Acclimation of Hardwood Flooring Information
When discussing delivery and installation dates with clients, they are almost always under the impression that the wood flooring must sit in their home before installation. We’ve all heard someone in the flooring industry say the wood flooring must sit in the home to acclimate for a period of time before installation. There are all different answers from 5 days to 2 weeks or more. This is an old myth from back before wood flooring was properly kiln dried. The wood flooring needed to sit in the home to actually dry out. Wood flooring is kiln dried between 6- 9% moisture content which is the optimum moisture level for a home with normal living conditions.
In most cases, having the wood flooring sit on site before installation will cause far more harm than good. Take for instance, a new home. The wood flooring will be the driest product in the home and will absorb the surrounding moisture like a sponge. New homes have thousands of gallons of moisture trapped inside creating a very humid environment.
For a real understanding of where this moisture is, watch our YouTube video "Wet Houses".
If wood flooring sits on a new home construction site with a relative humidity of 70%, it can easily start cupping inside the boxes within 48 hours. If the wood flooring is in the home while it is being painted, or drywalled, the cupping within the boxes can happen even faster. Drywall mudding and painting can account for over 200 gallons of moisture in a new home. It is all airborne humidity and can create an environment with a humidity level over 90%. Hardwood Flooring cannot sit on site while wet trades are working. Also, since wood flooring is a natural product and each piece is different, the boards will not all shrink and expand the same way. Having a board wider on one end or having each board a different width will make for a difficult installation.
For more information on Width Variations, check out our YouTube video: Click Here
The same is true in the humid summer months. If the wood absorbs moisture on site before it is installed, it will shrink excessively when the home is dry or reaches normal living conditions.
Hardwood Flooring in the Northeast, as an Example
In the Northeast, we have a very unique climate. It is hot and humid in the summer and cold and dry in the winter. Acclimating your flooring too much to either of these seasons can cause permanent damage to your hardwood flooring. If your wood flooring sits in your home too long in the winter and dries out, it will expand and permanently cup in the summer or when the home reaches normal living conditions. This is why it is typically best to install your hardwood flooring right away. Our warehouse is climate controlled to a relative humidity of 40% which is the optimum humidity level for your hardwood flooring. The moisture content of your hardwood flooring will be between 6-9% which corresponds to a relative humidity level between 30-50%. You do not want the relative humidity in your house to go outside this range, not only for the health of your flooring but for your own health.
Of course, there are situations where wood flooring will need to acclimate. If we are delivering our wood flooring to a very dry region like Alberta or Arizona, we will want the wood to acclimate. The normal living conditions in these areas are on the drier end of our recommended humidity range so the wood flooring will need to dry out before installation. If the wood flooring is installed right away, when it eventually dries out, there will be gaps in the flooring. If the wood flooring is to be installed in higher humidity coastal regions, the wood will need to absorb moisture before installation. If the wood is installed too dry, when it picks up moisture from the higher humidity environment it will expand and could cause permanent cupping. The goal is to acclimate the wood to whatever the normal living conditions are and ensure the wood flooring moisture content is within 2% of the subfloor moisture content.
Every situation is unique, and may or may not require acclimation. If someone at a flooring store tells you how long you should acclimate your flooring for without knowing your situation, they have a lot to learn when it comes to the important relationship between wood flooring and moisture. If you have a cottage that is not heated in the winter; a crawl space; a structure on piers; or any situation that may not be considered normal, please contact us at firstname.lastname@example.org for more detailed information on acclimation.