I had a red oak 3/4 inch hardwood floor laid a month and a half ago. Laid down 1100 sq feet, glued on a concret slab of which is 30 years old. Slab appeared dry and had no water leak ever in this house. House is under centerair with double pane windows. Approx a week after the floor was laid, left for a week on vacation. When I arrived back home, found the living room floor raised about 4 inch in a stip down the middle, three feet wide. Called the floor installed who quickly arrived and took a stip our of the center of the peak and the floor laid down. However, upon futhur inspection throughout the house, found four area that were raised and when tapping upon them, a very hollow sound came from it. Also, have found what appears to be slight cupping throughout. While this does not look too bad as it gives a look of something laid long, long ago it is of concern to me as it might get worse(?). Our floor installer stated that he will take the areas that are raised out and laid new wood and refinished. Are we on the right track? johnj.

Let me guess...


Solid hardwood, not a cross-ply engineered.

While you were gone, you turned the HVAC system off or altered the settings from the time the floor was acclimated and installed. Thus altering the humidity levels, making the floor gain moisture.


My money is on a solid over concrete, with high MVE

Thank you for answering me. While on vacation the HAVC was set at 77 degree and stay that way. However, during the instattion, our floor guy had us turn off the HAVC a couple of time, especially during the periods of sanding. I can not remember if we had much rain during the time but it has been very dry here(east of Houston, Tx.), for week. From what all I read the floor can be 1) repaired, 2)maybe and 3) ripe it up. Is there some way that I can tell if it can be saved? Can not afford to ripe up a new floor. Pocketbook would cry and wife would kill me! john j

I recall seeing a gluedown LL job a year ago that did the same. Moisture content(MC) of the material was 15%--slab MC was fine, expansion areas fine. What kind of adhesive was used? Color? Is it tacky with little specs in it?

Get a hanky for your pocketbook and you might want to buy a burial plot while your spending money.


What do the installers say about it?
They are the professionals, and should know exactly what happened, to make their installation fail.

You do realise, there is a new warranty law in Texas!!! They can no longer tuck there tails and run. I'd be asking for it to be fixed. They accepted the conditions it was installed.

Oh, and by the way. It is not recommended to glue a solid hardwood, directly to a concrete foundation, or cupping and buckling will happen(sound familiar)

Installers are NOT supposed to glue solid wood flooring directly to concrete. Exception is solid parquet. All other solid is supposed to be nailed per NOFMA and NWFA specs. I can't believe there are people out there doing this. Whom do we have to fault? Adhesive manufacterers who make false claims? Some flooring manufacterers? I don't know where this idea came from? It is doomed to failure every time. This is why engineered floors were developed; to glue to slabs. Any installer who trys to install this way should be made to EAT the entire job and redo at his expense. No excuse for stupidity with all we know. Nuff said!

You go Gary! Some of the things Im seeing done and recommended on these boards(not this one) are pitiful and a black-eye to the industry. Probably been going on all the time, the internet just highlights it. I do think that some of the prefinished manufacturers are pushing ill-informed, faulty practices to sell more flooring for situations they couldn't otherwise sell.

Solid 3/4" flooring should NOT be glued directly to concrete-except for shorts.

I have to agree with Gary and Marco. They hit the nail on the head.
The urethane adhesives do not act as a moisture barrier... they simply do not degrade on concrete with high moisture content.
Sorry, you have a problem that will worsen.