The hardwood flooring industry has always been steadfast in its assertion that water and wood don't mix. The fear of exposure to water, whether minimal or excessive, continues to be our industry's black cloud - even on the sunniest days of installation.
There are favorable and not-so-favorable characteristics inherent in all types of floor coverings. Every known resource within our industry is virtually powerless to protect any wood flooring product from the expansion caused by exposure to excessive moisture. Fortunately, in most cases, all the installation requires is a little time to dry and the product will return to the dimensions it had at the time of installation.
It is also vitally important to remember the role that Mother Nature played in developing our wood resources. Those resources - making use of sunlight, water and nutrients in the soil - followed nature's dictum to grow and expand.
Any hardwood floor installation that is subjected to moisture responds to the "training" taught to them by Mother Nature. Without question, they learned their lesson well because, in the presence of sufficient moisture, the wood flooring product will again grow and expand - at least temporarily.
Like many natural products, wood flooring has the capacity to deliver a lifetime of service - provided that both the installer and end user are aware of the need for proper care, maintenance and, most important, a compatible environment. If adverse conditions, such as the presence of moisture and/or high relative humidity, are present before, during or after the installation is completed, behavioral problems in the installation inevitably follow.
We, as an industry, must portray and convey the need for balance in each and every hardwood flooring installation. Today's manufacturers are constantly updating their dry kilns to extract excess moisture from raw lumber, which traditionally is also allowed to air dry in the yard for three to four months, before the hardwood floor manufacturing process commences.
Under such circumstances, it's highly unlikely you will ever encounter a hardwood floor product that could be considered "green." However, moisture can still have a negative effect if the product isn't handled properly after it has been manufactured and packaged. Both the distributor and contractor are responsible for providing the proper shelter and required acclimation procedures, and making sure that job site conditions are suitable for the installation to proceed.
Let's go one step further. A lack of moisture and low relative humidity can create a totally opposite problem for a hardwood installation. Old Man Winter is nearly upon us. Hardwood flooring products are manufactured with a moisture content level that ranges between 6% and 9%. Acclimation is just as important in dry-heated conditions as it is under consistently damp and humid conditions.
Probably the best way to monitor the moisture content of the product and relative humidity is through the use of meters specifically designed for this purpose. If you purchase one of these units, I'll wager that you'll probably come to view it as one of your wisest investments in the tools of your trade.
Much like a physician's stethoscope, the moisture meter affords the contractor the ability to explore what's going on inside the hardwood flooring material. (And as we all know, a doctor wouldn't think of leaving home without a stethoscope. Maybe that's why doctors always store them around their necks.) The least the wood floor professional can do is stow one of these meters in the truck and bring it into the client's house for a job site evaluation on the first visit, rather than breaking it out on a subsequent trip precipitated by a problem with the installation.
Hardwood flooring's behavior is actually more predictable than the local weather. And, unlike the weather, you can definitely control the behavior of a hardwood floor. Outdoor conditions during the winter season are less destructive to the hardwood than the dry-heated indoor conditions imposed by the homeowner.
In reality, hardwood floors are very similar to the consumers who utilize them. Consumers in dry-heated homes who complain about cracks in their wood floor installations likely would also notice dryness in their noses and throats, especially upon awakening in the morning.
Hardwood floors always react to any major change in environmental conditions. Maintaining a constant and consistent indoor temperature and relative humidity can and will keep your floor from undergoing dimensional changes. Convincing your customer that gaps in her wood floor will disappear, returning the product to its original dimensions, once the intense dry heat has been removed could be more of a challenge than closing the original sale itself.
Dryness in the air depends upon the amount of moisture it contains as percentage of the maximum it's capable of retaining. Heating indoor air decreases the "natural" relative humidity that may be found outdoors at any given time. When the natural relative humidity is modified, the heated indoor air is then capable of maintaining "replacement" moisture from another source, such as a humidifier.
Whether you're working in a tract home or a high six-figure custom residence, seldom will you find a humidifier installed by the homeowner or the original builder. To me, jeopardizing the lifetime investment of hardwood flooring for a mere $300 add-on humidifier makes no sense at all. Today's homebuilders are focused on energy efficiency, a noble trait. Unfortunately, these job site-assembled homes are becoming "Saran wrapped" packages that ultimately exacerbate the acclimation problem.
In any event, consumers should be advised of their responsibilities and expectations before they experience heat- and humidity-related changes in their wood floors. In reality, no corrective measures are called for, because dimensional changes in hardwood flooring should "cycle out" in step with the seasons of the year.
Removing and replacing the installation is no guarantee against a recurrence of such problems. I suggest that any homeowner concerned about this problem install a humidifier and leave the fan on the thermostat in the "on" position. This will allow moist air to circulate throughout the house even when heating is not be required.
Wood or Wood Knot will always be there in the "open trenches" with you. Closing them, however, is up to you.