Plumbers are skilled professionals who are trained to install and maintain pipes and systems for drinking water, sewage and drainage. They usually have trained through four- to five-year training programs, which include apprenticeships, via trade schools and community colleges. Plumbers’ areas of expertise typically go beyond pipes to include mathematics, blueprint reading, plumbing codes and water distribution. They handle plumbing emergencies, such as broken pipes or clogged drains, and install and maintain everything from a new piping system to a replacement faucet. Plumbers also know how to install bathtubs and showers, toilets, water heaters and dishwashers. Plumbers may work on residential or commercial sites, sometimes designing and laying out a pipe system during construction.
Let's start with the easiest possible project: Installing a new shower head is as simple as it gets. Typically, all you have to do is unscrew the old shower head from the shower arm (the pipe coming out of the wall), clean off the threads on the shower arm and wrap a bit of Teflon tape around it, then screw on the new shower head. It's really that simple (and if you don't believe me, check out the video above from Dummies.com). Do read the installation instructions on the shower head you buy, though. Some are designed not to require Teflon tape and can actually leak if you use it.
Before you get involved with most plumbing projects, you'll need to shut off the water flowing to whatever you're working on. Most of the time, there are easy-to-access gate valves or compression valves that you can turn with your hand. Turn them clockwise all the way to turn off the water and counter-clockwise to turn it back on when you're done. For sinks, look under the sink and you'll usually see two valves—one for hot water and one for cold. On kitchen sinks, you might also see valves for the ice maker on your fridge or your dishwasher. Just turn them all off. For toilets, the valves are on the wall or right on the pipe behind the toilet.
Don’t flush floss, tampons, or even so-called “flushable” wipes. They don’t break down like toilet paper does and can come back to haunt you later. “Toilets are more water-efficient now than they were 20 years ago, so there sometimes isn’t enough volume in the flush to force debris down,” says Marcin Wroblewski, president of ExpressRooter Plumbing in Toronto. “An object will get lodged in the trap and cause blockage when waste builds up days later.”
The straight sections of plumbing systems are called "pipes" or "tubes". A pipe is typically formed via casting or welding, whereas a tube is made through extrusion. Pipe normally has thicker walls and may be threaded or welded, while tubing is thinner-walled and requires special joining techniques such as brazing, compression fitting, crimping, or for plastics, solvent welding. These joining techniques are discussed in more detail in the piping and plumbing fittings article.
Plumbing originated during ancient civilizations such as the Greek, Roman, Persian, Indian, and Chinese cities as they developed public baths and needed to provide potable water and wastewater removal, for larger numbers of people. Standardized earthen plumbing pipes with broad flanges making use of asphalt for preventing leakages appeared in the urban settlements of the Indus Valley Civilization by 2700 BC. The Romans used lead pipe inscriptions to prevent water theft. The word "plumber" dates from the Roman Empire. The Latin for lead is plumbum. Roman roofs used lead in conduits and drain pipes and some were also covered with lead. Lead was also used for piping and for making baths.