Guides · 2026-10-25 · By David Linda, Founder

Frozen or burst pipes in Colorado: what to do first and how to check an emergency plumber

If a pipe just burst: shut off the water at the main valve (in most single-family homes it's in the basement or crawl space, on the wall facing the street). If that valve won't turn, a plumber or your water utility can shut the water off at the curb. Stay away from water near outlets or the electrical panel. Photograph everything, stop further damage, and call your insurer before you make permanent repairs. Then hire a plumber with an active Colorado state license, which you can check on DORA's lookup, and ask them for their verified HomeProFax report.

Colorado winters swing hard. A sunny 50-degree afternoon can turn into a subzero night, and that's when pipes in exterior walls, crawl spaces and attached garages freeze. Unlike roofers and general contractors, plumbers in Colorado hold a state license, so checking the person you call in an emergency is easier than you might think. This guide covers how to prevent a freeze, what to do in the first hour after a pipe bursts, how insurance treats water damage, and how to check a plumber quickly, with what HomeProFax's state license data shows in the biggest Front Range cities.

How cold it gets, and when

The National Weather Service office in Boulder keeps Denver's long-term records. According to its fall, winter and spring statistics:

Denver's average first freeze is October 7 and its average last freeze is May 5. That's about seven months of the year when a cold night is possible. This year's first freeze came on October 16, 2026.
The freeze has come as early as September 8 (in 1962 and 2020) and as late as June 8 (2007).
Denver's record low is −29°F (January 9, 1875). More recently it hit −24°F on December 22, 2022.
The longest stretch at or below 0°F was 115 consecutive hours, December 21 to 25, 1983.
Big swings are normal. The temperature fell 75 degrees over two days ending December 22, 2022, from 51°F to −24°F.

That last point is the one that catches people. A house that coped fine with a mild December can lose a pipe in one arctic night, especially if the cold arrives with wind, or while you're away.

Before a deep freeze: what Denver Water recommends

Denver Water and its TAP article on frozen pipes give the same practical list. None of it needs a contractor.

Find your shut-off valve now and test it. In most single-family homes it's in the basement or crawl space, on a wall facing the street. Make sure everyone in the house knows where it is and how to close it.
Keep the meter pit and curb stop accessible. If the inside valve won't work, a plumber or Denver Water may need to shut the water off at the curb valve near the street. Denver Water says many curb valves can't be operated because they've seized or the valve box is full of debris, so check that yours is clear.
Drain sprinklers and outdoor faucets before the first freeze. Shut off the indoor valve that feeds the outside faucet, open the outside tap to drain it, and disconnect the hose so a freeze-proof faucet can drain.
Insulate vulnerable pipes along exterior walls, near windows and in unheated basements. For hard cases, ask a professional about heat tape, and never put heat tape on the water meter.
Protect an indoor water meter. Denver Water warns that a frozen meter can flood a basement, and it will replace the meter at your cost before your water is restored.
Winterize vacant or unheated buildings. A burst pipe in an empty house can run for days before anyone notices.

During a cold snap

Open cabinet doors under sinks on exterior walls so house air can reach the pipes.
Keep an attached garage's doors shut. Plumbing is sometimes routed through that unheated space.
Let a very slow drip run from the faucet farthest from where water enters the house, with a bucket under it to save the water.
Leaving for several days? Denver Water says to keep the thermostat above 65 degrees.
After a big snow, clear the outside vents for the furnace, water heater, dryer and fireplace. The Colorado Division of Insurance warns that snow-blocked vents can trap carbon monoxide inside. (Our furnace and HVAC guide covers carbon monoxide alarms.)

If a pipe is frozen but hasn't burst

Denver Water's advice is not to wait for nature to take its course. Thaw the pipe as soon as possible or call a plumber. If you do it yourself, shut off the water first, or at least test the shut-off valve, so water doesn't gush out when the ice lets go. Warm the pipe slowly. A hair dryer aimed at the frozen section is appropriate. A blowtorch is not, and pipes warmed too fast can break.

If a pipe bursts: the first hour

Shut off the water. Main valve first. If it won't turn, call a plumber or your water utility to close the curb valve. Denver Water's emergency line is 303-628-6801. Some cities will do it for you: Westminster, for example, says city staff can shut water off at the meter pit on request. Look up your own utility's number today and save it in your phone.
Mind the electricity. If water is near outlets, appliances or the electrical panel, stay out of the water and call an electrician or the utility before you touch anything.
Document before you clean. Photos and video of the leak, the water line on walls, the floors and every damaged item.
Stop the spread. Move belongings, mop and run fans. The Division of Insurance says you need to mitigate further damage, but should get instructions from your insurer before you make repairs.
Call your insurer. Get a claim number and ask what they need from you.
Call a licensed plumber to repair the pipe, and keep the invoice and the damaged section of pipe if the plumber can save it.

What homeowners insurance usually covers

The Colorado Division of Insurance says burst pipes, and the water damage they cause to the home (such as floors and cabinets) and its contents, generally are covered under homeowners and renters policies. Its other points are worth knowing before you call:

Additional Living Expenses. If water damage from a covered loss makes your home uninhabitable, you may be able to claim the extra cost of a hotel or other housing. Keep receipts.
Food spoilage. After an extended power outage you may be able to claim spoiled food.
Send an inventory with the claim. DOI says claims often get delayed when the homeowner leaves out an inventory of damaged property, and that sending information in bits and pieces slows things down.
What's usually not covered. DOI's page on what homeowners insurance doesn’t cover says water damage from an interior broken pipe may be covered, but flooding from rain water and breaks in outdoor water systems, such as sprinklers and irrigation lines, are typically excluded. Flood requires a separate policy through the National Flood Insurance Program, and DOI lists sewer backup among the coverages you may need to buy separately. Check your policy's water damage exclusions.

If your claim stalls or you're concerned about what you're hearing from the company, call DOI Consumer Services at 303-894-7490 (800-930-3745 outside the Denver metro area).

Who licenses plumbers in Colorado

Plumbing is one of the few home trades on Colorado's list of state-licensed occupations, alongside electrical work. The DORA Division of Professions and Occupations licenses apprentice, journeyworker, master and residential plumbers, and registers plumbing contractors, through the State Plumbing Board. The Board was established in 1917 and has been part of DORA since 1970.

The company should hold a plumbing contractor registration.
The person doing the work should hold their own license. A residential plumber license is limited to residential work.
Permits. DORA's permit page says a plumbing contractor must pull permits for its own work, not use a homeowner permit or another company's. The state adopts the International Plumbing Code, International Residential Code and International Fuel Gas Code, and state inspectors cover areas without a local program (27 counties, per DORA). Cities such as Denver run their own permits and inspections.
Gas lines. Colorado's plumbing law defines gas piping and has the Plumbing Board adopt a Colorado Fuel Gas Code for inspecting fuel gas pipe installations (C.R.S. 12-155-103). Cities also license gas work, so ask who will pull the permit.
Renewals. Plumbing licenses run on a two-year cycle with a license year from March 1 to February 28, and active plumbers need 8 hours of continuing education each year, according to the Board.

Most cities also want a state-licensed plumber registered locally. Aurora, for example, requires a current Colorado master's and contractor's license on file and doesn't issue a separate plumbing license. Our guide to hiring an electrician or plumber in Colorado covers license types and renewal dates in more detail.

How to check a plumber in five minutes

Ask for the company's plumbing contractor registration and the name and license number of the master plumber behind it.
Look both up on DORA’s license lookup. Check that the status is active and look at the expiration date. In our data, nearly all active plumbing licenses show a February 28, 2027 expiry.
Look for discipline. DORA publishes board actions, and HomeProFax shows a flag on the profile with a link to the source.
Ask whether the repair needs a permit, and confirm it will be pulled in the company's name.
Get the price in writing before work starts, even in an emergency. A text or email counts.

Or skip the lookups and ask the plumber for their verified HomeProFax report. It puts the state license records, expiry dates, any board-action flag and matched permits on one page.

What HomeProFax's data shows in Front Range cities

HomeProFax builds its Colorado plumbing profiles from the State Plumbing Board roster. Here's how many plumbing contractor registrations sit on profiles with an address in each city, and how many of those are active. A plumber based in one city can work across the metro, so this is a rough picture of where companies are based, not a count of who serves you.

City (profile address)	Plumbing contractor registrations	Active	Plumbing-license profiles with a discipline flag
Denver	436	251	66
Colorado Springs	430	272	73
Aurora	265	176	43
Littleton	141	67	32
Arvada	140	74	24
Lakewood	121	64	16
Fort Collins	115	61	31
Thornton	102	57	22
Pueblo	89	55	14
Westminster	82	49	15
Boulder	55	29	6

Two things stand out. First, in most of these cities roughly half to two-thirds of the contractor registrations on file are active, because the state roster keeps expired records. A license number alone proves nothing until you see its status. Second, a discipline flag can mean anything from a paperwork fine to a revocation, so read the record and its date before you decide. It's a reason to ask, not a verdict.

Browse plumbers by city: Denver · Colorado Springs · Aurora · Lakewood · Arvada · Thornton · Boulder · Fort Collins.

Emergency red flags

No license number, or only a city business license. Plumbing needs a state license.
"We'll do it on your permit." DORA says a contractor must pull its own permits.
Large cash payment before any work, or a price that changes once the water is off. Agree the price in writing first.
Pressure to replace everything right now. Stop the leak and dry the house first. Larger repiping can wait for a second quote and the adjuster.
Steering you away from your insurer. Call your insurer yourself. DOI says to get its instructions before you make repairs.

If something goes wrong

For a complaint about a licensed plumber, use the State Plumbing Board's complaint process on the Board’s page. For insurance problems, call DOI at 303-894-7490. If a contractor took your money and didn't do the work, the Attorney General's complaint page recommends a theft report with local police, and you can file a consumer complaint at StopFraudColorado.gov (800-222-4444). Our guide A contractor took my deposit in Colorado covers demand letters and small claims, which handles cases up to $7,500.

Last updated October 25, 2026. Weather records: National Weather Service Denver/Boulder. Prevention steps: Denver Water and the City of Westminster. Insurance guidance: Colorado Division of Insurance. Licensing and permits: DORA Division of Professions and Occupations and C.R.S. 12-155-103, checked October 25, 2026. Plumbing figures: HomeProFax profiles built from the DORA State Plumbing Board roster, counted by the city on the profile address, as of October 24, 2026. The discipline column counts profiles that hold any Colorado plumbing license and carry a board-action flag. This is general information, not legal, insurance or plumbing advice. In an emergency involving gas, electricity or injury, call 911.

Common questions

What should I do first if a pipe bursts?

Shut off the water at the main valve. In most single-family homes it’s in the basement or crawl space on the wall facing the street. If it won’t turn, a plumber or your water utility can close the curb valve; Denver Water’s emergency line is 303-628-6801. Then stay clear of water near electrical outlets, document the damage, and call your insurer.

How do I thaw a frozen pipe safely?

Denver Water says to thaw it as soon as possible or call a plumber. Shut off or test the shut-off valve first, then warm the pipe slowly, for example with a hair dryer. Never use a blowtorch, and remember that pipes warmed too fast can break.

Does homeowners insurance cover burst pipes in Colorado?

The Colorado Division of Insurance says burst pipes and the resulting water damage to the home and its contents are generally covered under homeowners and renters policies. Breaks in outdoor water systems such as sprinklers, and flooding from rain, are typically excluded. Check your policy’s water damage exclusions.

Do plumbers need a license in Colorado?

Yes. Plumbing is licensed by the state through the DORA State Plumbing Board, which licenses apprentice, journeyworker, master and residential plumbers and registers plumbing contractors. You can check any plumber on DORA’s online license lookup.

Who should pull the permit for a plumbing repair?

The plumbing contractor. DORA says a plumbing contractor must pull permits for its own work rather than use a homeowner permit or another company’s permit.

What temperature should I leave my house at when I travel in winter?

Denver Water recommends keeping the thermostat above 65 degrees while you’re away for several days, and shutting off and draining outdoor faucets before the first freeze.

When does Denver’s freeze season start?

According to the National Weather Service, Denver’s average first freeze is October 7 and its average last freeze is May 5. In 2026 the first freeze came on October 16.

Sources

Official pages we checked for this guide. Rules change, so confirm with the agency before you rely on them.

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