Plumbers install pipes for water and their drains as well as gas and waste systems in a dwelling, business or industrial facility. Plumbers install bathroom appliances such as showers, toilets, sinks, and kitchen apparatus such as dishwashers. Water heaters and heating provided by plumbing as well as any piping required in a new or remodeled houses or buildings.

Plumbing installations and repairs are subject to state or local township codes depending on the size of the project. There is a national plumbing code in addition to state and local coding. These regulations must be followed as a regular practice and are taught to apprentices during their education.

Before installing any kind of plumbing systems a licensed plumbing contractor should be hired to design and install or supervise installation of an up to date plumbing system designed specifically for the building be constructed or repaired.