Homes Built on a Slab
If your house is on a slab (houses built on a slab lack basements or crawlspaces, and there is no space under the floor), your main water shut-off valve should be close to your water heater tank, either below it or at the top.

Homes With a Crawlspace
Your main water shut-off valve could be located under a crawl space. You can typically find it along the front wall of the house.

If you still are not sure where to find your main water shut-off valve, start looking along the perimeter of your home interior, to locate where the plumbing enters your home. If you locate your water meter, the plumbing probably will run from there to the closest part of your home’s perimeter.

Homes With a Basement
If you have a basement, that is the most likely place you’ll find your shut-off valve. Most water basement shut-off valves will be in the same place as your outdoor hose bib, just on the inside of the exterior wall. The simplest way to find the valve is to visualize where the hose attachment is on the outside of the house. Then find the matching spot on the wall inside the house.

There are two types of main shut-off valves, a ball valve, and a gate valve. A ball valve looks like a ball with a hole in the middle of it. As you rotate the lever handle to turn the valve on, the hole in the ball aligns with the water pipe and lets the water flow freely. When the valve is in the closed position, the ball blocks the pipe. Turn the handle 90 degrees right to shut off the valve or turn it 90 degrees left to open it.

Gate valves have circular handles that regulate a gateway that travels up and down inside the valve to either allow or block the flow of water. You can adjust the flow of water or turn it off completely. Rotate the handle counterclockwise as far as possible to open it and rotate it clockwise to close it.

Fixture Isolation Valves
If a specific fixture is leaking, like the toilet, bathtub, sink, or washing machine, you can search nearby along the wall or beneath the fixture for an isolation valve to shut off the water to that specific plumbing fixture.

To turn off the water to a toilet, you can typically locate the water supply valve on the wall or floor adjacent to the toilet. You can turn the shut-off values for a bathtub if you can gain entry to the plumbing via an access panel. You will find shut-off valves for hot and cold water under the kitchen or bathroom sink. For a washing machine, look for shut-off valves behind or just above the unit.”

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