Hello All,

I'm a first time poster here because unfortunately I have a problem with some wood floors that were installed last year. I am trying to determine if this is a mistake by the installer or if it is just bad luck and circumstances. The contractor has stated they will "stand behind their work" and implied they will fix it at their cost, but I don't want to wrongfully hold him responsible. That said I don't want to pay to have the floors sanded and refinished due to poor workmanship.

Background - the home is 10 years old and had about 1000 sq ft of original White Oak wood floors in the kitchen and living room. They were showing some wear to the finish and we decided we wanted to have them refinished. While we were at it, my wife decided she we wanted to convert the previously tiled 1500 sq ft of entry hall, dining room, guest bedroom and hallway to the same Oak wood floors. This way we could do it all at one time. This would involve "splicing" in the new floors to the adjacent "old flooring" in a couple of locations.

After interviewing several contractors we selected one we were most comfortable with. We arranged to be out of the house while the work was done in March of 2018.

The installer that was subcontracted brought the new boards to the work site and installed them within 24 hrs. There was no dedicated in home acclimation period. After the fact the installer and contractor claimed that they let the floors acclimate after they were cut and installed but before any finish was applied. In other words, they say they installed them immediately but waited 3-5 days before finishing them.

In the months that followed we immediately began noticing cupping of the new floors, most pronounced at the junction of the "old" boards in the living room and kitchen and the new boards in the dining room, but the cupping was present throughout the new flooring.

The contractor and builder made multiple attempts to look for a leak or source of humidity, including running pressure tests of the slab plumbing. Multiple humidity checks were done by multiple parties with no clear determination of a cause. They did determine there was no moisture coming from the concrete or subfloor and there was no apparent leak anywhere.

They then speculated that perhaps high humidity in the home was solely responsible. They have left humidity sensors in the home for the last 8 months and while we have on rare occasion seen humidity as high as 58% (one time) we rarely see it over 55%. We will of course be monitoring it over the coming spring to see its impact.

This makes me wonder though - if the culprit is high room humidity, why do only the new boards cup while the old boards do not? As the Winter months have come the cupping improved as the cupping "laid down" but it did not go away altogether and we are expecting it to return with Spring humidity. I have attempted to link two pictures below that show the cupping in the "new boards" of the dining room floors at the bottom of the picture with the apparently normal "old boards" in the living room at the top of the pictures. This archway is the abutment of the two sets of boards.

The contractor has stated and implied that they will fix this at their cost. I want to do right by the man and if this isn't his fault, or at least not bad workmanship or installation practice, I don't want him to bear the burden of the cost alone.

Also the contractor is recommending we install a whole home dehumidifier (at a cost to me of $4,000) to help prevent this again and want to be sure this is necessary given the fact that the old floors don't seem to cup regardless of the in home humidity.

Any help or opinions would be appreciated. It is obviously a bad situation, and while I want it remedied, I don't want to be unfair to the contractor or installer.

Thank you all for your help!

I couldn't figure out how to embed the images but here are the links to the photos on imgur:

https://imgur.com/7RKWHcL

https://imgur.com/KbkP4J4

Any changes to the environment under the new floor?

It also appears from the small pictures it could be a wider plank than the original?

The boards are the same width, I think the perspective is giving it that look. They are solid and are nailed down to plywood laid over the concrete slab. No initial measurements of humidity were documented - the installer just says he checked them and they were "within range".

The only environmental changes would be the normal cycling of the air conditioner. We feel very confident there are no tiny leaks in the plumbing or foundation.

Thanks for thinking on this with me!

One hint to who has made the problem is to measure across ten boards of the old floor and ten boards from the new floor. If the old flooring was kiln dried to the same moisture as the new flooring before it was laid and was acclimated before it was installed it would be a wider measurement now, which shows no cupping. The old flooring which is flat now may have been acclimated after laying and before sanding, and had small cupping, this could have been sanded flat. I think that if the new flooring was sanded again it would stay flat without needing to install a whole house dehumidifier. A dehumidifier may cause gaps in the old floor, too.
A moisture reading from a wood moisture meter before the new flooring was laid, comparing the moisture content to the flooring that was existing and acclimated helps the mechanic decide whether the new flooring is ready to be laid, or whether it needs to have small spaces between the boards that will tighten up after the flooring is down. You can install wood that is too dry, if you use a meter to compare, by nailing the floor loosely in anticipation that it will swell a little after it has fully acclimated. Did the moisture meter get used? They are a good investment.

I imagine the planks are the same width if they got laced in.
Acclimation of any wood floor needs to be done prior to installation. Period

Then yes, many installers let it sit prior to sanding and finishing. But as far as acclimation goes they are on the hook. Installers are supposed to document the site conditions or else how do they prove what they were at time of installation.

You should be able to find a flooring inspector here http://www.ifcii.org/by-state/