What it is: Long cracks in the veneer that run along the length of the board in engineered flooring. It typically occurs when flooring is manufactured at a higher MC and installed where it will be exposed to much lower relative humidity (RH). As the veneer dries, it is held in place by the glue and fractures as it shrinks.
Different manufacturing problems, such as the face veneer and core veneer being manufactured at different MC levels or having different dimensional change coefficients, can make this issue even worse. Rotary peeled veneer will face-check more easily than a sliced veneer. A sawn face, if very thick (3.5 to 4 mm), can also tend to face-check if not well-controlled by humidity levels being maintained in the home.
Common species: Any (top photo is engineered tiete chestnut, photo on right is engineered Brazilian cherry)
What to do about it: Again, many exotic products are manufactured abroad with a much higher MC than they will have once they’re installed on the job site. Be sure you buy from a reputable manufacturer, and be especially wary if the installed floor will experience low RH either year-round or seasonally.
What it is: Separations of the wood that normally occur across or through the annual rings. Cause: • Loss of moisture due to drying processes during manufacturing, or environmental conditions during storage or after installation. Cure: Board replacement, with a recoat if necessary.
Checking consist of fine hairline cracks running along the grain on the surface of the wood flooring. Checking most commonly becomes noticeable in late winter or early spring after months of low relative humidity. Low humidity, a site related condition is the primary cause of checking. It is possible for some checking to be related to manufacturing issues. Both solid flooring and engineered wood (plywood core) are subject to checking.