What it is: The center of the pieces of flooring appears to be
higher than the edges.
While it is theoretically possible that excessive moisture could cause
crowning, it is more likely that the floor cupped and then was sanded
flat before it could dry and flatten on its own. When the floor boards
did dry to a normal condition, their edges had been removed, making them
lower than the center of the board. Gaps are generally formed as the flooring
First, determine if the moisture content is normal and if all of the crowning
from the original cupped condition has occured. After the floor has stabilized,
resand and finish.