Plumbing is an important part of a healthy home. Use this advice to keep your home's plumbing safe for your family.Plumbing includes all of the water supply and water waste lines. When the home's foundation is built, a plumber runs a supply line from the street through the foundation wall or the slab. From that point, they run the lines that supply water to the home to rooms where sinks, bathtubs, showers and other fixtures will be installed.