We just moved into a new house and the builder provided us Mercier hardwood flooring upgrade. Recently, there are many cracks appearing on the newly finished hardwood (around 20% of all boards).
We have carefully controlled the humidity (50%) and the temperature (21 C) since we moved in.
Why the cracks are appearing? Is it because of the quality of hardwood boards?

Thanks!
Gavin

When (time of year), where (your city and state), and how was it installed as in glue nail or float? HVAC on at time of install?

They were installed in Jan this year, and we are in Toronto, Ontario. I am not sure how they installed. The HVAC should be on at time I believe. But since it is a new house and had not closed at that time, so I am not very sure...

Thanks!