The Manufacture of Engineered Hardwood
Engineered hardwood, much like plywood, is manufactured of thin sheets of solid wood. The number and thickness vary from one manufacturer to another. Most top layers on engineered hardwood are less than 1/4-inch thick. The grain is run in opposing directions from layer to layer to create a product that reacts to changes in moisture in a more uniform manner than solid wood.
Solid Hardwood Sanding
Traditional floor sanding is a process reserved for only the most severely worn or damaged floors and is generally done only once or twice in a floor's entire life span. A drum sander is used to grind the clear finish and stain layers from the floor to completely resurface the wood, revealing an unscratched, unstained, inner layer. This process can remove as much as 1/4-inch of material and, as such, is incompatible with engineered hardwood construction.
The finish on engineered hardwood flooring is applied during the manufacturing process and effects more than just the surface layer. The stain and finish are typically combined in multiple layers that cannot be fully removed without damage to the flooring itself. While additional coats of clear finish, and some surface stains can be used, changing the color, or complete refinishing are typically impossible.
A process known as screening can be used on some engineered hardwood floors to repair scratches that do not penetrate the stain layer. A floor buffer is used with a specialized screen that essentially “sands” the top layer of the clear finish from the boards. Care must be taken to prevent screening any deeper than the clear finish layer to prevent damage to the floor planks. Once screening is complete, two to three coats of clear finish will need to be applied to reseal the floor and complete the repair.
Engineered Hardwood Maintenance
Typical maintenance procedures for engineered hardwood include sweeping or dust mopping and damp mopping with gentle detergent or a water and vinegar solution to clean surface dirt from the floor. Doing this on a regular basis will minimize the dust that grinds the finish and dulls the shine. Applying a coat of clear wax or finish periodically will help to maintain the finish and may prevent the need for screening.