I recently spoke with George Palmer of Premiere Finishing and Coating in Reidsville, NC, about the green nature of factory finishing. I was prompted to contact George after I saw this in one of Premiere's newsletters:
Myth: Water base finishing on wood is the best method to use for low VOC (Volatile Organic Chemical) emissions.
Reality: Using water base coatings would greatly increase the VOCs of our finish.
That definitely made me want to learn more. George was quick to answer, telling me that one of the most frequent questions he is asked is: "Can you use water base coatings on your line to get low VOCs?" And that he likes to answer it with another question, "Why would I want to use water base and increase my VOCs by more than 100 fold?"
George went on to explain that a water based coating can be over 20% VOC by weight while the ultra violet (UV) coatings used by most prefinished flooring manufacturers are formulated with virtually zero VOCs. Almost all water base finishes have between one and two pounds per gallon of "co-solvent," usually a type of alcohol that will mix with water. It is used to speed drying (you don't want to wait months for that finish to cure, do you?) and to enable the use of materials that will not dissolve in straight water. All of that solvent enters the atmosphere as VOCs.
On the other hand, most Ultra Violet (UV) coatings are made from liquids that turn directly into solids through chemical reactions when they are exposed to UV light. That means that there is no solvent or oil left in them to evaporate. Once applied to flooring on the line, they are immediately exposed to a UV light that converts them from a liquid to a solid film in about three seconds. The reality, George insists, and as I've always felt, is that if you are looking for a green finish, a UV cured product is far superior to water base.
George provided me with some basic facts about their production and the green nature of UV finishes:
*The UV coatings have basically no VOCs. "I don't think they, or any product for that matter, can be listed as absolute zero VO's because testing of the final finished floor may turn up small trace amounts of some VOC of some type. However, testing cannot determine the origin of the VOC-it might be from the coating, as unlikely as that would be, or they might be from a glue if the product was an engineered floor, or even from the wood itself-as you've referenced before in your blog, the smell of fresh Pine is actually a VOC."
*The production process is also very green. "UV coatings are applied by precision roll coaters and all unused material on each roll is re-circulated into the unit's reservoir so we have virtually 100% transfer efficiency. No material is wasted and/or put into land-fills."
*Flat line, finished flooring is sanded prior to finishing by a sander that controls sanding dust with a powerful, vacuum system. No sanding dust enters the outside atmosphere or the home. Dust collected at a job site is usually just wasted fiber, but dust collected at a factory can often be burned for power or used by HDF or other facilities, further maximizing the use of our valuable resources. On the other hand, site finished flooring must sanded in the home prior to the application of finish.
*UV coatings accommodate Aluminum-oxide which provides abrasion resistance. "Aluminum oxide particles cause difficult application, suspension and curing problems that have been mastered for flat line finishing. However, to my knowledge, site applied finishes are still grappling with them. Al2O3 finishes can increase the lifetime use of the floor which is a green feature, plus decrease maintenance time and costs which I would also consider to be a green point. This is also a plus for marketing, because flat line pre-finishing is commonly warranted for anywhere from 10 to 50 years."
So clearly prefinished flooring is extremely green. It's also the subject I personally know a bit more about than how to do site finishing, so I welcome input from site finishers about what they can do to keep a job site green. I did post a few tips last year in this blog, but I'm sure there are plenty more ideas out there. Please share your best green features.