Locating Your Main Water Valve

Where to look

Look for the main valve at the spot the supply pipe comes through the foundation, a short reach from the meter. In most Milton homes with basements, that means a wall on the street side, low down, often near the furnace room or under the basement stairs. In townhouses it may be in a utility closet. In slab-on-grade or crawl space homes, try the utility room or any small hatch in the wall.

• Follow the line from the meter: the valve tends to sit on one side of it or the other.
• Look behind removable panels in finished basements.
• Check under the stairs and inside closets near the front of the house.
• Rural homes on wells: the shut-off is typically near the pressure tank.

Types of valve

Ball valve: a lever handle that turns a quarter turn. In line with the pipe means open; across the pipe means closed. Gate or globe valve: a round wheel handle that turns several times. Clockwise to close. Older valves of this type can seize or snap if forced.

Test it gently

Close the valve with a slow, steady hand, then run an upstairs tap to prove the flow has stopped. Turn it back on slowly to avoid a pressure surge. A wheel that refuses to move should not meet a wrench; a snapped stem with the water on is a worse problem than a stiff one. A valve that will not close fully should be swapped on a calm weekday, not mid-flood.

Other valves worth knowing

• The cold valve feeding the water heater.
• Small stops tucked under sinks and behind toilets.
• The inside valves for outdoor taps.
• The washer valves in the laundry.

When to call us

If you cannot find the main, if it is buried behind a finished wall, or if it is stiff, leaking at the stem or will not close, ring us. A quarter-turn replacement is quick work that earns its keep the first time something goes wrong. In winter, when frozen pipes and splits are most common, it matters even more.