The Basics of Plumbing

Plumbing is a trade that involves the installation of pipes and fixtures for the delivery of water and the removal of waste. Plumbers often work with hazardous materials and must follow strict safety guidelines.Plumbing

Combined sewers are large underground channels that carry both rainwater and wastewater (sewerage). When it rains heavily, the volume of runoff can exceed the capacity of the pipe, and the sewage may overflow into streets and homes. Visit to learn more.

The plumbing system in your home delivers fresh, clean water for drinking and cooking and removes waste and sewage in an efficient manner. While it may seem like a complex network of pipes, fittings, and fixtures, the basics are straightforward. The system is comprised of two subsystems: the water supply system and the drain-waste-vent system. Understanding the difference between these systems can help you identify potential problems and make informed decisions about repairs and maintenance.

The water supply system brings freshwater into your house from the municipal water line, private well, or rainwater collection system. It delivers it through a main line that connects to your home’s water meter and then branches out to faucets, toilets, showers, and other fixtures. It also feeds your home’s water heater. Your water meter measures the amount of water that flows into your house, which helps determine your bill. The water supply lines are typically made from plastic, iron, or copper. The water meter and main line are typically located in the basement or near the street.

In most homes, the plumbing system includes separate hot and cold water supply lines for the kitchen, bathroom, and laundry room. The hot water supply line typically leads to your home’s water heater, which supplies all of the sinks and other fixtures with hot water. The cold water supply line usually leads to your outdoor faucet, which provides a means for you to connect a garden hose for watering your lawn and garden.

Each fixture in your house is connected to the water supply piping by either a flexible connector or a rigid pipe. Flexible connectors can flex to join different types of pipes, while rigid pipes are designed for fixed connections. The type of pipe you have determines its durability, efficiency, and cost. The best pipe for your home depends on where it will be installed and the types of fixtures you have.

The plumbing industry has evolved over time to meet changing needs. In ancient times, the systems that provided clean drinking water and removed waste were complex, but they eventually became more manageable. Today, plumbing is considered a vital part of any building. It’s important to maintain your plumbing system to avoid costly repairs and protect your health.


The drainage system of a plumbing system removes excess water from the ground surface and subsurface. This artificial removal of moisture protects the structure of buildings and other infrastructure and also prevents the contamination of soil by trade or domestic waste. Drainage systems can be used to achieve a variety of purposes, including construction site dewatering, land cultivation, landscaping, and stormwater management. The type of drain used varies according to the purpose. Drain pipes can be made of clay, concrete, or flexible plastic. The choice of material depends on the environmental and financial constraints of the project. For example, clay and concrete drains are more environmentally friendly than flexible plastic drains. However, concrete and clay pipes are more expensive to install than plastic pipes.

The drains of a house are part of the plumbing system and carry waste water from toilets, baths, and sinks to the sewer line. The wastewater is then transported to a sewage treatment plant or septic tank. The plumbing system of a house must be designed to ensure that the pipes do not become blocked or clogged with debris. It is also important to maintain good ventilation in the house to prevent foul odors and mildew.

In the case of a residential building, the drainage system is typically composed of a main sewer line and lateral drains. The main sewer line usually runs horizontally, with a slight downward slope, under the lowest floor of the building to the municipal sewer line or septic tank. The lateral drains carry wastewater from all of the household fixtures to the main sewer line.

It is essential that plumbing contractors choose the appropriate materials for a drainage system to avoid costly problems. Using the correct type of drain for the project helps reduce maintenance costs and extend the life of the system. It is also important to use a high-quality product that has been tested and approved by an independent authority, such as the WaterMark certification scheme. The WaterMark stamp is printed on all certified products, so customers can be sure they are getting a quality product.


A plumbing system must be properly vented to prevent traps from siphoning dry and allowing sewer gas into the building. The venting system consists of pipes that lead from an air inlet at the roof to various points within the waste system. The pipes ensure that a sufficient amount of air enters the traps to maintain their water seals, compensating for pressure variations that can cause them to dewater and reintroduce sewer gases into the building.

Traps must be protected from air infiltration because high concentrations of sewer gases present a health and fire hazard. This can be accomplished by maintaining a continuous supply of water in the trap or by using a chemical inhibitor such as mineral oil. It is also important to ensure that the waste line is not sealed too tightly. A tight seal can allow water to flow past the drain and blow out the air seal, resulting in a wet vent.

A wet vent can also occur if the pipe connecting to a fixture is not adequately sized. This is particularly common with toilets, which can aspirate large amounts of water and subsequently blow the air seal. To avoid this, the plumbing codes specify minimum vent pipe sizes.


Plumbing uses pipes, valves, and fixtures to convey hot water, steam, and air for a variety of functions in homes, offices, and other buildings. Its ability to provide clean, drinkable water and remove waste has likely saved more lives and extended life expectancy than any other medical advancement in history. Plumbing also brings comfort to living and working spaces by providing warm showers, relaxing baths, and soothing surroundings. In addition, plumbing can deliver a number of energy-saving benefits by controlling the flow of water and reducing heating costs.

Although a college degree is not necessary to become a plumber, the trade requires a great deal of specialized knowledge and training. Many plumbers learn through a combination of on-the-job experience, classroom instruction, and hands-on training at a vocational school or community college.