We bought our house 10 years ago. At the time we checked the crawl space for moisture, as this is a low area. Things looked ok but we decided to put a vapor barrier down. The past few years our floors have become very uneven. We had our front door replaced at whic time the repairman discovered our foundation blocks did not have a "cap board". Could this be what is causing the uneven floors. Please tell me what can be done.