what is pressure treated wood

Pressure-treated wood is a type of lumber that has undergone a process of injecting preservative agents into the wood fibers using high pressure to extend its useful lifespan. The preservatives used in treated wood are alkaline copper quaternary (ACQ), copper azole (CA), or micronized copper azole (MCA), which react with the wood fibers to slow natural decay and resist fungus, moisture, and other elements that promote rot and cause structural degradation. Pressure-treated wood is ideal for exterior building projects or projects requiring fire-retardants, such as framing, decks, porches, railing, fencing, sheds, garden boxes, landscape walls, arbors, gazebos, swings, sandboxes, and more. There are two basic types of pressure-treated wood: above-ground and ground-contact. The former is suitable for decks, fences, and other outdoor structures that are exposed to the elements, while the latter is ideal for posts and other applications that are in contact with the ground. Pressure-treated wood is recommended for many outdoor projects, but there are other applications where it offers effective solutions. It is important to note that all chemical preservatives used in treated wood are registered pesticides and regulated by the US EPA