Winter plumbing checklist for Westminster, CO homes

November 5, 2026 · 5 min read · By Westminster Plumbing Experts

Why pipes freeze in a Westminster winter

Water expands as it freezes. In a pipe, that pressure can crack the pipe or split a fitting, and the damage often stays hidden until the ice melts and the water starts to flow. The pipes at greatest risk are the ones the heat does not reach: outdoor faucets and irrigation lines, pipes in garages, crawl spaces, attics and unheated basements, and pipes in exterior walls.

Nearby Broomfield's water department says pipes can freeze at 20 degrees Fahrenheit or lower, and Arvada's page names hose bibs, unheated basements and garages, and exterior walls as the places at risk. Westminster's own page on frozen pipes and leaks gives the steps below.

A split pipe often does not leak until the ice melts. That is why a crack hidden inside a wall can do more damage than a visible drip: the water starts to flow after the cold has passed, sometimes while no one is looking. Preventing the freeze is far easier than repairing the water damage that follows it.

Before the first hard freeze

Work through this list on a mild autumn weekend. None of it needs special tools.

• Drain outdoor faucets and irrigation. The city asks residents to drain outdoor faucets and irrigation lines before winter. Disconnect and store garden hoses first.
• Insulate exposed pipes. Pipes in garages, crawl spaces, attics and basements are the usual candidates. Insulation slows heat loss; it does not make pipes freeze-proof.
• Find your main shut-off valve and mark it. Westminster's page says to know where the main shut-off valve is inside the home and to mark it. Make sure everyone in the household knows.
• Check that the valve turns. A valve that sticks or leaks is a reason to call a plumber before winter, not during a leak.
• Leave the meter pit lid in place. The city's page says to keep the lid on the meter pit. The pit is on the city's side, so do not open it.
• Seal drafts near pipes. Gaps around pipes that run through exterior walls let cold air reach them.

Where to look, room by room

• Garage. Water lines that run along walls or ceilings are exposed to the coldest air in the house, especially near the garage door.
• Crawl space, attic and unheated basement. Pipes here get little or no heat from the house. Insulation helps, and so does sealing the gaps that let cold air in.
• Kitchen and bathroom on an exterior wall. The pipes behind the sink sit against the cold side of the wall.
• Outside. Hose bibs, irrigation lines and any pipe that runs outdoors. Drain and shut them off before winter.
• The meter and main. Know where the valve is, check that it turns and keep the meter pit lid in place.

When you are away or the temperature plunges

Keep the heat on when you travel. Broomfield and Arvada both advise keeping the thermostat at 55 degrees Fahrenheit or higher, even when no one is home. On the coldest nights, opening cabinet doors under sinks on exterior walls lets warm air reach the pipes. A neighbor or friend who can check the house if the power goes out is worth arranging before you leave.

If a faucet on an exterior wall stops running or only trickles on a freezing morning, the pipe may be frozen. The city advises thawing slowly, for example with a hair dryer, and never with a blowtorch. If you cannot find the frozen section, or you see a split, wet drywall or a drip, shut off the main valve and call a plumber.

Who handles what if something goes wrong

Westminster's pages draw a clear line. The city's responsibility ends at the water meter, and the pipe and fittings on your side of the meter belong to the owner. If water is coming up in the yard near the meter, or the meter pit itself is leaking, call the city. A leak inside the house or between the meter and the house is a plumber's call.

If your own shut-off valve will not close during an emergency, the city can shut off the water at the meter pit on request. That is worth knowing before the cold arrives. The same principle holds across nearby cities, but the exact boundaries differ, so see our service area guides for the place you live.

When to call a plumber

A checklist reduces the odds of a problem but cannot eliminate them. Call when:

• Water is flowing from a pipe, wall or ceiling. Close the main valve first, then follow emergency plumbing.
• A pipe will not thaw, or you cannot tell where it is frozen.
• Your shut-off valve will not close, or it leaks when you turn it.
• Pressure drops after a cold night, which can point to a hidden leak. See plumbing repair.