The final touch to a beautifully finished hardwood color is the “surface finish” (colorless poly-urethane wear coats applied in multiple layers on top of either stained or natural hardwood surfaces). These coats provide protection from spills, dirt, normal foot traffic, and minor abrasive wear.

How Many Coats?

Typically in new home construction only two coats of surface finish are specified by the builder due to cost and time considerations. However, many builders are now specifying three finish coats as standard in order to deliver a more satisfactory appearing floor to their homebuyers.

While two full coats of finish will provide a good wear surface, the mechanical screening process required between coat applications, which must be aggressive enough to remove construction contamination from the hardwood surface, consequently may also remove too much of the previous finish coat. Therefore, specifying three finish coats compensates for this problem and produces a final floor appearance which better meets buyer expectations.

Over time, the surface finish will wear away, especially in traffic paths and other high activity areas, and must be re-applied. This process is known as “re-coating” and is a normal hardwood flooring maintenance procedure required every 3 to 6 years depending on the floor wear and tear exposure. Re-coating is relatively inexpensive and can usually be completed within a day by a qualified professional.

Types of Finish Coats

Finish coats are generally available in a variety of luster levels; gloss, semi-gloss, satin and matte. The last finish coat applied to the floor determines the resultant luster level.

Satin and matte finishes are the most popular and preferred luster levels. Having a soft sheen, these low-luster floor finishes reflect less light which help hide scratches, spills and natural surface imperfections better than a glossy surface.

Semi-gloss finishes are the second best option, but high-gloss finishes should be avoided in all cases.

Surface finishes are typically blends of synthetic resins, plasticizers, and other film-forming ingredients, which are suspended in a liquid carrier that is either solvent or water based. Most finishes depend on evaporation of this carrier for curing which can be greatly affected by job site temperature and humidity.

When fully cured, all provide a clear, durable, moisture-resistant finish.

Typical categories of surface finishes are:

Oil Modified Polyurethane
is the most common finish, and the type used by GEORGIA FLOORS. It is easiest to apply, and provides reliable, consistent results under a wide range of job site conditions. This type of finish tends to amber slightly as it ages producing the mellow, traditional hardwood floor look preferred by many homeowners.

Water-Borne Urethane finishes
are best known for providing a clear, non-yellowing finish with a more contemporary appearance. These finishes dry faster and often permit two coats to be applied in the same day. However, water-borne finishes raise the wood grain more than oil-based finishes thus requiring more coats to ensure a smooth final finish. Having higher labor and material costs, they are more expensive, and also less likely to produce consistent results in an uncontrolled environment.

Moisture Cure Urethane finishes
are harder and more moisture resistant than other surface finishes, but relative humidity on the job site is critical to the curing process. This type of finish cures by absorbing minute quantities of moisture from the air, so either too much or too little humidity causes moisture-cured finishes to dry prematurely or not at all. These finishes are extremely difficult to apply, and are only available in gloss luster.

“Swedish Finishes”
are acid-cured urethanes, which are hard, non-yellowing, and fast drying. Type of undercoat, working time, number of coats, and other factors are all critical for acceptable results making trouble-free application difficult. Swedish finishes are not recommended for production home building.

Care
Modern suface finishes for hardwood floors are easy to keep clean. Regular dusting and vacuuming is recommended to remove dirt, grit, and loose particles. Wet or damp mopping is never recommended since repeated contact with water will eventually ruin the finish, discolor the wood, and cause cracks to appear. Stubborn substances should be removed with a recommended hardwood cleaner such as Bona Swedish Formula