Hardwood Acclimation

Now that the poll is over, I will attempt to answer the question of how long does a solid wood floor need to acclimate. Before I give the answer to the question, I would like to cite an example. Just the other day I went on a job-site inspection, to inspect a solid hardwood floor that had cupped. The contractor was adamant that this was our (my company's) problem. During the initial phone call, the contractor insisted that we pay for and resolve this issue. The flooring contractor stated that all necessary measures were taken before hand to ensure a proper installation. Upon arriving at the job-site, I found a serious moisture problem. Problem #1. There was no vapor barrier under the house and all the ground moisture was gravitating towards the subfloor. Problem #2. The Contractor never bothered to check the subfloor to see if moisture was present. Moisture checks are to be documented (in case one has to go to court). Instead the contractor convinced the home owner to spray a closed cell foam up underneath the house, which sealed the moisture into the subfloor and cost the home-owner 2000 dollars. A plastic vapor barrier would have been much cheaper. Both the home owner and the flooring contractor stated that the wood had acclimated for approximately 2 weeks prior to installation. So the answer to the question is, there is no magic time-frame in which a solid hardwood floor must acclimate prior to installation. Instead the proper method is to check the sub-floor with a moisture meter, as well as check the hardwood flooring itself. The general rule of thumb is to compare the difference between the two. Once the wood and the sub-floor has reached its equilibrium point, installation can begin. Generally speaking, a 3 1/4 solid oak floor should be within four percentage points from the sub-floor. For example, If the moisture in the wood is reading eight percent, then the sub-floor needs to at or below 12 percent. In the scenario mentioned above the subfloor was reading 28 percent and the wood was reading seven percent. That is a difference of 21 percentage points. This floor should have never been installed.
The moral of the story, once again, be careful who you let into your home. This home owner spent 15,000 dollars to have a new hardwood floor installed and 2000 dollars for the spray foam, bringing the total to 17,000 dollars. These types of situations can be very costly, both financially and emotionally.
Should you have any further questions, don't hesitate to shoot me an email at cooperjm68@yahoo.com
Thanks,
The Floor Man