The 7 Most Commonly Used Valves in Residential Plumbing

The purpose of valves is to stop and regulate the flow of water, and each type has its benefits and disadvantages. The majority of valves in a residential plumbing system are part of the water supply system, which controls the flow of pressurized water from a water utility or a private well. They may be designed for simple ON-OFF control of the water flow, or they may be designed for adjusting the volume of the flow, depending on the valve's design.

In addition to bronze, brass, and PVC plastic, most valves are available in a variety of materials. Make sure the materials used in the plumbing system are appropriate for the type of pipe.

Gate Valve

Among the most commonly used valves in plumbing are gate valves. An internal gate is raised or lowered through a knob or twist-type handle located at the top of the valve. You should never use gate valves to control the volume of flow. They are designed to be fully open (allowing full flow) or fully closed (stopping the flow entirely). These valves can be worn out if they are used to adjust the water flow. It is common to use gate valves as shutoff valves on main and branch water supply lines, although ball valves are gradually becoming more popular in these applications as well. Gate valves are reliable for shutting off the water supply, and they are often used on water mains and branch lines. It is not uncommon for a gate valve to get stuck in an ON or OFF position due to corroded internal metal parts. Most commonly, they are used where water needs to be shut off only occasionally.

Ball Valve

For main water shutoffs and branch line shutoffs, a ball valve is perhaps the most reliable type of valve. In the same way as gate valves, ball valves are all-or-nothing valves - they should either be fully opened to allow full flow or fully closed to prevent any flow. The inner ball of these valves has a hole in the middle, which is connected to the outer lever handle. When the handle is parallel to the water supply pipe, the valve is open; when it is perpendicular, it is closed. It serves as a handy visual aid for indicating whether the water is on or off.

Butterfly Valve

Butterfly valves are similar to ball valves in that they have a lever-type handle that opens and closes the valve. To regulate the flow of water, a metal disc rotates internally. Even when the valve is fully open, water flow is reduced somewhat due to the flow around the disc, which is located at the center of the valve. Unlike a ball valve, which is designed as an ON-OFF valve, a butterfly valve can precisely adjust the flow volume. The gasket inside a butterfly valve can present maintenance issues after a few years, which is one of its notable drawbacks.

Generally, butterfly valves are used in industrial applications and are not commonly found in household plumbing systems.

Globe Valve

A globe valve regulates or throttles water flow in plumbing applications. The bulge in the body of this type of valve gives it its name, a shape not found in other types of valves. Globe valves usually have twist knob handles.

It is usually necessary to install globe valves when the flow of water needs to be controlled or adjusted regularly. In the internal design, a stopper is located on the end of a valve stem, which can be raised and lowered using the valve's twist knob. Upon forcing the stopper against the interior valve seat, water flow is completely halted. By incrementally raising the stem away from the valve seat, the flow of water can be precisely controlled.

Globe valves are used for outdoor faucets (hose bibs) and similar utility faucets because they are good at regulating flow.

Pressure Reducing Valve

The purpose of water pressure-reducing valves in plumbing systems is to reduce the overall water pressure to acceptable levels. They are usually equipped with a spring and diaphragm that are adjusted depending on the water pressure. 

Rather than opening and closing the water flow, pressure-reducing valves throttle it down to reduce overall water pressure. Usually, they are used in homes that receive relatively high-pressure water from the municipal water supply, where the pressure may cause damage to appliances and plumbing systems.

Fixture Shutoff Valve (Stop Valve)

Small valves with twist handles or knobs are used to shut off water flow to individual plumbing fixtures, such as faucets and toilets. Straight valves and 90-degree angles (also called angle valves or angle stops) are available. By using shutoff valves, you can work on a faucet or other fixture without having to shut off the water to the entire house.

In appearance, fixture shutoff valves resemble small gate valves, since they usually have a knob or wheel that turns to open and close the valve. The internal design of fixture shutoff valves can vary. The valve handle opens and closes a simple compression washer against the valve seat in some types. In a diaphragm design, the valve stem controls a flexible diaphragm that presses down against a valve seat opening to stop the flow of water.

Check Valve

A check valve keeps water flowing in one direction only and prevents it from flowing in the opposite direction. Because most types are not operational, they do not have control handles. Check valves are often found on outdoor faucets (hose bibbs) and lawn sprinkler systems, such as back-flow preventers. Different types of check valves have different inner mechanisms, such as ball checks and diaphragm checks. Stop-checks are operational check valves that can completely stop all water flow in both directions.