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Micronized Copper-Treated Wood is Showing Rapid Decay Raising Concerns for Consumer Safety

CHARLOTTE, N.C., Feb. 9 /PRNewswire/ — Findings on 4×4 posts at residential locations reveal dramatic evidence that wood treated with micronized copper preservative(MCQ(TM)) is decaying more rapidly than anticipated. These decay findings raise serious concerns about the structural integrity and safety of outdoor structures, such as decks and fencing, built with micronized copper preservatives within the last three years.

“We are very concerned about the safety of possibly millions of consumers whose decks and other structures were built with micronized copper-treated wood because the wood may be subject to early failure and possible collapse,” said Steve Ainscough, president and CEO of Viance, a leading provider of wood preservation technologies that refuses to offer micronized copper preservatives due to ongoing concerns about the technology.

Residential Findings in Southeastern U.S. Show Evidence of Significant Decay

Today’s announcement is based on Viance’s in-service findings of decay on 4×4 posts located in multiple residential locations near Atlanta, Georgia and Baton Rouge, Louisiana. Timber Products Inspection (TP), a leading independent and accredited wood products inspection and testing organization in the United States, supervised the identification, extraction and testing of the decaying posts at these locations.

TP’s reports describe numerous posts receiving a rating of “less than sound” on the American Wood Protection Association (AWPA) rating scale. The decaying posts from these multiple subdivisions were rated at “9.5,” “9″ and “8″ on the AWPA’s scale of 1 to 10. One post removed from the Georgia location was rated a “7,” which the AWPA defines as having moderate to severe attack with 10 to 30% of the cross sectional area subject to decay. A decay rating of 7 or below is considered unserviceable by the building industry. TP verified that the average preservative penetration and retentions for the samples examined met the current retention requirements outlined in the International Code Council Evaluation Service (ICC-ES) requirements for MCQ products. The TP report is available in it’s entirety at Viance’s website; www.Treatedwood.com. Furthermore, TP’s reports indicate that the decay is present in the outside zones of the posts below the ground line, to a depth of nearly one inch on some posts.

According to Lee Gjovik, a widely published independent wood scientist, “Any decay on a post that’s only been in service for less than two years represents a significant amount of unexpected decay. Decay ratings of 9.0 or 9.5 should not occur until after many years of service.”

“Another cause for concern,” explains Ainscough, “is that the decay we’re seeing is below the line of sight where consumers may not be able to see or properly inspect the posts. A post’s strength comes primarily from the outer surface of the post, and it is also in this area that the preservatives are present and must prevent decay. The hidden or buried portion of a post must have preservatives that work and prevent decay or the post and structures will fail.”

These recent decay findings corroborate the results of Viance’s ongoing field tests, which were presented to the lumber and building products industries in the spring of 2008 and can be downloaded in their entirety at www.treatedwood.com.

An Overview Of Today’s Technologies

Micronized copper-treated wood products were first introduced to the marketplace in 2006. The manufacturers of micronized copper preservatives, Osmose(R), Arch(R) Wood Protection and PhibroWood(R), have not submitted any of these products to the AWPA for review or standardization. Micronized copper wood preservatives are sold to U.S. builders and consumers through more than 5,000 lumberyards and some leading national home center chains.

Viance remains committed to providing its customers with high quality, industry standardized preservatives, such as Preserve(R) ACQ(R) and Ecolife(R) Stabilized, Weather-Resistant Wood, and ongoing information, testing and investigations regarding the performance of micronized copper-treated products.

Viance LLC provides an extensive range of advanced wood treatment technologies and services to the global wood treatment industry. With an expertise in wood biocides and wood protection chemicals, Viance provides high-level product support to its customers to provide innovative, advanced solutions that improve the performance and durability of wood and wood products. Viance is a joint venture between Rohm and Haas Company and Chemical Specialties, Inc., a wholly owned subsidiary of Rockwood Holdings, Inc. For more information about wood treatment technology and Viance products, visit www.treatedwood.com.

SOURCE Viance LLC

Lumber Talk’s Commentary
CCA was a great chemical. It would be nice if its removal from residential use because of its scary-sounding ingredient arsenate could be substantiated with proof that it was actually harmful (not to wish harm to anyone). It would make the idea that we now use inferior products like MCQ a little easier to swallow.

Osmose’s Rebuttal
Please see Osmose’s MCQ rebuttal which they sent almost immediately after this posting.

Here are some options for those of you perplexed by the question of how to preserve wood posts. Whether you are trying to build a long-lasting fence or other structure or trying to extend the life of existing wood posts you have options. Without exceptions, the options are far easier before installation.

Pressure Treated Wood Posts
No additional work required – just buy wood posts treated for ground contact (usually .40pcf). Depending on the area where you are installing your pressure treated wood posts, they should last between 10 and 30 years (maybe more). 10 years if the area is pretty wet and/or has a bad termite problem and 30 years if the area is pretty dry.

Poly Coated Treated Wood Posts
poly coated wood posts from American Pole and TimberI only know of one place that offers poly coated wood posts – American Pole and Timber based in Houston, TX. The coating is a UV-resistant “poly urea” coating (look and feels like heavy vinyl) and is obviously tough as hell and will not come off of the wood. They guarantee treated poly coated posts will last 50 years. Pretty impressive. The product has only been around for about 10 years but I would put money on 50 years for treated wood coated with a thick UV-resistant vinyl. They supply any quantity but if you are outside of Texas or Louisiana, you might need to buy quite a few to justify the freight expense. You only need to have the post coated from about 6 inches above the ground line to the bottom of the post.

Plastic Coated Wood Posts
Similar to poly coated wood but I wouldn’t put my money on it. Buy treated posts and spray the bottom of the post up to about 6 inches above the ground line with spray-on plastic in a can. You can get a can of spray-on plastic for about $5 at the major big-box hardware stores. One can should easily cover the bottom 3 feet of about 10 posts. It’s cheaper than the vinyl option and should add 10 years onto any posts life.

Sealants or Stains
If you are going to seal or stain pressure treated wood, make sure it is dry first since sealing in the moisture left from the treating process will only make your posts rot faster. Sealing untreated posts will add a few years to their lives but, seriously, just get treated posts – unless you just LIKE replacing fences.

Paint
Paint is for color – not protection. Yes, it protects a little but, again, if you are going to use paint to preserve untreated wood posts just go ahead and admit that you like replacing fence posts. Want color? Paint away. Want preservation? Use treated posts.

The BEST WAY to Preserve Wood Posts
In my opinion, the absolute BEST way to preserve wood posts is with pressure treatment – whichever treatment chemical you choose – and a coating of some kind. The longest lasting wood posts will be pressure treated and coated with the vinyl coating. The most bang for your buck will probably be to use pressure treated posts and spray-on plastic.

Now you know how to preserve wood posts and which methods will work best for you. If you choose paint, don’t call me because I hate replacing posts. I will gladly lay in my hammock – supported by my vinyl coated treated posts – while you install your second set of painted posts, though. :)