Q: I’m installing 3-1/2×3/4 maple floors and there is one area of the room that has a hump and is not even. I have already put down new sub floor. Would it be OK to just put shims under any uneven spots when installing the hardwood?
Also, should I nail or staple?
A: I think in the long run, if the hump is a major concern, you should deal with it now rather than using a stop gap measure such as trying to use shims.
The floor is only going to be as solid and stable as what it sits on.
Personally I prefer cleats to staples.