Find the shutoff
before you need it.
The useful valve is the one you can find in the dark. Most people meet theirs for the first time while water is already on the floor.
In a single-family house the main is often where the line enters: a garage wall, a closet on the street side, or a box in the parkway near the meter. The house valve and the meter valve are not the same. The meter valve belongs to the supply up to that point. The house valve is yours, and it is the one you should be willing to turn. Clockwise closes it. A quarter-turn ball valve stops at a right angle. A round gate valve needs several turns and should not be forced if it has not moved in years.
How you know it worked
Open a cold faucet at the top of the house after you close the valve. The flow should fall off to a trickle, then stop. If it does not, you closed a branch, not the main, or the valve is no longer sealing. Do not keep leaning on a frozen handle until the stem snaps. A broken shutoff in the middle of a leak is a worse night than a stiff one.
Apartment and condo stacks are different. The valve in your kitchen may stop only that fixture. The riser valve may be in a locked closet or on another floor. If you do not know which one is yours, say so when you call. We would rather meet you at the right door than talk you through a valve that serves six units.
Ball valve, gate valve, and the one at the meter
A ball valve is a lever. Inline with the pipe, it is open. Across the pipe, it is closed. It is the one you can operate in a hurry. A gate valve is a round handle that takes several full turns. Older houses have them, and many have not been moved in a decade. Turn one gently. If it stops hard before it should, or the handle spins without the water changing, leave it and use the meter valve rather than snapping the stem. The meter valve usually wants a key, the slotted tool that sits in the parkway box. If you do not own one, a plumber does. Forcing that valve with pliers rounds it off and leaves you with no shutoff at all.
There is often a second valve you will mistake for the main: the cold inlet on top of the water heater, the valve at a softener, the irrigation shutoff where the line tees off to the lawn. Closing those is still useful. It is not the same as stopping the house. After you close a candidate, open a high cold faucet. If the flow dies, you found it. If a hose bib on the opposite side of the house is still live, you found a branch.
Make it findable
Tag the valve the day you confirm it. A piece of tape and the word “main” is enough. Show the person who has a key. In a condo, ask the manager which valve is yours and which kills a riser for other units, and do not experiment on a riser to find out. If the only shutoff is seized, that is a repair to schedule on a quiet afternoon, not a discovery to make during a burst. A house with no working main is one failed fitting away from a long night.
Related service: Leaks and burst pipes. For the visit itself, call 818-631-7296 or send the address.