Hardwood Floors August/September 2019

By Brian Beakler

NWFA Installation Guidelines require that the average wood subfloor MC is no more than 4 percent from the average MC of strip flooring, or 2 percent for plank flooring, at the time of installation. The moisture content of the wood flooring and the subfloor (if wood based) is typically determined by a handheld resistance-type meter (prong meter) or capacitance-type meter (pinless meter). It is hopeful that you have at least one type, or both types, of these meters at your disposal. If these steps are followed, a successful installation should result. In the situation where the wood flooring is especially high inMC, extra time may need to be added to the acclimation period. Keep inmind, changing theMC in the wood will also change the shape of the wood.This will affect the installation process andmust be taken into account during scheduling. To help expedite the process, there are several things that you can do to help reduce theMC of the flooring. It is highly recommended that all of the material be removed from the boxes (or other packaging) and placed on stickers. Stickers can be anything from scrap pieces of flooring to thick strips of cardboard.The goal is to create 1/2”-plus gaps between the boards as they are acclimating. Typically, these stickers are laid out on the subfloor perpendicular to the length of the flooring at 24” intervals to provide adequate support. Once properly oriented to your available floor space, stack the first layer of flooring across the stickers. Lay the second layer of stickers on top of the first layer of flooring and repeat this pattern. Take caution not to stack too many layers of flooring, as the weight may leave an indent on the bottom layers depending on the hardness of your stickers and the hardness of the flooring you are acclimating (obviously less dense woods like walnut and cherry will indent easier than an oak or hickory). Be sure to align the stickers vertically as you stack your layers of flooring. Alignment of stickers will evenly support the flooring during acclimation. Also, the more time you have to condition, the closer the wood MC will be to both the environment and the subfloor on which it will be installed. There are other effective methods of acclimation as well, but the key is to ensure that the wood has ample exposure time to the environment. The acclimation process is often overlooked or not done properly – typically due to time constraints on the jobsite. By following the simple steps outlined in this article, you can greatly reduce the concern of a customer coming back to you shortly after installation complaining about a gapped, cupped, or noisy installation. g Brian Beakler is Principal at Beakler Consulting Services, LLC (www. beaklerconsulting.com). He can be reached at 717.449.6898 or brian@ beaklerconsulting.com.

the magazine of the national wood flooring association

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