If you have a plumbing emergency, or if you decide to do some plumbing maintenance yourself, knowing how to shut off the water supply can be critical to a successful outcome.
Main Water Shutoff Valve
All water that is piped into your home from an outside source arrives at what is known as the main shutoff valve. The shutoff valve is generally located in the basement or on an exterior wall in the utility area of your home and is the valve that is used to shut off the supply of water into your house. Find it and clearly label it so that other members of your household can easily identify it. Then see if you can turn the valve off. (Most shutoff valves require a turn to the right to stop the flow of water.)
Main shutoff valves are normally one of two types:
- Gate valve — As the name suggests, a gate valve utilizes an internal gate that moves up and down a stem. The stem is connected to a handle which screws the gate up or down, opening and closing the gate.While this kind of valve is long lasting, it can freeze up if it isn’t used occasionally. It needs periodic checking and turning to ensure that it will open and close easily.
- Ball valve — A ball valve utilizes a sphere with a hole in it to control flow. When the handle is parallel to the pipe, the hole is open for water to flow. When the handle is turned a 1/4 turn (i.e., is at a right angle to the pipe), the sphere is also turned. The hole becomes perpendicular to the valve and the flow of water is stopped.Ball valves can almost always be operated after years of disuse and don’t typically freeze in position.
Gate valves are commonly found in older construction. Newer houses or plumbing with copper or plastic main water pipes generally use ball valves instead. If an opportunity arises to replace your existing gate-style shutoff valve, consider switching to the more reliable and easier-to-use ball valve.
Auxiliary Water Shutoff Valves
Water flows through the main shutoff valve to the pipes that supply various plumbing mechanisms in your home. Typically, the major water pipes (your exterior faucets, your washing machine, your kitchen sink and dishwasher, and your bathroom plumbing) feature an auxiliary shutoff valve, which means you can stop the flow of water to individual fixtures or specific areas of your house during a repair or emergency and still supply water to the rest of your home. Again, find these valves and label them. Auxiliary shutoff valves are generally located close to the fixture that the water pipe serves—under your sinks, beneath your toilet tanks, and near your washing machine.
First, don’t wait for an emergency or a needed repair: Take a few minutes to test all your shutoff valves to make sure that they are not frozen in the open position. If they are frozen, don’t exert extreme force to try to open them. It may be time to call your plumber.
Keep these tips in mind:
- Be sure to turn the valves off and on once or twice a year, especially if your main shutoff is a gate valve. This simple preventative step will ensure the valves work freely when you need to cut off the supply of water into your home.
- When you’ve closed and then opened a gate-style shutoff valve, it may start to leak a bit around the valve stem. The stem of the valve is held in place with a packing nut. Tighten this nut just enough to stop the leak. Don’t over tighten it or the valve may become difficult to turn.
- Any time you shut off the water and allow the pipes to drain, unscrew the aerators (small screens) on the ends of any affected faucets before you turn the water back on. You will prevent loosened particles of scale from clogging the aerators.
Gate Valve Image: By Heather Smith (The Alloy Valve Stockist’s photo gallery.) [CC BY 3.0], via Wikimedia Commons
Ball Valve Image: By Bitjungle (Own work) [CC BY-SA 4.0], via Wikimedia Commons