How to Prevent Frozen Pipes in a Colorado Cold Snap

Why do pipes in Front Range homes freeze?

Water that sits still in a cold pipe turns to ice, and ice takes up more room than the water did. The pipe itself rarely fails right at the frozen plug. Pressure builds in the trapped section between the ice and a closed faucet, and that is where copper splits or a fitting lets go. A house can feel warm in the living room while a line inside an exterior wall, an attached garage or a crawl space drops well below freezing.

Denver Water points out that the same conditions that break its own mains in the street can burst pipes inside homes. Colorado winters bring stretches when temperatures sit far below freezing, as the Ken-Caryl Ranch Water and Sanitation District reminds its customers each season, so the routine below is worth setting up before the first deep cold arrives.

Where are the weak spots in your house?

Walk the house in fall with a flashlight and look for supply lines in these places:

• Exterior walls, especially kitchen and bathroom sinks set against an outside wall.
• Unheated basements and crawl spaces, plus any vents or access doors that let outside air in.
• Attached garages, where builders sometimes run plumbing to a laundry or a bathroom above.
• Hose bibs and the pipe just inside them, which freeze fastest when a hose is left attached.
• Irrigation lines and the backflow assembly on the sprinkler system.

The Columbine Water and Sanitation District also suggests closing up crawl spaces, fixing drafty windows and sealing gaps where cold air reaches pipes, using spray foam or caulk on wall cracks.

What should you do before the first hard freeze?

Find and test the main shutoff

Denver Water says the shutoff in most single-family homes is in the basement or crawl space, on the wall that faces the street. Turn it off and back on once so you know it moves, and show everyone in the house how to close it. A valve you can close in thirty seconds turns a burst pipe from a flood into a puddle. If it is stuck or missing, have a plumber replace it now rather than during an emergency. Denver Water's leak guidance says a home without a main shutoff should have one installed. Some homes also have an outside curb stop, which Columbine's guidance recommends locating as a backup.

Deal with everything outdoors

• Disconnect every garden hose. The Evergreen Metropolitan District lists a hose left on a spigot as one of the clues it checks when a service line freezes.
• If your hose bibs have an indoor isolation valve, close it and open the outdoor spigot to drain it.
• Shut off the sprinkler system and drain or blow it out. If your sprinkler line has a backflow assembly, water left inside it can freeze along with the rest of the system; see how backflow assemblies are tested and serviced in spring.

Insulate the lines you found

Foam pipe sleeves on lines along exterior walls and in unheated basements are the simplest fix, and both Denver Water and Columbine recommend them. For a run that freezes every year, heat tape rated for the pipe material adds protection. Follow the maker's instructions closely for how it is wrapped and covered.

What is the routine on a bitter night?

Denver Water suggests dripping the faucet farthest from where water enters the house, with a bucket underneath so the water can be reused. Columbine notes that the small amount of water usually costs far less than repairing a broken pipe.

What if you are leaving town?

Denver Water advises keeping the thermostat above 65 degrees when you leave home or a business for several days. Columbine's guidance gives a floor of no lower than 55 degrees. Utilities differ on the exact number, so treat 55 as the bare minimum and lean warmer when a cold front is forecast. For a longer trip, close the main valve and open a faucet on the lowest level to drain the lines, and ask a neighbor to check the house if temperatures plunge.

This matters for insurance too. The National Association of Insurance Commissioners says homeowners policies often cover water damage from a frozen pipe if the owner took reasonable steps to prevent it, and that policies generally require keeping the home at a minimum temperature or shutting off the water while it sits vacant. Read your own policy for its exact wording before a trip.

Foothills and mountain homes

Homes in Evergreen, Conifer, Bailey and other foothills communities see longer, colder nights than the city. Evergreen Metropolitan District customers are on district water, while Jefferson County says mountain-area homes are generally supplied by wells. On a private well, the pump, the pressure tank and the line from the wellhead need protection as well; a well pump problem in Conifer after a freeze often turns out to be a frozen pipe near the tank. Evergreen Metro also says that if a frozen section is between the outside shutoff and the house, it is the homeowner's to thaw, while the district handles its side. Readers in the Evergreen area can check that district guidance for details.

How do you thaw a frozen pipe safely?

You will usually notice a frozen line when a faucet gives a trickle or nothing at all while others still run. Work through this in order:

1. Close the main valve first. Denver Water and Columbine both say to shut off the water, or at least test the valve, before thawing, so a hidden split does not start spraying the moment the ice melts.
2. Open the faucet the line feeds. Evergreen Metro stresses opening faucets while thawing so meltwater and pressure have somewhere to go.
3. Add gentle heat. A hair dryer, a heating pad, a space heater warming the room, or towels soaked in hot water all work. Ken-Caryl warns against a torch and notes that thawing too quickly can itself crack the pipe.
4. Restore water slowly. Open the main a little at a time and check the pipe and nearby joints for drips, as Columbine advises.

If the frozen spot is inside a finished wall or ceiling, you cannot see it, or you thaw it and find water seeping out, stop and call for help. A plumber can trace the line and make a repair on the split section before the wall soaks through. If the pipe has already burst, our walkthrough on what to do in the first ten minutes covers shutoffs, electrical safety and cleanup.

When is a permanent fix worth it?

A pipe that freezes every winter is telling you it is in the wrong place. Options include adding insulation inside the wall during other remodeling, sealing the crawl space, moving the line to an interior wall, or swapping a standard spigot for a frost-free style. In older homes with corroded or patched supply lines, replacing the piping lets the new runs be routed through heated space from the start. Before spending money, a leak detection visit can confirm that last winter's freeze did not leave a slow drip behind the drywall.

Whether you are in Aurora, Littleton or Ken Caryl, the steps are the same. If a cold snap is already here and a line has gone quiet, you can reach someone for an Aurora burst pipe repair or a Littleton water line repair through this site. For help deciding how fast to act, see whether a problem needs an emergency call.