Wood floors are products of nature, and as such are subject to natural forces. Heating your home during winter causes the relative humidity to drop and the air to become dryer. A building in Philadelphia might be as dry as a home in Arizona during the coldest months of the year. When the air becomes dry it absorbs moisture from you, your wood floor and virtually everything else in your home. Dry air can present environmental conditions that are very hard on wood flooring.
Wood is hydroscopic, meaning, when it is exposed to air, wood will lose or gain moisture until it is in equilibrium with the humidity and temperature of the air. Conditions that are too dry can cause as many problems as conditions that are too wet! This is an issue with any wood flooring from any source. Most wood flooring is manufactured to perform best within relative humidity (RH) ranges of 35% to 60%. This just happens to be the same comfort range that most humans enjoy. It is important to run heating and humidity control systems year round to protect your wood floor, even when you are on vacation. Some species and formats are more susceptible to damage from excessive drying than others. For example, Oak will tend to perform better than Maple and Hickory; Vertical Grain Bamboo will tend to perform better than Horizontal GrainBamboo. Generally, engineered bamboo or Cumaru (Brazilian Teak) are not recommended in dry climates unless humidity conditions are carefully controlled. Maple and Beach are somewhat unstable as well.
The guidelines below may help prevent problems.
- Use Humidifiers: The best way to avoid problems caused by excessive drying is to regulate the moisture in the space with humidifiers, which should be functioning throughout the life of the floor. (Don’t turn them off if you are away from home). Most flooring manufacturers require that humidity be maintained within certain levels (usually 35% to 60%) in order for the warranty to stay valid.
- Avoid Sudden Humidity Change: If the wood takes on moisture and is then subjected to its normal dry conditions, the rapid drying may damage the floor. Painting, plastering, or anything else that artificially adds moisture to the space should only be done if dehumidifiers are in place to remove that moisture from the air before the flooring has a chance to absorb it.
- No Wet Mopping: When floors are wet mopped in a dry climate, the dry wood will absorb moisture (causing expansion) and then shed it very quickly (causing shrinking) once mopping is complete. This rapid change in dimension of the planks can cause cracking and other damage. To clean the floor, use a lightly damp applicator that does not allow moisture to sink into the seams.