What’s New in Treated Wood?

What’s new in treated wood? First a brief review of developments of which you might be aware. Chromated copper arsenate-treated wood was largely removed from the market in 2004. CCA was replaced by ammoniacal copper quaternary and copper azole, both of which cost more than CCA. But like CCA, the active ingredient in these newer products is copper, and it is in such concentrations that it can corrode steel fasteners.

An old standby, borate is a wood treatment that was long recognized as a low-toxicity wood preservative, and it has achieved renewed popularity as a termiticide additive for companies that have chemically reduced borate’s water solubility, a real issue in ground contact situations (Bora-Care from Nisus and Tim-Bor are examples).

But what’s really news is the accomplishments companies have achieved disguising wood as a food source for mold and insects by chemically altering its nature through a nontoxic process. This is where the action will be over the next decade.

Here are a few examples.

Though it has had its struggles on the legal and production fronts, Timber Treatment Technologies created and marketed TimberSil, a wood product that holds enormous promise. TimberSil uses sodium silicate and heat to create layers of microscopic glass within the wood, thereby preserving it. Nonetheless, with such a promising technology and a huge U.S. market — more than 15 billion board ft. each year — TimberSil fell into legal problems in 2006 and lost its distribution deal with Huttig. But now TimberSil is staging a comeback and is taking order after regrouping. This is worth a good long look.

Another interesting new wood product — this one just for decking — is PureWood. It’s real wood that is treated with heat and steam so the wood cannot support rot and mold (heat thermally modifies wood sugars). No chemicals or metals are used in the process, and PureWood is 100 percent real wood, with a 25-year warranty against rot and decay.

Yet another increasingly popular treated-wood product is Bluwood. Bluwood treats lumber — any lumber, from sticks and plywood to engineered beams — before it gets to the jobsite, coating it with a proprietary blue-colored two-part film-and-preservative technology. The product has received great performance reviews and its distinct color has helped with its branding.