Pressure treated plywood is an exterior grade plywood. Pressure treated plywood is subjected to pressure treatment with chemicals.  This treatment process helps protect plywood over its lifespan against rot and decay allowing for longer and more reliable lifespans.Pressure treated lumber has been used for decades in a wide range of residential, commercial, and industrial construction projects. The approved preservatives in pressure treated wood are specially formulated to protect against the elements and keep your home, office, barn, and other buildings safe, comfortable, and solid for decades to come. Pressure treated wood is the best option for a wide range of building applications. It is also required by local building codes for many types of construction projects. Pressure treated plywood is the preferred flooring material for an outdoor shed.It will resist decomposition from being exposed to wetness from either rain, dripping outdoor appliances like snow blowers, or tracked-in mud and moisture. In wet, foggy and moist conditions, a pressure-treated plywood floor is a must to maintain the integrity of the shed and the shed floor.When compared to more expensive building material such as concrete and steel,pressure treated wood is an exceptional value . Its high strength-to-weight ratio makes pressure treated wood perfect for load-bearing, structural applications and it costs less than other options. Plus, because pressure treated wood is easy to handle, transport, and store, it also costs significantly less to install.