Your hardwood floor during the dry season
During the winter, when homes are heated and the air is dry, wood flooring loses some of its moisture and contracts or shrinks as a result.
Hardwood flooring dryness problems:
It is normal that when relative humidity is lower than recommended, wood plank shrinks, therefore thin gaps can appear between wood planks. Even if the right term to use is gaps, these small gaps between the wood planks can sometimes be called cracks or spaces between wood planks by consumers. Having gaps between your wood planks is normal, and a homeowner should be prepared for it to occur. Once humidity levels rise again, the hardwood floor will expand and most gaps will close up again.
– Splits & Checks
When the wood is faced with extreme conditions, it can be stressed beyond its limitations. Therefore the wood weakens, making your hardwood floor more brittle and increasing the likelihood of damage or splintering. The boards themselves may split, check or crack in the center or at the ends, or both, along the grain, damaging the finish. This damage is permanent, because your hardwood floor finish is cracked—your wood is no longer protected.
One of the easiest ways to avoid wood flooring installation failures is to have a clear understanding of relative humidity (RH) and its impact on wood. Wood is a hygroscopic material, which means that it will swell and shrink as it absorbs and loses moisture. This will happen as a direct result of the environment it is placed in. The environmental factors that affect wood flooring are the temperature and RH of the surrounding air.
Acclimation is the first step in managing how RH affects wood. Acclimation is the process that we use to bring wood to the moisture content that coincides with the expected in-use conditions of the facility in which it will be installed. This is known as bringing the wood to equilibrium moisture content (EMC).
As a general rule, wood floors will perform best when the interior environment is controlled to stay within a relative humidity range of 30 percent to 50 percent, and a temperature range of 60 degrees to 80 degrees Fahrenheit, but optimal conditions will vary in different regions based on average moisture content and RH.