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The Complete Water Shut Off Valve Guide - Plumb University

The Complete Water Shut Off Valve Guide

by Trevor Woods | Last Updated: August 1, 2020

You will have several different types of water shut off valves that regulate the flow of water in your home. And it can be confusing to tell what each valve controls and how it operates.

Our guide will walk you through the main water shut off valve through to fixture valves and everything in between. Going into details like what valves are used for, what they are made of, and where you find them inside and outside your home.

How Do Water Shut Off Valves Work?

Water shut off valves are designed to stop the flow of water. As a result, a shut off valve can isolate a plumbing fixture from the rest of the plumbing in your home or hold water back until you need it. Think of this like the difference between a shut off valve for your toilet that is normally open and your outside hose bib that is normally closed.

Shut off valves with a wheel or other multi-turn valves operate by spinning the handle. Turning the handle clockwise will tighten the valve stem inside and force a gate CLOSED or press a rubber gasket against a seat to restrict the flow of water. Alternatively, counter-clockwise will OPEN the valve and allow water to pass through the valve.

Ball valves or quarter-turn valves operate via a handle on the valve stem that pivots a steel ball with a hole inside to control the flow of water. If the handle is in-line with the valve body, the valve is OPEN and water flows through the hole in the steel ball. Conversely, when the handle is turned perpendicular to the valve the steel ball twists and STOPS the flow of water.

In our experience, quarter-turn valves are more expensive than multi-turn valves but tend to be more reliable. Whereas multi-turn valves are cheaper they typically require maintenance to keep them leak-free and functioning properly.

What Kinds Of Water Shut Off Valves Are There?

Water shut off valves typically come in two configurations: straight and angled.

Straight shut off valves are oriented so that the inlet and outlet of the valve are aligned and pointing in the same direction. You will typically find straight shut off valves on long sections of water pipes and where water lines come up through the floor to supply water to a plumbing fixture.

Angled shut off valves are positioned so that the inlet and outlet of the valve are at a 90°. You will find angled shut off valves at your laundry machine or where water lines extend out from a wall.

How Are Shut Off Valves Connected To Water Lines?

How you connect water shut off valves to your water lines depends on the material your pipes are made of.

PEX water lines can use shut off valves that are barbed and are crimped in place with a special crimp ring and tool. They can also use push-to-connect (also known as Sharkbite) fittings which bite down and compress an o-ring to create a water-tight seal. Compression fittings can also be found on PEX waterlines, which are installed with some basic hand tools.

Copper supply lines allow for the use of the same shut off valves as PEX with the addition of solder/sweat-on fittings. Soldering copper is a great method of installation but requires extra plumbing tools and supplies. You can check out our tutorial on solder copper here.

Chlorinated Polyvinyl Chloride or CPVC pipe is a strong and flexible plumbing material. Shut off valves on CPVC water lines are usually threaded, push to connect, or solvent cemented in place.

Older homes with galvanized steel piping will have the water shut off valves screwed on to threaded pipe sections.

What Are Water Shut Off Valves Made Of?

The most popular material for water shut of valves is brass. Brass is the material of choice due to its durability and reliability in residential plumbing systems. You can find brass shut off valves throughout your entire home.

Low-pressure water lines used in reverse osmosis systems, ice makers, aquariums, and hydroponic setups typically have shut off valves constructed of plastic or polypropylene.

Where Do I Find My Shut Off Valves?

Locating your water shutoff valves can be confusing. Individual shut off valves are usually found underneath or behind the fixtures and appliances in your home. These valves are conveniently located close by faucets and appliances to easily facility repair or replacement of these plumbing fixtures.

Where Do I Find My Main Water Shut Off?

Inside Your Home

Inside your home, the main water shut off valve is typically located along an outside wall that faces your street. Homes with basements allow you to trace back the water distribution lines back to the main shut off valve on the exterior wall or into a mechanical area for easy access. If you don’t have a basement, the main water valve might be concealed behind an access panel.

Plumbing Access Panel

Provides easy access to all types of hidden plumbing valves.

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It’s important to know where your main shut off valve is in case you need to turn off your water to make water line repairs or your neighbourhood is having water supply issues. Also, some insurance plans will have stipulations that require you to turn the water off to your home if you leave on vacation for more than 48 hours. It’s a good idea to check the fine print of your home insurance policy before you head off on holidays!

Your main water shut off valve will either have a multi-turn or quarter-turn handle. Both valves work equally well but lever handled valves are easier to visibly see if the valve is OPEN or CLOSED.

Outside Your Home

Outside your home is another shut off at the water meter or curb of your property. Some main water valves require specialized tools to turn this valve OFF and ON. This shut off is best left for professionals to operate and repair.

Protect Your House!

It’s a good idea to know where the outside main water shut off is in case of an emergency. Turning your water off from outside your home may be the best option when dealing with frozen or burst pipes.

What Type Of Water Shut Off Valve Do I Need?

The type of water shut off valve you need will depend on many factors. All shut-off valves are designed to stop the flow of water but not all valves are created equal. The shut of valve that best suits your needs will be based on the size of the waterline, the type of appliance it serves, and how the valve is operated.

For example, the shut off valve for your toilet will be entirely different from the valve for your laundry machine. One valve will be smaller and built with the ability to quickly connect with your toilet supply line. Whereas the other will be much larger and equipped with hammer arrestors to prevent the detrimental effects of water hammer.

The Common Types Of Water Shut Off Valves

Supply Stop Valves

Supply water stop valves are designed to control the flow of water to individual household plumbing fixtures. These valves are located nearby the fixture they serve as the water line enters the room through the floor or wall. You will find supply shut off valves in the cabinet below a sink or tucked away behind a toilet.

Individual shut off valves allows you to easily isolate the fixture for repairs without disrupting the flow of water to the rest of the home. Not all appliances are required to have supply stop valves but they are very handy to have at each plumbing fixture.

SharkBite Straight Shut Off Valve

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Stop Valve requires no special tools, no soldering, no crimping or glue. Just push to create a watertight seal.

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Sillcocks, Stopcocks, And Lawn Services

This category covers all your outdoor water faucets. Outdoor hose bibs come complete with a shutoff handle and a threaded spout to attach a garden hose. These outdoor water faucets conveniently provide water outside your home to tackle outdoor chores or to simply run through the sprinkler.

Hose bibs come in a variety of configurations and sizes. Each is designed to fit through a variety of outdoor wall thicknesses and some even prevent frozen and burst pipes.

Frost Free Sillcock

Installs in seconds!

The SharkBite Push-To-Connect Anti-Siphon Frost-Free Sillcock has a 1/2? push-fit inlet that is compatible with Copper, PEX, CPVC, or PE-RT pipes and a 3/4? MHT outlet.

The valve comes with an integrated mounting flange to secure it to the mounting surface. There is also an integrated air gap backflow prevention system to prevent any potential back-siphonage.

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Washing Machine Valves

Shut off valves for your laundry and clothes washing machines connect to your appliances via a flexible hose. Some varieties will be fitted to an outlet box equipped with a drain and hammer arrestors to protect your pipes from water hammer.

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The SharkBite Washing Machine Outlet Box is integrated with SharkBite ends to allow for quick and easy installation

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Drain Valves

Drain valves are found on water heaters and boilers for cleaning and servicing purposes. You can also find drain valves on lawn and sprinkler services so that these water lines can be blown out and winterized. Although drain valves spend most of their working lives closed, they should be exercised regularly to ensure they function properly.

Water Heater Replacement Drain Valve

Full port ball valve with a large opening to allow faster draining and fewer clogs.

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Speciality Shut Off Valves

These are the wildcards of the waterline world. Specialty shutoff valves include backflow prevention valves, pressure reducing valves, check valves, and zone valves found in hydronic heating systems.

It’s best to leave repair and replacement of specialty valves to professionals. Specialized plumbing valves play an important role in your plumbing system and incorrectly plumbed valves could lead to cross-contamination of your water supply or damage other appliances in your home.

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Take control of the flow of water in your house by learning how to identify and operate the different types of water shut offs. It’s amazing how a small piece of brass can affect the function and health of your home!

Don’t underestimate the value of your plumbing valves. To make sure that shut off valve function as they should, they need to be checked regularly. This will help you make small plumbing repairs or save your home in case of a burst pipe emergency.

Show your plumbing shut off valves some love!

Happy Plumbing!

Trevor Woods is the founder of Plumb University® and he started in the plumbing and construction industry in 1997. Since then, his mission is to make plumbing repair and maintenance easy for everyone. And each year, he continues to help more people with their plumbing installation, care, and troubleshooting.