By: Greg Howard and Diego Ignacio Rivas
Although hardwood flooring dates back as far as the 1600s Baroque period, it wasn’t until the late 19th-century Victorian period that the first “finished” hardwood floors began to appear. These finished hardwood floors initially were used in public kitchens and bathrooms, as they were considered easier to clean and “healthier” than unfinished planks that were in widespread use at the time.
The early Victorian finishes, blends of natural ingredients such as shellac and wax, were applied to give a shiny “new look.” These finishes typically were applied after the wooden planks were installed.
Prefinished hardwood floors, like many other modern products, were initially a byproduct of World War II military production. Lumber mills in the United States were making boats for the Navy from oak plywood and were looking for an outlet for their scraps. The scraps were cut into either 9” x 9” or 12” x 12” blocks and finished with a protective wax coating. These blocks were installed in houses, and the first factory-finished, engineered wood flooring was born.
After World War II, more companies began manufacturing prefinished floors. Polyurethane appeared in the market for the first time in the late 1950s. With that, the prefinished flooring market started a period of popularity and technological advancement that continues today.
The 1960s brought a new generation of tough, synthetic resins, and the first wave of exceptionally strong polyurethane varnishes and finishes. Finishing lines at that time generally required a two-pass system in which the color was added in the first pass, and the topcoat was applied during a second pass. Finishing products were cured with heat using either infrared ovens or steam/hot air combination dryers.
The 1970s saw the rise of factory-finished parquet flooring, the development of oil-based finishes, as well as direct-to-consumer sales. Parquet patterns first developed way back in the 1600s became all the rage in the 1970s. Manufacturers produced factory-finished planks and blocks of parquet that could be installed by professionals or purchased for the first time at retail stores for installation by DIYers. Although waxes remained popular throughout the decade, oil-based products offering both color and the desired glossy finish began to dominate the market.
In the early 1980s, finishes were still being cured with heat. This began to change in the middle of the decade. Heat-cured finishing systems began to be replaced by UV-cured urethanes like Teknos roller coated UV finishes, which are still being used today. These products are cured instantly by UV light, not heat, which decreases the curing/drying time substantially. This had a significant impact on the manufacturing process. Manufacturers now could speed up production time, reduce the amount of space needed to produce the flooring, and apply several coats of finish. The expanding use of UV technology also resulted in more durable surfaces than the old stain and wax systems. During the late 1980s and into the 1990s, regulations were getting tighter regarding solvent-based materials and VOC emissions. The environmental movement was growing stronger, and finish manufacturers were developing technology to bring waterborne products to market to replace their solvent-based counterparts. Consumers began to demand improved durability in the late 1990s, and the first finishes with sealer coats containing aluminum oxide were introduced. These sealer coats offered better wear resistance for consumers and resulted in what became known as the “Taber Wars” among flooring manufacturers. The 2000s saw more emphasis placed on durability, as well as more environmentally friendly products. Low VOC materials became a major driver in the market, and still are driving the finishing industry today. Today, UV-cured products continue to be the dominating technology for finishing factory-applied finishes. One can expect UV technology to continue this market dominance in the foreseeable future due to highly effective finishing processes, low/zero VOC emissions, and outstanding durability. In addition, standard putty for knot filling will be replaced with UV curable putty due to easier application, faster curing times, and superior physical properties. The future of UV finishes will be impacted by two major drivers. The first driver will be aesthetics. Consumers won’t be satisfied with durability if the look and feel of the flooring do not meet their expectations. We can expect the development of UV curable finishes that offer aesthetic properties similar to oils and waxes that offer the technological advantages of today’s UV finishes. The second and most important driver is sustainability. Hardwoods are one of the most sustainable materials in the world, offering a very low environmental impact. Correspondingly, the market demands a finish as sustainable as the substrates they are used on. The use of bio-based and recycled materials will increase. The removal of harmful chemicals will continue. Reductions in energy demand are underway already as LED lights replace the halogen lights in UV curing. Finally, consumers will expect a finish that will look and feel like new for decades without regular maintenance. All of this may seem a bit out of reach, but given that, a majority of the floors 80 years ago were bare wooden planks sitting just inches off the dirt, and given the strides we’ve made since then, it is not so hard to envision after all.