Pesticide-Treated Lumber

Although Germany has been a leader in the Bau — Biologie and healthy housing movement, it was only two decades ago that the general public there became aware of multiple chemical sensitiv­ity disorder. This awareness followed the experi­ences of thousands of people who were exposed to lumber treated with both the preservative pentachlorophenol and the pesticide lindane. Hundreds of people developed chronic neurologi­cal complaints, chronic fatigue, and an unusually heightened sensitivity to chemicals that were pre­viously tolerated. Lindane has subsequently been banned in Germany as a wood treatment.

dipped in pesticides that are now banned in the US. In some cases, uncontaminated lum­ber can be picked up directly from a local mill, where the sawyer will be closer to the source of the lumber and will know whether pesti­cides are used where the wood was grown.

Wood Selection and Storage

Kiln-dried framing lumber is drier than air — dried lumber. It is therefore more true to size and less susceptible to shrinkage and mold infestation. Certified, sustainably harvested, kiln-dried framing lumber is now becoming widely available. Framing lumber of this type is currently slightly more expensive than stan­dard lumber, which is often logged using un­sustainable practices.

Wood may occasionally be delivered to the site containing mold. It can also become moldy while stacked onsite if it is unprotected. To avoid these problems, you should include the following instructions in your specifica­tions: [5] [6]

• Fir, spruce, and hemlock are preferred over pine where available at no additional cost to the owner.

• Wood stored onsite shall be protected from moisture damage by elevating it off the ground and covering it with a tarp during precipitation.

• Wood that becomes wet must be quickly dried by cross-stacking to promote aera­tion. It should have less than 16 percent moisture content, as tested by a moisture meter, and must be free of all signs of mold in order to be acceptable. (See Division 13 for moisture meter testing.)

Updated: 16 ноября, 2015 — 10:32 пп