Out of sight, out of mind. Most of us don't think about our home's plumbing system--hot and cold water, toilets, drains, etc.--until something goes wrong. Most of it is hidden in walls or under cabinets. Fortunately, the parts that need fixing are easier to get to. Let's take a closer look at your home's plumbing system.

How Does It Work?

Components of a typical residential plumbing system.

A household plumbing system is the series of pipes, faucets, drains, and their attached devices and fixtures that bring fresh water into a home and take waste water out to a sewer or septic system. Whether the water comes from a municipal system or a private well, water comes into your home through a large pipe. If you purchase your water, a meter on the pipe records your usage. Near the meter is a shutoff valve for turning the water supply off before it enters the house.

When the water comes into your home, one pipe branches off to the water heater to supply hot water to various fixtures. The rest of the (cold) water continues on to the fixtures and appliances. Water in those supply lines is under pressure (about 50 pounds per square inch (psi) so that it will flow rapidly when you open a faucet or turn on a dishwasher or clothes washer.

Other, larger pipes and related drains collect wastewater from those same fixtures and appliances and conduct it to a main sewer or septic system.

Caution!

Make sure you know where the shutoff valve is so you can minimize water damage in an emergency.

What Can Go Wrong?

Pipes can leak or break. Fixtures and appliances can also leak. Drains sometimes don't drain or drain slowly. Fixtures and pipes also get clogged.