One fixture at a time
Sink, Toilet & Appliance Shutoff Valves
Find the small valve feeding your fixture, understand why it leaks or stops working, and see what goes into repair or replacement.
Find your fixture
Which valve
needs help?
A fixture stop is the small valve feeding a faucet, toilet or appliance. We repair and replace stops that leak, seize up or keep letting water through when closed.
The chrome handles at the back of this cabinet control the faucet’s hot and cold supplies.
Two supplies under the cabinet
The small valves where the hot and cold pipes enter the cabinet are called fixture stops. Short supply hoses connect them to the faucet. Close both stops for faucet replacement. For a leak at one supply hose, its own stop controls that side.
A stop that drips around the handle after turning needs attention. If water continues from the faucet after the line drains, one of the stops may be failing to seal.
One valve behind the toilet
The toilet stop feeds cold water through a hose to the tank’s fill valve. It is commonly low on the wall beside the toilet, or on a pipe coming through the floor. It needs to work before a toilet, fill valve or supply hose can be serviced.
Once the stop is closed, flushing uses the water stored in the tank. A tank that keeps refilling shows that water is still getting past the stop. A continuing running-toilet problem with the supply open usually starts with the tank’s internal parts.
Follow the small supply hose
A dishwasher commonly uses a hot-water stop under the kitchen sink. It may have its own valve or share a dual-outlet valve with the faucet. A refrigerator’s ice maker and water dispenser use a small cold-water line with a shutoff under the sink or behind the refrigerator.
On a dual-outlet stop, one handle may shut both outlets together; a two-handle version can control each separately. We trace the hoses so the valve being serviced matches the appliance.
Hot and cold at the washer box
Washing machines usually have two hose connections, supplied by separate hot and cold valves or a combined shutoff. Those valves get used when hoses or the machine are changed—often after sitting open for years.
We check for leaks at the handles, hose threads and pipe connections inside the box. A worn hose washer can leak at the hose connection even when the shutoff itself is sound.
Multi-turn or quarter-turn?
A multi-turn stop tightens a rubber washer against an internal seat as you turn the handle. Aging washers can harden, break apart or stop sealing. A quarter-turn replacement operates with a short rotation and is easy to use in a tight cabinet. The internal design depends on the product; BrassCraft’s G2, for example, uses a one-piece shutoff mechanism.
Angle stop or straight stop?
An angle stop turns the water path 90 degrees, usually from a wall pipe toward the fixture. A straight stop keeps the connections in line and often fits a pipe rising from the floor. We choose the shape that leaves the handle reachable and lets the hose curve naturally without a kink.
The connection at the wall matters
The short piece of pipe sticking out of the wall is the stub-out. A compression stop seals around copper with a metal ring called a ferrule; other stops attach with solder, threads, press fittings or a matching PEX connection. A damaged ferrule, short stub-out or corroded pipe can require work behind the old valve.
The valve and supply hose work together
We check the hose’s end seals, length and condition when replacing a stop. Older one-piece valve-and-hose assemblies are replaced together. A separate valve and replaceable connector make future faucet or toilet service easier. A cracked valve body, seized stem or damaged connection calls for replacement.
Read more: BrassCraft: quarter-turn fixture stops and connection types ↗ · BrassCraft: multi-turn stops and repair-part resources ↗
Can the little valve be rebuilt?
Some multi-turn stops can be repaired with a matching stem, washer and packing kit when the body and seat are sound. For a worn or unreliable stop, we usually discuss a new quarter-turn valve. Before removing either the internals or the valve, we shut off the supply ahead of it and relieve pressure.
Afterward, we check for leaks with the water back on, close the stop to confirm it holds, then reopen it and check the fixture’s flow. When both sink valves are the same age, we check the pair during the same visit.
Book fixture shutoff repair ↗See our washer-box shutoff installation
Our work / South Jordan
Hot and cold.
Both within reach.
This washer box has separate hot and cold quarter-turn shutoffs. The handles and hose outlets face into the box, with copper supply connections above.
Explore laundry & appliance plumbing →
A few useful answers
Common questions.
Do I need the whole house shut off to replace a toilet stop?
Replacing the toilet’s shutoff valve requires a working valve ahead of it, usually the house main. Once the new toilet stop is installed and tested, it can isolate future toilet or hose repairs by itself.
Do both valves under a sink need replacing?
We check both. When they are the same age and both are stiff, leaking or unreliable, replacing the pair can save a second shutdown. A sound valve can stay when the problem is confined to the other side.
Sources & public guide record
Maintained by Mountain Man Plumbing · Utah Master Plumber, Lic. #12992295-5501.
- BrassCraft: quarter-turn fixture stops and connection types ↗
- BrassCraft: multi-turn stops and repair-part resources ↗
Guide version 2026.09.10.1 · References checked 2026-09-10.