Spending $12 on a hygrometer might be the best investment a homeowner with wood flooring will ever make. While most people wouldn’t even know what a hygrometer is, those who install wood floors are familiar with this instrument. A hygrometer is used to measure the amount of humidity and water vapor in the atmosphere, in soil or in confined spaces.1 Wood is a natural material.

Even when hardwood has been cut into flooring, it is still capable of absorbing and retaining water and water vapor.

How does it affect wood flooring?

Overtime, too much, or too little water content in your wood flooring can cause serious issues. Monitoring your home’s temperature and relative humidity can go a long way toward maintaining beautiful hardwood floors for a lifetime. This is especially true for those who have hardwood floors in their vacation homes.


When your wood flooring was first installed it had to acclimate to your home. This process, sometimes called conditioning, allows the new wood for the flooring to reach its equilibrium moisture content (ECM) within normal living conditions.2 The ECM is an important factor in wood flooring installation since ECM is defined as the point where wood stops absorbing moisture from or releasing moisture into the surrounding air and reaches is equilibrium with the atmosphere.3 If an acceptable ECM is not reached prior to installation, once installed the wood flooring will expand or contract depending on its moisture content.

All wood floors expand and contract to a minimal degree based on the season of the year. However, new wood will have an ECM that was established where it was manufactured or stored for a long period of time. For exotic wood species, from tropical locales, this would usually mean that the wood has a lot of moisture and has expanded in its natural environment. That is why it may take longer for exotic woods to reach their ECM. Conversely, many brands of engineered wood take less time to acclimate due to the manufacturing process.

How to acclimate hardwood

To acclimate wood flooring the floor installer opens the boxes of wood and carefully stacks the wood flooring in the area where the flooring is going to be installed. There it sits for a number of days, usually 5 to 10 days, until the ECM measures within 2 percent of the subfloor.4 This process can get technical, but the bottom line is that if the flooring does not acclimate properly, serious problems can occur after installation. These include cupping (when the edges of wood become higher than the center), crowning (when the wood’s edges become lower than the center), buckling (when the wood floor pulls away or rises from the subfloor) and cracking. Gaps and splits can also occur between floorboards or on the face of the boards. These are normal if they appear and disappear with seasonal changes according to the National Wood Flooring Association.5 A problem exists when gaps or splits are large or don’t close during the more humid months of summer.

These same problems can happen even long after a wood floor is installed if suitable temperature and humidity levels are not maintained in a home. For the best long-term performance of wood flooring, the National Wood Flooring Association recommends a range of between 30 and 50 percent normal relative humidity and a consistent home temperature of between 60- and 80-degrees Fahrenheit.6

Maintain your home’s temperature

The bottom line is that if you have hardwood floors and you are leaving your home to go on vacation or to be in a warmer climate for the winter season, make sure that the relative humidity and the home temperature are kept within the acceptable range. While it may save some money on energy costs in the short term, the toll that a cold and damp environment or a hot and dry environment, can take on wood flooring can cost you much more than you save in heating and cooling costs.

A hardwood flooring contractor can help answer any of your questions or concerns so that you are maintaining your wood floors and protecting your investment.

Cameron the Sandman has been beautifying homes and businesses with hardwood flooring installation and hardwood flooring services for over 80 years. We manage each project from start to finish and help you choose the best hardwood floor species, stain, and design layout to meet your needs and desires. Call our hardwood flooring specialists today to learn more about our hardwood flooring services!