How to Prevent Frozen Pipes in a Missouri Winter

Why Missouri winters are hard on pipes

St. Louis winters swing. A mild week can be followed by an arctic blast that drops temperatures into the single digits overnight, often with wind. Those sudden drops are exactly when pipes freeze, because homeowners haven't prepared and pipes in exposed spots cool faster than the rest of the house.

When water freezes it expands. The ice itself usually isn't what splits the pipe — it's the pressure that builds between the ice blockage and a closed faucet. That's why burst pipes often show up when things thaw: the crack was there, but the ice was holding the water back.

Find the pipes most at risk

Walk your home before the first hard freeze and look for these trouble spots:

• Outdoor hose bibs and spigots, especially older models that aren't frost-free.
• Pipes in crawl spaces, garages and unheated porches.
• Supply lines on exterior walls, particularly under kitchen and bathroom sinks.
• Pipes near basement rim joists, sill plates or foundation vents where cold air leaks in.
• Lines running through attics or above unheated rooms.
• Irrigation and sprinkler supply lines.

Before winter: a simple prevention checklist

During a deep freeze

When the forecast calls for single digits or below-zero wind chills, take a few extra steps:

• Let a thin, steady trickle of water run from faucets on exterior walls, both hot and cold. Moving water is much harder to freeze, and an open tap relieves pressure.
• Open sink cabinet doors on outside walls so warm air reaches the pipes.
• Keep the thermostat steady day and night rather than turning it way down.
• Keep the garage door closed if water lines run through it.
• If you're traveling, leave the heat on — commonly no lower than the mid-50s — and ask someone to check the house.

If a pipe is already frozen

Signs of a frozen pipe include a faucet that produces only a trickle or nothing at all, frost on an exposed pipe, or a bulge in the line.

If a pipe bursts

Shut off the main water supply immediately, turn off the water heater if the leak is large, and move valuables away from the water. Take photos for insurance before cleanup if you can safely do so. Then call for emergency service. City & County Plumbing and Drain answers burst pipe calls 24/7 at (636) 243-8881 — we'll repair the damaged section and look over nearby pipes so the next cold snap doesn't do the same thing.