How Do You Stop Water in a Building?

The most common way to stop water in a building is to shut off the main water supply valve.

Here's a breakdown of how to do it:

Locating the Main Water Shut-Off Valve

Inside Meter Box: Often found inside a box, usually located near the street or sidewalk. You'll need a meter key or pliers to open it.
Inside the Building: Look for it where the water line enters the building (basement, crawl space, or utility closet).
Exterior Wall: In some climates, it may be located on an exterior wall, protected by insulation or a small enclosure.

Prepare: Ensure you have the necessary tools (meter key, pliers, adjustable wrench).
Open the Meter Box (if applicable): Use a meter key to lift the lid.
Locate the Shut-Off Valve: This will usually be a valve that requires you to turn it.
Turn Off the Water: Turn the valve clockwise to shut off the water supply. A ball valve requires only a quarter turn. A gate valve requires multiple turns.
Test the Shut-Off: Turn on a faucet to confirm the water is completely shut off.

Emergency Situations: Know the location of your main shut-off valve before an emergency occurs (e.g., a burst pipe).
Frozen Pipes: If pipes are frozen, turn off the water before they thaw to prevent leaks when the ice melts.
Valve Condition: Periodically check the valve to ensure it's functioning correctly and hasn't corroded. If it's difficult to turn, consider having it replaced by a plumber.
Neighbors Water: Be aware that turning off the main may effect other residents if you live in an apartment building. Alert them before turning the water off.
After Shut-Off: Before turning the water back on after a repair, check all faucets and appliances that use water. Turn them all off. This prevents water damage should a leak occur while the water is turned off. Then turn the water on slowly to allow air to escape the system.