Renovating our 100 year old house in the Northeast....
My floors were originally uneven because of old structural issues in the basement that have since been stabilized.

We bought 3" x 3/4" pre-finished red oak (Appalachian Flooring Select Grade). The contractor had the wood acclimating to our house for 3-5 days before installing (June). At this time, our air conditioning was non-functional, so the house was warm (and likely humid). The basement was damp. I do not know if they took moisture readings of the wood (or what the readings were).

We paid extra for the contractors to strategically "feather in" plywood under the hardwood so as to compensate for unevenness in the underlying floor. They floored over some of the original oak floors in some areas, and ripped up the old floors in others.

When they were done, it looked great! My floors were sooo much more level!! It looked and felt awesome! It looked like they had done a great job.

Then we put the air conditioning on 2 weeks ago.

My floors have "tented" up in spots and it's like there was never any leveling of the floors done at all. I thought there must have been a structural problem because it felt "sunken" in spots. It's like each joist underfoot feels like a speed bump.

The contractor said to dehumidify the basement and all would be well. We have been running the dehumidifer constantly and there is no change in the floors.

Now he says that it's just how my joists are, and that my floors were uneven to begin with, "but now they're so much better! We never promised we could make them perfect!"

How should I proceed??

(I also posted this on gardenweb...TIA!)

Sound like conditions for a perfect storm....humidity, subfloors not flat, etc. Contractor should have been more diligent about having the proper conditions. If contractor is not willing to make any corrections I would contact the Consumer Protection Division of your State's Attorney General's Office. They will contact the contractor on your behalf and mediate the situation.

Sugggestion. If you are not familiar with the proper conditions for installing and maintaining hardwood floors, e.g. relative humidity, humidification/dehumidification, moisture content, acclimation, subfloor flatness, etc. you might want to do some research so that when you talk to the installer, AG, or whomever you will have a good understanding of what the proper conditions should be vs what they actually were when the work was done.

You say you are running a dehue in the basement is it big enough for the space? You have to have a pretty large one to work well. The reason you floor is cupping is because you are drying out the top (shrinking it) with the ac and the damp basement is keeping the bottom of the boards at a higher moisture content thus expanding the bottom side only. Does the basement have a finished ceiling is the a/c running in the basement also? If not check the m/c of the wood on top and the subfloor underneath. If the numbers are not with in two or three points then that is your problem. YOu have to have close or equal m/c above and below for your floor to behave correctly and lay flat. How long ago was the floor installed?

Thanks everyone. Hardwood installation was finished early June. I have a 70-pint dehum running now & I just ordered another dehumidifier of the same capacity.

The basement is unfinished (no ceiling) and gets damp (no sump pump/french drain). No A/C in basement. These conditions pre-dated the install.

I don't have a moisture thermometer. Is the problem fixable? Meaning, will the wood floor go back to normal if the moisture levels are brought within points? Should I stop using the A/C on the main floor??

If the floor has cupped or pulled off the subfloor it will not fix itself. Running a dehumidifier in a damp basement is a good idea even if you don't have hardwood flooring. Run the A/C if you want to. Hardwood flooring manufacturers' installation instructions usually tell you what the house's year round humidity range should be to keep the floor happy. Do what the contractor now advises so that when the floor doesn't fix itself and you take action against him then you'll be able to say that you have followed all his instructions. Humidistats are inexpensive. Put one in your house and you'll be able to easily monitor the humidity level.

Just found installation instructions online. It States that wood must be acclimatized for at least 48 hours in climate controlled environment. The contractors had not reinstalled the air conditioning till the end, so I know it was definitely not climate-controlled. It looks like no matter what, my 35 year warranty is voided.

Hadwood Inspection at this point? Or not even necessary?

The flooring should be at the proper moisture content when it is installed. The time it takes to acclimate to the proper moisture content is not a definite number of days. From what you have said the environment was not right. If your contractor isn't going to fix it then you'll have to take some type of legal action against him. As previously mentioned contact the Consumer Protection Division....they arbitrate with the contractor on your behalf.....won't cost you anything.

JimmieM

In all due respect are you a flooring contractor/installer?

If not then you should not be advising as an expert in a field you are not qualified in and certainly advising legal action and DCA involvement when you don't know what the circumstances are and environment of the jobsite are.

This site is not for that.

A contractor has no control of the site after he is gone..heavy rains, increased humidity levels, ground water tables etc are not his responsibility.

You do not know the installer is at fault.

The best advice would be is to get an inspection by a certified wood floor inspector however even armed with that wont change the facts.

The environment below or in the home is not contractor responsibility.

Possibly taking an estimate or 2 and getting a different opinion as to cause and corrections may be useful.

the fact is this..the OP was happy with the work, floors were level to her acceptance, and then something changed.

it wasn't acclimation or lack of that caused this.
it was the balance of MC between substrate and the flooring itself which may have been ok at install and changed after..or not..we can not make that determination from our computers.

James, I was responding based on the info provided by the poster. Based on that info would you have done the install? In your opinion will running a dumidifier correct the problem as described?

if the flooring has in fact buckled no..a dehumidifier will do nothing.

if they are simply cupped, then it is possible they can self correct once the imbalances have adjusted to normal ranges of eachother.

this assuming the cupping was not exorbitant and extreme.

as for installation..if my readings said the substrates were ok, then yes I would install..

installed plenty of flooring into uncontrolled environments.

humidity is humidity and flooring will always be exposed to it.

no one lives in perfect environment settings 24/7/365

I find this to be a double edged sword. All installation standards state the HVAC should be up and running days if not weeks prior to installation and acclimation.
But then there are other mitigating circumstances where the site conditions may change that the installer/contractor was not aware of, or could not possibly predict.
In this instance, no HVAC at time of install is on the contractor.