hardwood flooring acclimation

Expert’s Corner: Acclimating Your Engineered Hardwood

One of the more crucial steps for a successful engineered hardwood flooring installation actually takes place at least three days beforehand. It’s called “acclimation,” and it’s the process that syncs the moisture in engineered hardwood flooring to the humidity level of the environment it will be going into at the time of installation.

Why Acclimate Hardwood Flooring Before Installation?

Hardwood flooring comes from a living organism, which means that it responds to the moisture around it, even while still boxed. When a carton of wood flooring arrives at your door, it has either expanded or contracted based on the humidity levels it has previously been subject to. The goal of acclimation is to strike a balance between the wood’s natural moisture content and that of its environment. If acclimation does not occur, hardwood floors run a very high risk of swelling or shrinking post-installation, resulting in gapping or cupping.

Gapping occurs when hardwood flooring’s moisture level is higher than its environment. Planks will eventually shrink after installation once it adjusts to the lower humidity, resulting in a separation (or gap) between planks’ edges. Cupping occurs when hardwood flooring’s moisture level is lower than its environment, causing planks to swell in the center from the additional humidity and crush together for a bulging look. Both of these occurrences are not only unsightly, they can also result in a “noisy” floor when walked on.

Acclimating the wood prior to installation allows the wood to adjust to the environment’s moisture level so that when installed, it will be the correct size.  This, of course, is contingent on keeping the moisture levels in the environment within the recommended range of 35-55% with a temperature ranging 60-80 degrees Fahrenheit.

acclimating hardwood flooring before installation

Tips for Acclimating Hardwood Floors

When acclimating hardwood floors, it is also important that you check the moisture content of the subfloor if it’s wood.  NWFA Installation Guidelines require that the average wood subfloor moisture content should be no more than 4 percent from the average for strip flooring, or 2 percent for plank flooring, at the time of installation.  Most professional installers will check this, however if the installation is a DIY project you will need a handheld resistance-type meter (prong meter) or capacitance-type meter (pinless meter).

The easiest and most common way to acclimate is to place the cartons in the room you’ll be installing in for a minimum of three days prior (longer is always better). If you have the room, space the cartons out. If not, cartons can be stacked (but staggered) to allow as much air to circulate as possible. You can expedite the process if need be by removing planks from their cartons and placed on scrap pieces of flooring or thick strips of cardboard, leaving 1/2”-plus gap between boards as they are acclimating. It’s that simple.

acclimation hardwood flooring before installation

One Response to “Expert’s Corner: Acclimating Your Engineered Hardwood”

  1. This is great. It is still recommended by manufacturers to acclimate engineered hardwood floors at least 48 hours or until they reach their acceptable moisture content. Do this inside the room where they will be installed. Its plywood core helps mitigate dimensional changes but it does not totally eliminate it. Thank you for sharing.


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