How long was the flooring in the rooms in which it was installed prior to installation? Was it acclimated and tested for moisture prior to installation?

Thanks for replying so quickly. The wood was in the front room where the problem is manifesting the worst for 2-3 weeks I'd say. That room has pretty much the same amount of light and temperature fluctuation in April as now.

As for testing for moisture, I don't know what that means, sorry. Could you please explain if there's some sort of tool or something I could have used on the new red oak purchase to determine moisture content?

Thanks again...I look forward to more advice.

Whomever did the installation should have left the wood in the room for some period of time to ensure the moisture level in the wood was the same as it would see once installed.

For instance, as an extreme case, if the wood was in an unheated warehouse in the dead of winter, the moisture level in the wood would be very low. If that wood was immediately installed into the house, as it regained moisture from the now warm and more humid atmosphere in the house, it would swell, potentially buckling.

Testing for moisture involves using a 2 pronged probe and sticking it into the wood to ensure the moisture level of the wood is at the proper level. Some woods take a LONG time to acclimate (weeks) to the environment they are in.

I would guess moisture is coming up from the basement into the subfloor and subsequently into the wood. Do you know if a moisture barrier (tar paper or similar) was installed under the floor? You can't really see the type of excessive moisture levels that could cause this. It's not something that would condense or feel wet.

OK,I understand. We indeed have a moisture barrier installed in the basement, which has 9-11 ft high ceilings. It's dry down there, but we are in a humid climate and had lots of rain this past summer. We could run a dehumidifier down there during summers, would that help? Also, how much more buckling can we expect, and how much more time will it take for the wood installed to settle in? Is there anything we can do to remediate the situation except for replacement of the wood & doing those sections over again?

P.S. It sounds like jacking up the house isn't a solution. Should we return the jack posts and 4x4s and do something else? Would it be best to wait and see what else happens, if there's even more buckling before winter sets in? I'm feeling a bit sick to my stomach...are we doomed to have to do two rooms of flooring all over again? :-(

I don't much like this harsh reality, but I do appreciate your advice very much.

Jacking up the house! What?!

The question from hokiez was "Do you know if a moisture barrier (tar paper or similar) was installed under the floor?" Did your contractor install anything between your subfloor and the oak?

I assume this oak is solid flooring. The cupping will probably stop, unless you have a water leak of some kind that you are unaware of.

Clarify some more please, if the board edges are higher than the board center that is called cupping. If the board center is higher that is termed as crowning.

a lot of distributors will moisture test the flooring on delivery. You might want to ask if this was done. The moisture content needs to be within about 4 percent of the subfloor. You have no idea how or where the wood was stored prior to being delivered so the moisture content could be quite high.

Here is my take...

Since the existing is flat, it tells me that the existing was installed at the regions average MC, or gaps were left in it during the installation if it took place in the low humidity season.

Acclimating a floor in a low humidity season, and installing it tight, is just as bad as no acclimation at all.

There is a documented average regional moisture content for wood. Each species of wood has what is called a shrink & swell coefficient. It is a number so you can do the calculations to see exactly what the wood is going to do given a rise or loss of moisture content.

If the wood is acclimated to the heating season or season of low humidity, gaps need to left in the field of the installation, so when the humidity does rise, the wood doesn't compress the edges, in a cupped appearance and eventually buckle if it is excessive pressure. Proper acclimation isn't just sitting the wood in a room. Actually far from it.

I'd say improper acclimation issues, brought on the condition your seeing.

Cupping from a wet humid basement or crawl space, will show up faster then 5 months.

Take all that with a grain of salt... I'm sitting here, and not there with my moisture meters.

I don't know much about this, but I had the same problem, with two different floors. My subfloors were tested for moisture issues after the first occurrence, and none were found. On both installations, I did have a moisture barrier under the flooring. Eventually, the conclusion was that the floors did not have enough room for expansion on the longest runs. Don't know if this is applicable to your situation, but to avoid having to deal with this again, this time I'm getting an engineered floor, which are supposedly more stable than solid hardwoods or laminates.

floorguy

You said "Proper acclimation isn't just sitting the wood in a room. Actually far from it." Can you expand on that?

When would be a good time of the year to install hardwood floors? Assuming you live in an area with all four seasons (Fall, Winter, Spring, Summer).

I did expand on it, read my whole post above.