Our wood floors (3/4" site finished white oak) were installed on top of 3/4" OSB over 24"OC ijoist spacing (we didn't realize this was the spacing until after we moved in, and we wouldn't have even known it was a problem until we started researching our problem). When we moved in the floors were fine, however, 4 months after moving in we started hearing popping whenever we walked on our wood floors in certain areas. The areas have continued to grow over the past year so that the pops and cracks are heard all over our second story wood floor. We decided to go with wood at the last minute (in lieu of carpet) but were never told by our builder that the subfloor was not thick enough over 24" OC joists to properly install. We had a floor inspection done which confirmed that the wood floors were not properly installed according to the wood floor manufacturer's and NWFA's installation instructions. Now what? Does anyone have any recommendatios as to how to fix this problem? The flexing of the subfloor between joists is causing the wood floor boards to pop and crackle. It is so loud that we can't walk down the hallway at night without waking the entire family. Can the subfloor be stiffened by going through the ceiling underneath? Blocking? Or is the only fix to rip out the floors, rip out the subfloor and have everything re-installed properly? The subfloor is glued and screwed to the joists so I'm not sure if that is even possible. Is it? Or should we simply rip out the floor and put in carpet? So confused. The builder wants to do the least possible (they are blaming us for making a last minute change to wood floor) and the floor inspector said they can't make recommendations as to fixes since it is a liability issue. They are only supposed to report the facts. So.....any help? If they had told us that the subfloor was not thick enough during the building process, we would have put the money into upgraded carpet. I hope my post isn't too rambly and that I'm making some sort of sense. Just not sure what to do.....