Traditional wood floors are increasingly giving way to engineered products due to improved product performance and reduced cost. With some advanced processes you can have an engineered wood floor that truly looks and lasts like solid wood and can be installed where solid wood is impractical. Let's review the limitations of solid wood products and the benefits of our engineered counterparts.
Shrink or Swell: The Properties of Wood
Most wood cells have a long tubular shape, are typically vertical in the main stem of a tree, and have a significantly smaller radius than length. Many of woods' structural properties derive from cellulose molecules in the cell wall that attract and chemically bind water. This 'bound' water in the cell wall equilibrates with the relative humidity of the atmosphere around the wood causing the wood to shrink or swell over some time, usually a seasonal change.
If you compare the rate of expansion or contraction across the face of a board to the length change it is typically 50 to 100 times greater across the face. Wood experiences much less movement along the direction of the cellulose molecules. Wood floor installers allow for movement across a floor by leaving expansion gaps next to walls. Traditionally, the use of solid wood flooring directly over concrete has been avoided because of moisture issues.
Shrinking and swelling in engineered wood products is greatly reduced by gluing layers together with the alternate layers turned ninety degrees. The shrink/swell in cross ply construction is dominated by the low expansion coefficient in the direction of the cellulose molecules, resulting in a reduction of the shrink/swell across the face by a factor ranging from 10 to 20 times - far less than solid wood.
The Facts About Engineered Wood Floors
Engineered wood flooring offers the advantage of using a smaller amount of high quality or rare wood for the face. Some of the lesser quality-engineered flooring contains smaller pieces that are not suitable for use in solid flooring, resulting in a chopped up look. However, a high quality engineered flooring can be produced from full size boards and maintain the same aesthetically pleasing look as a traditional floor. Ask for a product with certified low formaldehyde emissions from the glues and backer.
A wear layer comparable to a solid wood floor can be achieved using a precision 'frame' saw instead of slicing or peeling the faces. A thicker wear layer requires even more attention to the details of the profile. One example is the location of the tongue and groove; setting them too high on a product with a thick wear layer increases the risk that the flooring will not remain flat.
Choose Wisely... Choose Wood
Wood floors are durable and easy to live with. The direct benefit of adding value to the home is a recognized bonus. Modern finishes require little maintenance and can be cleaned without the use of harsh chemicals, furthering woods' value as being environmentally sound or 'green' friendly. The long service life reduces the amount of solid waste. And an important benefit for the homeowner; wood is hypoallergenic, thus avoids problems associated with some other floor coverings.