For rot to occur in wood, 4 elements must be present: temperature, oxygen, moisture, food source for living organisms. Pressure-treated lumber eliminates rotting and food source. The chemical most commonly used is chromated copper arsenate. For more information go to the American Wood-Preserver's Association.
CCA was phased out of residential applications back in 2003. The most common formulation for treated lumber today is micronized copper. It is commonly known as MCQ, MicroPro and ProWood Micro. The process used to make it has earned Environmentally Preferred Product status from Scientific Certification Systems. Learn more here:
ReplyDeletehttp://www.ufpi.com/product/pwmicro/
Dick Gauthier