Why do hardwood floors sometimes squeak?
In order to produce a squeaking sound, a certain amount of movement must be present. As stated by the National Wood Flooring Association (NWFA), squeaking results from movement of the wood flooring system, subfloor system or underfloor supports. It can also result from inadequate or improper nailing, from a weak subfloor , or from the floor being subjected to excessive moisture or excessively dry conditions. These conditions can be repaired by screwing the floor down from below or by strengthening the subfloor . Relative humidity in the home should be maintained within recommended levels (45% to 55%) since too much moisture or dryness may also cause squeaking.
