Plastic. In the 1970s, ABS and PVC plastic plumbing pipes became commonly employed in residential construction. These plastics are resistant to many chemicals that would otherwise damage metal piping. The use of plastic plumbing pipes has many advantages for both homeowners and plumbers. Plastic pipes are much less likely to corrode than iron or steel pipes. This means that over time the appearance of a plastic water system will be improved while that of a metal one will deteriorate. The materials used to make plastic pipes are also very stable at high temperatures, which means that they won't break down when exposed to heat from hot water valves or drains. Finally, plastic pipes can be manufactured in a variety of sizes and shapes, which allows them to fit into confined spaces where metal pipes could not go. In conclusion, plastic plumbing is the ideal choice for any home built after 1970. Both consumers and manufacturers benefit from its use because it is durable, affordable, and easy to maintain.