Acclimating Hardwood Flooring Hardwood Flooring Guide

Acclimating Hardwood Flooring  Hardwood Flooring Guide

Acclimating Hardwood Flooring

When trees are cut, the logs can contain anywhere from 60-90 % moisture (water) in them. During the Manufacturing process of cutting the logs into boards the Manufacturers have to remove this water by Kiln drying the boards down to 6-12% which equals the Normal 40-55% relative humidity levels found in healthy homes.

All wood including wood flooring whether its a solid hardwood floor or an engineered hardwood floor still has the ability before and after its been installed to absorb and/or release ambient moisture within the environment that the wood flooring is placed.  If hardwood flooring is installed without acclimating it first, in a home environment that has a higher moisture content than what the wood flooring was kiln dried at during the manufacturing process then the wood will adsorb this excess moisture and expand slightly in size. This expansion if extreme, can cause  the boards to swell and expand tight to the walls or baseboard causing cupping and/or buckling of the wood flooring.  Ever had a door stick in the higher humidity levels of the spring and summer months? That same door will open easily during the drier fall and winter months.

If the hardwood flooring is installed without acclimating the wood flooring first, in a drier environment where there is less moisture than 6-12% the wood flooring will in time contact in size slightly, possibly showing gaping between the boards.

Damage to the flooring if any depends on the amount of moisture gain or loss it has experienced. Some expansion and contraction is normal and you might see some cupping and some gaping during seasonal change.  Hardwood Flooring that shows minor cupping or gaping can return normal again during seasonal change.

Acclimating Hardwood Flooring  Hardwood Flooring Guide

Acclimating your new Hardwood Flooring is no guarantee that your flooring will not expand or contact later but it helps balance the scale with regards to how much it will change later.  To help balance the equilibrium it is critical to allow newly purchased hardwood flooring to acclimate to its new environment for anywhere from 1-2 weeks or longer prior to it being installed so that the wood flooring can expand or contract in size to its new environment before its installed.   During the installation it is also critical to leave a space of between 3/8 -3/4 of an inch at all walls or fixed objects so that if there are extreme swings in the normal relative humidity in your region of the country the flooring can expand and/or contract normally.

How do I know what the relative humidity levels are in my home?

There are small inexpensive digital hygrometers found in most any hardware stores that will display the relative humidity levels within your home.  To try and maintain some stability within your hardwood flooring it is recommended that during the higher humidity levels of spring and summer to run air conditioning or de-humidifier normally to remove any excess humidity. During the drier fall and winter heating season its advisable to run a humidifier to add moisture to the air.  Using a digital hygrometer will display where your relative humidity levels are within your home so that you can use the methods above to help control your enviroment.  Your ideal relative humidity target to maintain is between 40-55 % for solid hardwood flooring and 30-60% for engineered flooring.  Any prolonged higher or lower relative humidity levels can cause more expansion or contraction within the hardwood flooring.


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