply. 3/4 inch t&g, nailed. I'm not sure if felt or another barrier was used, since I was not home when the wood was repaired. I would hope that they used whatever was customary, since they are allegedly an upscale flooring company.

My take on it...


The subfloor is too wet and always has been. The original flooring is cupped and always has been. The cupping has been sanded flat. Now the new boards are gaining that same moisture on the bottom of the board, and showing the same cupping that was present in the existing floor at one time, before it was sanded flat..

You understand what I'm saying.