You may have heard that it's important to acclimate hardwood flooring before it's installed. If you haven't heard, let me confirm that acclimation is very important.
Acclimation is accomplished by allowing the wood to sit in the room, where it will be installed, for about a week. The wood will adjust - or acclimate - to the humidity and
temperature of the room. Why is that important? If, for example, the humidity in the room is low and the humidity in the room where the wood came from is high or higher, you may have a problem if you install the flooring right away. The moisture level of the wood will adjust to the new surroundings by decreasing. As the moisture level decreases, the wood will "shrink" and gaps between the boards will appear. The opposite can happen as well if the moisture in the new environment is higher than where the wood came from. In this case, rather than shrinking, the wood will expand potentially causing the boards to "buckle" or rise at the seams.
Acclimation does not always accomplish the desired outcome. Here in Colorado Springs, for example, where the air is very dry, a problem with acclimation may happen in spring or summer. If it's been rainy, the humidity levels in the air will be higher than normal meaning that any wood that is acclimated to these conditions will have a higher than normal moisture level. If the wood is then installed at the elevated moisture levels, "gapping" will likely occur when the humidity returns to normal levels or when the humidity drops to even lower levels during the fall and winter months.
So what can be done to acclimate the flooring when humidity is high? A dehumidifier can be placed in the room with the wood "forcing" proper acclimation. To help determine whether the wood has been successfully acclimated, a moisture meter can be used to check the moisture level. In Colorado Springs, Red Oak, for example, should read between 5% - 7%. If the moisture level is higher than this, further acclimation is required.
In order to help stabilize the humidity levels throughout the year, a humidifier should be used during the drier months. Maintaining humidity levels of 30% or more will keep your floor from drying out to the point that gaps appear between the boards. If you still have gaps in your floor after maintaining proper humudity levels for a month or more, it might be time to talk to your hardwood flooring professional. If, however, the gaps are small and don't bother you, doing nothing is not a bad decision. If you clean your floors properly, the amount of water or moisture that ends up in the cracks will be minimal and no cause for alarm.