Advanced hardwood flooring considerations: grain
One of the things that makes a hardwood floor so appealing is the grain of the wood. Many types of flooring material have a repetitive pattern, but wood grain presents a natural randomness in which every board may be different. The overall effect on the eye is calming and pleasant – an understated elegance.
There is more to wood grain, however, than just a series of rings. Granted, annual growth rings are the most commonly recognised element in wood grain, but in most hardwood flooring applications, the familiar circular pattern will not be evident. This is because planks intended for hardwood flooring are usually cut parallel to the trunk of the tree, not crosswise through it.
The grain in a plank of wood may exhibit several features including “figure,” which refers to a pattern formed by not only growth rings but also by the knots and other natural variations that may be present in a given section of wood. One of these other natural variations derives from a tree structure referred to as medullary rays. These reach from the core of the trunk out toward the bark and may be extremely thin – only a few cells across in some varieties of tree. In other species, such as oak, medullary rays may actually be several inches across instead.
Many flooring planks exhibit what experts call tangential grain in which the growth rings intersect the plank at an angle – typically of 45 degrees or less.
Regardless of the grain pattern in a hardwood floor, regular maintenance in the form of floorboard sanding will be required on a periodic basis.