Winter is here, which means that here in Connecticut, the temperatures are dropping and the indoor heating systems will be kicking on. Soon, concerned homeowners will be calling us and asking questions about seasonal changes in their wood flooring. Seasonal related changes are one of the most common complaints homeowners have this time of year.
Cracks between boards are one of the complaints from homeowners with hardwood flooring. These cracks will show up in the winter months and fade away in the summer months. Properly made and installed flooring is expected to have seasonal cracks between the boards of the flooring.
Seasonal cracks in wood floors are caused by a moisture change in the environment. In the winter months, when the air in a home is heated, the relative humidity levels drop. Eventually, the moisture within your wood flooring is naturally drawn out of the wood and into the air. As the wood loses moisture, the boards begin to shrink and gaps begin to appear between the boards. This is completely normal and is directly related to the reduction of moisture in the air within a home. Once the seasons change and the indoor humidity naturally rises, most of the seasonal gaps will disappear.
The width of boards, the species and how the wood was cut from the log can all affect how dramatic of a change will occur from seasonal changes in wood flooring. In general, how much solid hardwood flooring shrinks is directly proportional to its width. For example, in identical scenarios, an 6” wide red oak board will shrink twice as much as a 3” wide board of the same cut and species. In addition, woods with a lighter grain (example: maple) or lighter finishes (example: water-based finishes) will give the appearance of the crack being larger due to the dark contrast between the board and the crack.
To minimize seasonal cracks, there is really only one way to do so. Keep the moisture content in the wood consist year-round. We recommend maintaining a normal indoor relative humidity between 45% and 55% throughout the year to minimize the natural expansion and contraction of the wood.
Keeping a consistent moisture level can be achieved many ways. One of the most effective methods, installing a humidifier on your furnace unit. A humidifier will introduce moisture to the forced air system and then throughout the home. Another method, is running a portable humidifier and monitoring the moisture manually. Other techniques include: leaving bathroom doors open while showering, opening windows when it’s raining, hanging damp clothes around the house to dry, and boiling water on the stove. If you introduce an excessive amount of moisture you will cause damage to many areas of your home. Always monitor the moisture level in your home.