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Safer Residential Wood Preservatives Utilize New Technologies to Ensure Protection from Mold and Termites
Wood Treatment Options: New chemicals to treat and preserve lumber have emerged on the market since the industry began removing chromated copper arsenate from the residential sector.
By Matthew Harrison and Elizabeth Grey Morrison
Date Posted: 9/1/2008
Five years ago industrials experts began removing chromated copper arsenate (CCA) off the residential market after increasing concerns about how carcinogens in the chemical could potentially injure children. Since then a number of new treatments have emerged that are impacting the wood treatment market. This article looks at where the technology has been and where it is headed.
Phase Out of CCA
According to the Environmental Protection Agency (EPA), studies suggest that CCA leaches off treated wood over time. This was particularly a concern for treated wood used in decks and playground equipment used by toddlers.
Furthermore, researchers were concerned that CCA could leach into groundwater and affect the drinking water in low elevation areas like
Dr. Darrel Nicholas, a leading wood treatment researcher and Professor of Forest Products at Mississippi State University, said that alkaline copper quaternary ammonium compound (ACQ) and copper azole (CA) are the two major products currently on the market for residential wood treatment. Borates, or chemical preservatives that use boron as an active ingredients, are used predominately for indoor uses because the borates are water soluble, meaning that they can wash off during prolonged exposure to moisture.
Old Standbys of Wood Treatment Industry Compete for Market Share With Innovation
Arch Chemicals, Viance, and Osmose, represent the “big three” of the wood preservation industry. Dr. Nicholas estimates that these three companies command nearly 90 percent of the total wood treatment market.
Each of these companies sells their chemicals to third-party licensees who then apply the chemical coatings long before they reach residential construction sites or the shelves of your local Home Depot. While Arch Chemicals, Viance, and Osmose all have unique varieties of compounds to protect wood, a lot of the basic active ingredients overlap.
Arch Chemicals, for example, offers three different treatment varieties for residential indoor and outdoor use. Genuine Wolmanized® Residential Outdoor® Wood is treated with copper azole, which acts as a fungicide to prevent the spread of brown-rot fungi and dry-rot fungi.
Wolmanized® L³ Outdoor® Wood (pronounced L-cubed), also offered by Arch Chemicals, provides increased protection against termites and other wood-boring insects in addition to its fungicidal properties. Carbon-based Wolmanized® L³ Outdoor® Wood contains propiconazole, tebuconazole, and imidacloprid (PTI) as active ingredients and is best used in above-ground applications.
For indoor use, Arch Chemicals offers StillBor® Borate-Treated Wood, which provides heightened defense against fungi and insects.
Both StillBor® and Wolmanized® L³ Outdoor® Wood are certified to meet American Wood Protection Association (AWPA), but Genuine Wolmanized® Residential Outdoor® Wood still has yet to earn AWPA certification.
“It’s not a rubber stamp, it just takes time,” said Huck Devenzio, manager of marketing with Arch Chemicals. He added that the main reason prevention certification of Arch Chemical’s dispersed copper azole product is the fact that the company only has a few years of data.
Devenzio mentioned that Arch Chemicals is still pursuing AWPA certification for Genuine Wolmanized® Residential Outdoor® Wood and expect to have it by the summer of 2009. In the meantime, the product has been endorsed by the International Code Council Evaluation Service (ICC-ES) and the Good Housekeeping Seal.
Osmose produces several wood preservative products for residential use; these include Osmose Advance Guard®, NatureWood®, and MicroPro®. By utilizing a borate solution, Osmose Advance Guard® protects against termites and fungal decay, and also has the benefit of reducing ant and cockroach populations that may live in the wall systems.
Advance Guard® is available for use in above ground weather protected structural framing in residential and commercial projects. As with untreated wood, Advance Guard® Borate Pressure Treated Wood may be sawn, drilled, or routed with standard woodworking equipment.
Another product, Osmose’s MicroPro® technology combines the revolutionary elements of pressure treatment and micronized copper quaternary and micronized copper azole to reach optimal performance for outdoor uses in decks, fencing, landscaping, and general construction.
MicroPro® treated wood products also offer better corrosion resistance for code-approved fasteners and hardware. Doug Fenwick, Director of Global Marketing, said the micronized copper is pressure treated into the wood the same way it has been done for over 70 years. The product benefits of MicroPro treated wood include effective protection against fungal decay and termite attack in above ground, ground contact, and fresh water applications, building code compliant, and the treated wood can be used in direct contact with aluminum.
“The MicroPro technology is the first and only wood preservative system to be EPP (Environmentally Preferable Product) certified by Scientific Certification Systems, the same third party accredited organization which audits the FSC lumber program” Fenwick stated.
MicroPro® is an ICC-ES building code compliant product. MicroPro® does not have AWPA standardization.
Fenwick said MicroPro is currently sold by over 4,000 retail
Viance’s primary outdoor wood treatments, Preserve® and Preserve® Plus® use ACQ as the primary chemical component to combat mold and insect infestation. Preserve® Plus® also includes an additional solution to provide addition rain protection.
Timbersaver® PT, also by Viance, is treated with boron-based Disodium Octoborate Tetrahydrate (DOT). Timbersaver® PT is best used for dry interior applications such as wood frames, trusses, floor joists, and sill plates in residential construction. It protects against fungal decay as well as termites and other harmful insects.
Viance’s Preserve® Timbersaver® PT are both AWPA certified, and its newest product, Ecolife™ is currently in the review process. Ecolife™ which already has ICC-ES approval, contains a revolutionary non-metallic stabilizer that protects against weathering without affecting the lifespan of nails and fasteners.
One of the major concerns of ACQ and CA wood preservatives is their tendency to corrode nails, fasteners, and other metallic pieces, said Dr. Nicholas. He added that they tend to leach more copper, too, but not enough to raise health concerns. “CCA was like the Cadillac of preservatives.”
Still, the post-CCA wood preservative industry relies heavily on copper, but Viance is one of the first companies to market a residential outdoor wood preservative without copper. “There’s a lot of research and activity in developing all organic systems,” Dr. Nicholas remarked, but he stops short of fully supporting wood preservatives without copper. “They simply won’t perform quite as well without the copper in them.”
Newcomers Bring Ingenuity,
Among the many wood treatment alternatives available on the market today, Bluwood is a recent addition providing customers with assurance against mold and infestation.
Developed by WoodSmart Solutions headquartered in
“The major focus of our business is that we have independent license treatment facilities around the country that actually apply the product in a controlled factory environment,” Morando said. “We’re supplying the building materials distribution network for professional builders.”
In terms of cost, Bluwood is about 20-25% more expensive than other types of lumber. However, the product is treated with a two-part coating technology which entirely blocks the growth of mold and protects the wood from rot and insects.
The first component of this technology is an Infusion-Film that forms a water-repellant film interlocking with the wood fibers to provide controlled topical and subsurface moisture absorption. The second part of this technology includes DOT Borates, established fungicides and insecticides that provide protection from rot fungi and insect infestation. An environmentally friendly product, Bluwood is listed in the GreenSpec™Directory and meets the criteria for use in Leadership in Energy and Environmental Design (LEED) structures. Morando said that Bluwood structural lumber comes with a lifetime warranty on performance, and even has a transferable warranty to future homeowners within 30 years.
Nisus Company also offers several different products to protect against mold and termites.
Dr. Jeff Lloyd, vice president of research and development, said that while Nisus Company primarily sells to pest control applicators in the
Bora-Care, for example, can be used on structural wood as a termite pre-treatment. Lloyd said the product not only creates a protective barrier against wood destroying pests, but also effectively prevents decay fungi and the growth of mold.
As an additional plus, Bora-Care received the Best of Show award at the 2006 National Green Building Show for its positive impact on the environment.
Gemini Coatings, Inc., a company that primarily manufactures indoor wood treatments, has also come up with an exterior product called Total Wood Preservative (TWP). Widely used on decks and furniture, TWP has also been used on log homes and even an outdoor fishing museum.
Creative Director Doug Lacina said TWP protects against rot, water absorption, ultra violet light and mildew. The average life protection of TWP ranges between three to five years before another coat should be applied. The cost is approximately $20 to $25 for one gallon, and $112 to $115 for five gallons.
If green is a priority, then perhaps a product from Green Envirotek of California would be appropriate. This company has developed a wood treatment option with a competitive edge: fire protection. Wood Gard Mih, a salt-based formula, is a flame retardant that has the additional benefit of protection from termites.
Darrell Smith, president and CEO, said the product can be used on structural timber. The product has a ten year guarantee, but has the potential to last much longer.
Smith said the product does not protect against UV rays, so if it is used on exterior wood, the best option would be to apply a top coat. However, if used indoors, the product can stand alone. “As long as it is not exposed to UV, it should last indefinitely,” Smith said.
Wood Gard Mih can also be used in LEED certified applications, and is applied by a spray. The product costs about $2 per square foot, but don’t calculate prices too quickly; Smith said Green Envirotek works with insurance and mortgage companies to provide benefits that can help offset the costs of the product.
The wide range of products on the market illustrate how EPA’ regulation of CCA in residential applications has spurred innovation across the wood preservative industry. By reaching an agreement with the EPA before an all-out ban, the wood preservative industry demonstrated its commitment to well-being of its customer without sacrificing profit.