Plumbing is the set of pipes and fixtures that convey water throughout your home. The system is designed to bring fresh water in and take waste water out. This includes the hot and cold water that runs through your faucets, showers, baths, and toilets. It also includes the drainage system that takes wastewater away from your fixtures and directs it to a septic tank or city sewer line.
While the terms “plumbing” and “drainage” are often used interchangeably, they actually have very different jobs. A plumber works on the water supply and drainage systems, while a drain cleaner deals with clogged sewer lines.
The most common material for residential plumbing is galvanized steel pipe, which comes in a range of sizes and grades. It has standard tapered male threads that connect to female tapers on elbows, tees, couplers, and valves. The threads are plated with zinc, which prevents corrosion and helps the pipe retain its strength. Galvanized steel is less expensive than copper, but it can be more difficult to work with. It requires a special tool called a pipe threader to make changes in the plumbing.
Another option for residential plumbing is polyethylene (PEX), which has high-pressure ratings, fewer fittings, and is highly resistant to freezing and corrosive chemicals. It is also flexible, so it can adapt to changes in temperature and pressure. It is not recommended for repiping, though, as it is susceptible to rupture under certain conditions.