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Understanding Household Plumbing Systems

Understanding your home’s plumbing system is important. It will help you reduce the risk of plumbing emergencies and understand how to repair them yourself when they occur.

Despite its complexity, Plumbers In Berea Ohio adheres to nature’s basic laws of gravity and pressure. In this article, we’ll explore two subsystems that carry fresh water into your home and drain wastewater away: water supply systems, and drainage systems.

plumbing system

Water Supply System

The water supply system delivers fresh water into your house and gets wastewater away. It’s a series of pipes, valves, and fittings that deliver running water to every tap in your home, hot showers, washing machine, outdoor spigot, toilet, and more. It’s important to know the basics of your plumbing so you can understand how it works and help a plumber fix problems.

Your freshwater comes into your house under pressure via the humongous pipe, called the main pipe, that runs parallel to your street. From there, it goes through a meter that registers how much you use and then into your house to reach the faucets and appliances that need it. There is usually a shutoff valve right before and after the meter, which allows you to stop the flow of water should the need arise.

Depending on your setup, you may have a direct cylinder system or an indirect cylinder system. Indirect cylinder systems are more common in older properties, where a large cold water tank is fitted in the loft and heated by a combination boiler. These tanks are prone to leaking and take up valuable space, but they can be cheaper to run than direct cylinders.

To get the most out of your plumbing, you need to understand how it’s balanced between two subsystems – the water intake and the drainage system. Both systems follow basic laws of nature, including gravity and the principle that water seeks its level.

Drainage System

Your plumbing system’s drains are responsible for taking wastewater away from your house. It’s a separate system that doesn’t use pressure but relies on the natural slope of your home’s pipes to move wastewater out of your fixtures and into a sewer line or, if you live in a rural area, a septic tank.

Just like the water supply system, the drainage system is comprised of pipes, valves, and fixtures. These parts work together to create a well-functioning drain system, also called the drain-waste-vent (DWV) system. Pipes, for instance, are usually made from PVC or copper. The materials chosen for your plumbing system affect how well your system functions. PVC pipes are lightweight, easy to work with, and highly durable. Copper, on the other hand, is more expensive and requires soldering to join its components.

As water moves through your pipes, it’s carried to fixtures like sinks, toilets, and washing machines by a series of valves and fittings. Each fixture has a drain, which is where wastewater flows once you’ve finished using it. The drains are shaped to hold water, forming a trap that keeps sewer gases from seeping into your home. The angled pipes that lead out of your trap are called vents.

The drain system also includes a waste pipe, which carries waste into the sewer line or, in rural areas, the septic tank. The vents allow air to enter the pipes to keep water flowing properly, and they’re also used to prevent wastewater from backing up into your house. If your drains aren’t used often enough, their traps can dry up and create a backflow that causes sewage odors to enter your home. To avoid this, you should pour water down your drains every once in a while to refill the traps.


The plumbing system comprises two distinct systems that bring clean water in and take waste out. Each of these is a separate set of pipes, but they share a few common components. Understanding the basics of how plumbing works will allow you to troubleshoot problems more effectively and maintain your home’s pipes, fixtures, and appliances.

The water supply system is the piping that brings in fresh water from your home’s municipal or private water source. It carries water at 50 to 60 psi of pressure, which is enough to move your water from the source to any room in your house. It also carries your household electrical appliances like washing machines, dishwashers, and electric water heaters.

While your water supply system is pressurized, the drainage system relies on gravity to carry wastewater out of your home. The drain line from each fixture (like a sink, shower, or toilet) connects to horizontal branch drain lines concealed within your walls. These drainpipes have curved sections known as traps that prevent wastewater and foul gases from rising back up into your home. The drain line then flows into the main sewer or septic tank.

The drain-waste-vent system is one of the least visible parts of your plumbing, but it’s also one of the most critical. Without it, your home’s sanitation would be compromised by sewage and wastewater seeping back up through faucets, showers, and toilets. The vent system consists of capped vertical pipes that connect each fixture to the drainage line and allow air to enter the pipe, maintaining proper pressure. It also allows sewer gases to escape. Most vents also feature an air chamber that cushions the impact of sudden turn-offs to fixtures, preventing the water hammer that can damage pipes and fittings.

Water Meter

Water metering is a system that measures your household water usage and charges you per cubic foot or 7.48 gallons of water consumed. It’s the only system that accounts for all of your water use and gives you accurate information about your monthly bill.

The freshwater subsystem pushes water under pressure through pipes to supply your upstairs fixtures, and the wastewater subsystem transports your used water away from your house. Your water meter is the heart of this system, and understanding how it works will help you save money on your next utility bill.

When water enters your building, it passes through your water meter, which spins a built-in device to measure the amount of water used. Each full rotation of the dial on a standard meter represents 1 cubic foot of water or 7.48 gallons. The water meter also has a sweep hand to display the current total water usage. Modern meters typically have a digital display with odometer-style wheels that add to show your usage.

To read your water meter, turn off all indoor and outdoor water-using devices like toilets, faucets, irrigation spigots, and icemakers. Then, observe the meter and record the numbers displayed. If the number indicated by the sweep hand is moving, it indicates a continuous leak. If the number is not moving, it’s an indication of no water flow and you’ll need to call a plumber.

If your meter has an indicator, it’s important to learn how to read it, as this will help you understand your bills and identify any problem areas quickly. A typical water meter displays two different numbers: the meter reading and the flow rate. The meter reading tells you how many cubic feet of water have been consumed since the meter’s installation. The flow rate tells you how many gallons are flowing through the meter at any given moment.

Shut-Off Valve

A home plumbing system might seem complex and intimidating, but it works mostly on basic principles like gravity and water pressure. Understanding just a few key concepts will help you navigate this intertwined network like a pro.

A good place to start is by familiarizing yourself with the location and function of your house’s shut-off valves. There is one that shuts off the supply to your entire house, and you may also have individual fixture valves (with twistable handles or knobs) that allow you to work on a single toilet or sink without closing the main valve for the whole house.

There are many different types of shut-off valves, but the most common ones are gate valves and ball valves. Both feature an internal “ball” or “hub” with a hole in it that pivots into a straight or perpendicular position to open and close the valve. These valves are usually soldered or solvent-glued onto copper pipes, and they can either be “normally open” or “normally closed.”

Most drain-waste systems feature a separate clean-out plug that you can open to clear out stubborn clogs without opening your main drain pipe. These are typically found in the basement, but sometimes in other parts of the house as well.

If you’ve been following the news, you may have heard about the YouTube video that went viral a few years back of a handyman who forgot to turn off the main water shut-off before working under his kitchen sink to fix a leak. This simple mistake resulted in a ferocious 90 PSI of hot water shooting out the bottom of the cabinet and flooding the entire apartment. By knowing where your shut-off valves are and how to use them, you can prevent similar mishaps.