Plastics can be used as building materials due to their beneficial properties such as strength, durability, resistance to water and corrosion, and low cost. There are two main types of plastics - thermoplastics, which soften when heated and harden when cooled and can be repeatedly reformed, and thermosetting plastics, which permanently harden during heating and cannot be remelted or remolded. Common applications of plastics in construction include pipes, cables, flooring, roofing, windows, and structural plastic composites reinforced with fibers.