An engineered wood product, plywood is often used in the construction industry (also called plies, hence the name). Plywood has a cross-grain pattern because it is made up of thin veneer sheets. Stability and strength are improved by the board's criss-cross structure. The highest quality of ply, marine ply, is watertight. We've gone through the many types of plywood and its properties so that you can make an informed decision about which one to use in your home. Water-resistant or waterproof boards are a good option if you live near the ocean. However, it can withstand a conflagration long enough for inhabitants to get out safely before it burns to the ground.