Choosing Wood Finishes

Finish is the coatings that are applied to your wood floors that protect against wear, dirt and moisture while giving the wood an attractive color and sheen. These coatings create the lasting beauty of your floors and generally require minimal care, thanks to today's modern technology. In the end, it is your floor finish that will determine the overall color, luster, durability and appropriate care/maintenance for your hardwood floors, so choosing the right one for you is important. Hardwood floor finishes can be broken down into two basic categories, surface finishes and penetrating finishes.

Surface Finishes

Surface finishes are very popular today because they are durable, water-resistant and require minimal maintenance. Surface finishes are blends of synthetic resins. These finishes most often referred to as urethanes or polyurethanes because that is what remains on the surface of the wood to form the protective coating. Surface finishes are generally available in high-gloss, semi-gloss, satin and matte. There are five basic types of finishes:

Oil-Based Urethane/Oil-Modified Urethane (OMU):

Oil Modified is a solvent-based urethane and the most common surface finish used today. It confers a reddish color on the wood, is low in cost, works well with stains, is easy to apply and is generally used in a 2-4 coat processes. The downside of OMU is that it can take a long time to dry and cure, is one of the softer finish types, and will turn yellow or amberize with age.

Water-Based Urethane/Waterborne:

Water-Based Finishes are urethanes, acrylics and blends of acrylics and urethanes, may be catalyzed and come as either a single or two-component product. They are fast drying, moisture-resistant, durable and as the name implies, the vehicular component is water. Water-based urethane has less odor than oil-based urethane and the lowest V.O.C.'s (Volatile Organic Compound) of the surface finishs. Waterborne urethane dries by water evaporation and is clear. Single component waterbornes are generally lower in cost and durability; they also usually yellow over time. Two component waterbornes are the most chemically engineered and advanced of any finish type and the most durable, second only to moisture cure. They are generally non-yellowing and the most resistant to chemicals, scratches and abrasion when compared to the other common finishes.

Moisture-Cured Urethane/Moisture Cure:

Moisture cure is a solvent-based polyurethane that is more durable and moisture resistant that other surface finishes. Most often used on commercial projects, moisture cure comes in non-yellowing and amberizing types of either a stain or gloss sheen. It is extremely difficult to apply, rather toxic and has a very high V.O.C. (Volatile Organic Compound) number. Very few homes have moisture cure urethane on their wood floors and it's availability is extremly limited due to geographical location and emission/chemical laws in many states and regional areas.

Conversion Varnish/Acid Cure Urethane/Swedish Finish:

Most commonly referred to as Swedish Finish, acid cure is a clear, hard, and fast drying finish. Extremely popular in certain parts of the U.S., Acid Cure adds a reddish color to the wood similar in nature to that of OMU. Swedish finish also has a very strong odor and fumes (similar in regard to moisture cure) and comes with a very high V.O.C. (Volatile Organic Compound). Finally, Acid Cure works well with stains but will amberize or yellow over time and takes longer than other finishes to cure.

Aluminum Oxide:

Generally only available in prefinished floors, aluminum oxide is a very hard finish that is applied in the factory with multiple, thin coats. Containing tiny "chips" of aluminum oxide, these particles are added to the urethane and increase abrasion resistance of the finish. The downside of aluminum oxide finishes is that they generally cannot be recoated; instead requiring a full sanding and refinishing of your hardwood floors. Also they are typically only available in prefinished flooring and do not work well on the jobsite.

Penetrating Finishes

Penetrating finishes penetrate into the pores of the wood and harden to form a protective seal. Going deeper into the wood than surface finishes, they are generally made of linseed oil, tung oil and/or other like manufactured polymers. Susceptible to water spotting, penetrating finishes should not be applied where wetting is frequent. After coated, wax is generally applied and buffed into the floor to give them a low-gloss sheen and for durability. With these finishes, wax needs to be reapplied periodically and only certain cleaners can be used on the floor.