How to Turn Off the Main Water Shut-Off Valve

In the event of a plumbing emergency, it is essential to know how and where to switch off your home’s main water supply, as well as the isolation valves on your several plumbing fixtures. A broken line, burst pipe, or sewage backup can cause severe damage to your home and possibly cost you thousands in water damage and water bills.

Being able to contain the situation as soon as possible hugely helps you with damage control, allowing a larger time frame for help to arrive (if the situation calls for it.) Also, if you are going to be away from your home for an extended period, then it is highly advised that you shut off the main water valve.

Where is the Main Water Shut-off Valve Located?

This is the million-dollar question. You can locate the main water shut-off valve in several different areas of your home.

  1. Basements
    • Check the interior wall near the front of the house, where the water comes in from the water meter. In other cases, the main water supply may enter in another area, like in a mechanical room, near the water heater or furnace, or up through the floor.
  2.  Crawlspace plus a Basement
    • You may find the shut-off valve where the water enters the basement, or for some older homes, the shut-off valve may be inside the crawlspace. If the latter is correct, you may want to consider a second valve located in a basement.
  3.  Crawlspace with No Basement
    • Usually located near the water heater or under the kitchen sink, but anywhere is possible. You may also find it in the crawlspace, in which case, you may want to consider a second valve located up in the living space — near the water heater or under a sink.
  4.  Slab-On-Grade Construction
    • You might locate it near the water heater, under the kitchen sink, or in the garage.

If you still cannot locate the shut-off valve, your trusted local plumber should be able to tell you where it is.

NOTE: Never touch the pressure regulator, located above the shut-off valve. Only a licensed plumber should adjust your water pressure.

How to Turn Off the Main Water Valve?

Once you find the shut-off valve, you will either hand turn it — clockwise for gate valves and vertically to the pipe for ball valves or use the proper tool depending on the design.

After you successfully shut the water off, it’s essential to release the pressure from your pipes by turning on the hot & cold faucets in your home.

NOTE: Only use your hand to turn on or off a damaged or corroded old water valves. If you are unable to do it by hand, call an expert plumber.

Always Remember:

Not only should YOU know how to turn off the main water shut-off valve, but you should ensure that every member of the family knows where to find it and how to use it. Additionally, it’s a great idea to put the plumber’s contact info near the shut-off valve. Tape his business card to the wall or place a tag on the shut-off valve. That way, you can reach a plumber quickly and keep plumbing problems from turning into a costly repair situation.

The best method to maintain a healthy plumbing system is to have a regular maintenance checkup done by a professional. Your licensed plumber will be able to perform a full inspection of your plumbing system to identify potential risks before they turn into major and emergency plumbing problem.

If you have any further questions about locating and turning off your main water valve, don’t hesitate to call Einstein Plumbing, Heating, and Cooling at 888-671-7767 or email [email protected]. We are your local plumbing professionals at Oregon, Washington, and Nevada, and we will be happy to help you with plumbing, water heater, heating & cooling, and sewer & mainline problems.

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