Moisture Testing and Hardwood Floors

What many installers and builders often fail to recognize when it comes to hardwood flooring, is the moisture content in the actual subfloor. Without paying attention to it and an imbalance between the subfloor and new hardwood flooring can cause unsightly affects with the most common being cupping. Both wood and concrete subfloors should not be exposed to excessive moisture.

During the building process many subfloors can sit and soak during rainy days. For excessive rains over prolonged periods keeping subfloors free of standing water can prove helpful. Essentially there is no cause for alarm with wet subfloors during this period. However, if the entire building process is rushed and the subfloors do not dry out properly problems will happen.  For best results in new construction, floors can be protected, but the key is allowing enough drying time and have all windows and doors installed prior to hardwood.

Types Of Moisture Testing. Hardwood Flooring

Unlike fifty years ago hardwood flooring comes from different parts of the country or with exotics, the world. In earlier days trees were often used for flooring from surrounding forests. Flooring of the time adjusted to the regions average moisture content. For example, it was not cut down in the hills of Northern Arkansas and shipped to Boston, Mass as much of it is today. It may follow all the necessary drying periods, but who is to know where it will be stored before it comes to your home? Some warehouse on the banks of the Hudson River? River you say, moisture?

Ambient moisture content will vary depending on your climate. In drier climates, content should be lower before the installation and vice versa with areas of higher moisture. Without any attention in testing for moisture your new floors could possibly shrink or expand.

There are several hand held meters used for testing moisture. Some can be purchased online and can prove to be a beneficial tool for other areas of the home during building. Haven't we all seen shrinking wood work or paint jobs that should have been done during better conditions? This all relates to improper moisture conditions.

Some of your better moisture meters can test for all types of building materials, but in this case we'll look at wood meters. Included are calibrations used for different species as meters check for moisture but specific gravity or denseness plays a role in determining the actual content level.

Other Notes

Acclimation of hardwood floors to the jobsite, proper moisture testing and control, before, during, and after the installation plays a very important role in the behavior of your hardwood floor investment. Many hardwood manufacturers suggest keeping the relative humidity of the home in the range of 40-55% after the installation to maintain the floor's original appearance. Not doing so will cause shrinkage, swelling (buckling) or other unpleasant surprises.

It's important to discover what the average moisture content may be in your region to determine what is best suited for your install needs. What may prove successful in Florida for example, may not be for southern California. Other forms of moisture testing are meters that test moisture in concrete subfloors. Additionally, relative humidly can play a significant role before, during, and after the installation. Below are some other tools knowledgeable hardwood installers rely on.

DIY Moisture Testing

For those that do not have access to expensive moisture meters, one simple test can be accomplished on concrete subfloors for less than ten dollars. Obtain some poly film (visqueen) and duct tape from any local big box store or hardware store. Cut a half dozen pieces (more if the layout is larger) into 2' x 2' sections, place them randomly in your installation area, duct taping the perimeter to the concrete slab. Making sure it's sealed completely and adhered to the concrete, allow them to sit for 24-48 hours then remove. If any condensation or color change takes place in the concrete you have moisture issues that need to be addressed before any installation is considered.