Main Water Shut Off Valve is Key to Shutting Down a Costly Catastrophe
The main shut off valve turns off all water to your entire house. Or if you live in a condo or apartment, the main shut off valve may actually turns off water to the entire building.
Do you know where the main water shut off valve is located? Have you tried shutting it off lately?
Your home’s water shut off valve is key to preventing a major plumbing crisis. So you should know where it’s located, what it looks like and how to turn it off and on.
Why You Need to Know About Your Main Shut Off Valve
In short, the time it takes to find and turn off the main valve during a plumbing crisis can mean thousands of dollars in water costs and damages to your home and possessions. So this plumbing advice is part of upholding my promise to share tips (read more here) that save you money and reduce your stress.
Here’s a few situations in which you’ll want to find and shut off your main water shut off valve ASAP:
- if a water pipe suddenly springs a leak
- if you’re attempting a DIY plumbing project. For example, imagine replacing a faucet, and the stop valve connected to that old faucet breaks while trying to turn it off. Believe me, those old stop valves break more often than you’d think).
- Was your home, condo or apartment was built with automatic sprinkler system? (Automatic Sprinkler Systems became mandatory in January 2010 in California) Like any other appliance, sprinkler systems can become defective and suddenly spray down water.
Turn the Main Water Shut Off Valve Off and On Occasionally
It’s easy to forget all about water main shut off valve. After all, you seldom need and most likely never installed it yourself (unless you’re a contractor or plumber). That’s why the majority of folks don’t even know where it is or what it looks like or for that matter why they should care.
Here are the two most likely styles you have in your house. One of these types of main water shut off valves is usually located on an outside wall or in a utility closet.

If it’s a “Gate Valve” as shown here, it will likely last for many years. But the down side of gate valves is that they can also become very difficult to turn after not being turned for years. So if your water shut off valve looks like this one, try turning it off and on NOW. It’s much better to find out that you can’t turn it with your bare hands now than when your home and property gets soaked in water.

Shut-Off Valve
The water shut off valve shown here is called a “Ball Valve”. This valve is open when the handle is aligned with the pipe. To close it, just turn the handle one quarter turn clockwise so that it’s at a right angle to the pipe. Since it’s a lever-type action, it’s easier to turn off and on with your hangs. It doesn’t freeze up as often when not used, but it’s still a good idea to turn it off and on occasionally just to be sure it’s in good working order before you need it.
Ball Valve in “On” Position

Ball Valve in “Off” Position

Do a Dry Run, Turning your Main Water Valve Off and On During Weekdays
Whenever you try to turn an old water valve off, there is always a risk of a it breaking. That’s true of stop valves connected to appliances (such as faucets and toilets) as well as the water main valve. Even if you successfully turn it off, an old frozen valve may also break off when you try to turn it back on.
So always do your dry runs during business hours. That way if the unthinkable happens, you can get a plumber without an emergency service call.
How about everyone who lives with you. Do they know where the water shut off valve is located and how to shut it off? They should.
Everyone in House Should Know About the Main Water Shut Off Valve
Send them a link to this page and later ask them to find it and shut it off and on. Yes, that would be a test. Better to test BEFORE you’re laying underneath a bathroom cabinet trying to DIY replace an old faucet and the faucet’s stop valve breaks. Yes, it happens.
When it does, water gushes onto your face and into the cabinet.
You’ll be yelling for the closest kin nearby to run out and turn off the main water valve. If they quickly follow your command (after they stop laughing and turn off the video they were recording on their cell phone) you’ll be glad you held a dry run.