There are few flooring materials that look as warm and as inviting as wood, but some people may be worried about the boards cupping or crowning. Wood floors are quite common in office or business settings, for their durability, appearance and easy care. However, some business owners may be understandably dismayed to see parts of the wood flooring doing something besides sitting flat.
What are Crowning and Cupping?
Whether the wood flooring is solid or engineered wood, it can be subject to crowning and cupping. Diagnosing the issues means visually inspecting the boards and looking for whether the center of the board is higher than the sides (crowning) or the sides of each board are higher than the center (cupping). Both conditions have to do with the moisture content and how the wood responds to that.
Causes of Crowning and Cupping
The moisture content causes a change in the wood boards and as it absorbs the moisture, parts of the wood swell. Moisture can come from leaking water or water vapor from the surrounding air. In other words, water is introduced to the bottom of dry flooring boards.
When the moisture content is higher underneath the board than it is on the face, the crowning and cupping will take place. Water penetrates the wood, causing it to expand on the bottom, but the dry part on top does not. Moisture creates tension differentials between the top and bottom layers of the wood. Cupping and crowning can take place within a few days after installation, or it may take a few weeks or even months to manifest.
Fixing Crowning and Cupping
When the cupping or crowning is slight, a flooring expert simply needs to fix the source of the water (as in a plumbing or appliance leak) and let the flooring dry out, often with the aid of a fan or dehumidifier supplied by a commercial drying service. Special equipment that creates low humidity, air movement and heat can help. In some cases, flooring may be sanded down to flat again if the wood boards do not get that way on their own.
The bottom line is that moisture is the cause for crowning and cupping in wood flooring, and getting rid of the moisture is the proper way to get the wood flooring to stay flat and true. A flooring inspector can assist concerned business owners or home owners about the next step in fixing these issues.