6 months in new construction, upstairs wood floors popping sounds
I'll try to describe everything as best I can. I would love and appreciate some input. We had a house built in VA while we were still living in NC, so we were unable to keep checking on the house as it was being built. I didn't realize until we moved in that our joist spacing (I-joists spaced 24" OC) was spaced so far apart! Thankfully, our downstairs has 2 subfloors (we were supposed to only have Advantech as the subfloor, but they made a mistake and put OSB down instead. We insisted that they put the Advantech over it. So the floor feels pretty solid despite the joists being spaced so far apart. We have white oak flooring on both levels of our home. There are no noise issues at all downstairs where there are two subfloors. However, upstairs was supposed to originally be carpeted. We changed our mind at the last minute to all wood upstairs as well, but the subfloor is only OSB over the joists spaced 24"OC (didn't realize that at the time. We naively thought they put Advantech upstairs). The first 6 months of living here were fine. Then as the humidity started rising in summer, the upstairs floors developed noises like pops and cracks (sounds really loud at night when walking down the hall trying not to wake the kids!). They have gotten worse and now we have been here a year and it is still bothersome to say the least. I understand that the subfloor and joist spacing is most likely to blame, as I can actually feel some of the boards flexing as I walk. The builder said they cannot warranty against wood movement as the house settles and wood shrinks and all. Hmmmmm. Is there anything that can be done?