Pressure treated (PT) lumber is wood that has been infused with chemical preservatives to protect the wood from rot and insects. The wood is placed in a depressurized holding tank that removes the air and replaces it with a preservative.

What does it mean when timber is treated?

Treated timber is pressure impregnated to guard against environmental conditions.

How do you identify treated timber?

Generally any softwood (pine) that has been in the open for more than a year and has not rotted will have been preservative treated. Any hardwood such as power poles which have intact sapwood (the outside of the tree) will also have been treated.