Micronizing Treated Lumber Pros & Cons

Corrosion

• Prior to 2004 treated lumber meant "CCA": a combination of copper, chromium and arsenic. Due to health and environmental concerns about exposure to arsenic, CCA was phased out and replaced with alkaline copper quaternary --- called "ACQ" --- and copper azole --- called "CA." Both deleted arsenic but relied on copper to provide the same protection. One problem with these two processes as compared with CCA was the corrosive effect on metals. Only special screws, nails and fasteners could be used with ACQ or CA lumber. Micronized lumber solves this problem. It does not require the solvent so it is less corrosive. Use aluminum and standardized galvanized hardware with micronized lumber.

Color

• CCA treated lumber along with its successors, ACQ and CA, give the product a green color. This distinctive color identifies treated lumber but it also affects the appearance of decks, fences and other uses of the product. The new micronizing procedure produces a lighter color wood. It is more suitable for lighter paint and stain colors. It presents a closer appearance to natural untreated lumber.

Cost

• Lower costs have always been an advantage of treated lumber over untreated lumber when factoring in the long life of treated lumber. Some of the cost savings disappeared as ACQ and CA treated lumber requiring more expensive fasteners, nails and screws. Micronized lumber reduces those costs due to its utilization of the less expensive hardware.

Decay

• According to Deck Magazine, micronized lumber's ability to resist decay over time, particularly with lumber that contacts the ground have been questioned by a competitor that sells a preservative that does not use metals. The manufacturers of micronized lumber dispute these allegations. Because the lumber must be in the ground for a period of years before decay would take place, as of this article's publication, the debate continues.