Wood flooring expands and contracts with changes in ambient temperature and humidity. This is normal, but one way of minimizing it is to ensure that rooms are well ventilated.
There are different types of warping:
for example, if it’s concave, it may be caused by:
- moisture rising up through the underfloor and causing the strips to swell,
- or by ambient air drying the floor out and causing shrinkage between the strips.
Convex warping is often caused by humidity in the air.
Warping due to fluctuations in ambient humidity can be corrected using a humidifier or dehumidifier, as appropriate.