For most of the 20th century treated lumber has been pressurized to impregnate the wood with chemicals preserving the lumber from pests, water, and rotting. In the 1980's extensive studies about the harmful nature of the chemicals being used in Chromated Copper Arsenate (CCA) processing began to flood the Environmental Protection Agency. These chemicals were extremely harmful and are what most people think when they hear pressure treated wood. However, at the end of 2003 the Environmental Protection Agency outlawed the production of CCA wood. Pressure treated wood is now using newer preservatives which have shown to not be harmful to the soil but still have many of the benefits.
Pressure treated lumber resists the damage caused by insects, pests, and fungal decay for decades. The preservative per cubic foot (pcf) standards printed on the wood can give consumers an idea of how much and what kind of preservative is left in the wood creating the resistance level. From termites to ground contact and even submersion in sea water, pressure treated lumber can be impregnated to withstand most conditions improving the life of the lumber.
Treated wood is initially more expensive than other lumbar, but in the long run the project will not need to be reassessed, rebuilt, or remodeled because of environmental strain on the wood. By only having to build once, hundreds of dollars can be saved not to mention the time and stress savings. Due to the longevity and durability of pressure treated lumber, the structure will not need to be redone for decades, making it an easy choice for anyone's budget.
Though rarely included as a "green" product, the environmental benefits should not be overlooked. Not only does the preservative process take less energy than alternative building products, but through treatment, treated lumbar can last much longer than other choices, putting less strain on our forest and fossil fuels due to less transportation. Secondly, the major chemical in treated lumber is copper (mainly copper azole and alkaline copper quaternary), which largely comes from recycled sources and would be thrown away as waste. No waste water discharges are produced when treating and air level pollutants are classified as "insignificant."
Though all wood needs to be cleaned, pressure treated lumber will not succumb to rot even when directly placed on the ground. Termites and other insects will not destroy the foundations. Fungal diseases will not penetrate and burrow into the structures. Depending on the type of lumber purchased, some treated lumber even comes with water resistant coatings to discourage warping. All these added benefits make for a very low maintenance structure and make the care process much ease for the builder or home owner.
New technology offers wood treated by micronizing copper instead of using a solvent. The process of micronizing eliminates the corrosive properties and required special fasteners when using pressure treated wood. Standard, hot-dipped, galvanized fasteners can be used without issue and even aluminum fasteners can be used with micronized copper treatments without worry.