Warped!

[rocketman]

Upon returning home at the end of summer, the hardwood on the stairs was warped and buckling, but not in the main room. The only difference after 20 years is that the occupants brought in air conditioners for the summer -- could that be the cause?

 

[Ernesto]

Upon returning home at the end of summer, the hardwood on the stairs was warped and buckling, but not in the main room. The only difference after 20 years is that the occupants brought in air conditioners for the summer -- could that be the cause?

Yes absolutely. High relative humidity and heat can cause that. Had you been home you could have opened up windows and run fans if you don't have AC.

 

[rocketman]

In my case, this is the first summer that there was a/c. Could a/c be the cause?

 

[JIMMIEM]

In my case, this is the first summer that there was a/c. Could a/c be the cause?

what's beneath the stairs? basement? a/c in basement or just rooms above? all stairs warped? where's the house? what type of wood?

 

[rocketman]

The stairs lead to a finished basement where there was no a/c, although immediately below the stairs is a closet which includes the sump. Most stairs are warped -- oak. The house is in Quebec.

Could it be, when the summer occupants who brought portable a/c with them and left a week ago, that the sudden increase in temperature had an effect over the course of a few days, whereas the decrease at the beginning of summer with their a/c did not?

 

[JIMMIEM]

You said the stairs are made from hardwood flooring? Are the boards cupped? Cupping is due to a difference in the humidity above and below the flooring. When the humidity above the floor is lower than the humidity below the floor the floor boards will cup. If these are your conditions then this could be the problem. Also, is the closet with the sump damper than the rest of the basement? Does it have good air circulation? What has the weather been like in Quebec this summer....specifically the humidity? If you've had normal weather conditions then the a/c on the first floor may have taken the humidity to a lower level then it's ever been at in the past. How warped....can you post a picture?

 

[rocketman]

There is no particular dampness below the stairs. That hasn't changed in 20 years of this hardwood flooring. The only change is the temporary introduction this summer of A/C. This month has been typically humid and hot.

 

[JIMMIEM]

The edges of the stairs that are cupping typically have less holding them than the flooring in the room and would be more sensitive to a difference in humidity above and below......I'd vote for the a/c as the culprit.

 

[rocketman]

Thanks

 

[Ernesto]

Ah yes, looks like JIMMIEM is correct, its the reverse of what I thought. The AC is pulling out more moisture than the woods accustomed to.