Burst and frozen pipes in Boise
Close the main water shutoff, open a low faucet to drain pressure, and turn off power to any wet area from a dry spot. If a pipe is frozen but not broken, warm it gently with a hair dryer or heating pad with the faucet open, never with an open flame. Once water has escaped, get it extracted and drying started within a day or two to limit mold.
Water Damage Boise is an independent guide, not a restoration company. Requests go to a local restoration partner. Last reviewed 2026-11-09.
What happens next, step by step
- 1
Shut off the main water valve
Close the main shutoff right away, then open a faucet on the lowest floor to drain pressure. If you cannot find the valve, many Boise-area homes have one in the basement, crawl space, garage, or a curb box near the street; your water provider can help locate it.
- 2
Kill power to wet areas
If water is running near outlets, light fixtures, or the panel, switch off those circuits from a dry spot, or stay out of the area and call for help.
- 3
Find the break and check for others
Look where pipes run through exterior walls, under sinks on outside walls, in crawl spaces, and near hose bibs. The Red Cross notes that if one pipe freezes, others may too, so check every faucet.
- 4
Photograph everything
Capture the split pipe, the water, and the damaged finishes before cleanup. Save the broken section of pipe if a plumber removes it; adjusters sometimes ask to see it.
- 5
Plumbing repair
A licensed plumber repairs or replaces the damaged section and may suggest insulation, heat cable, or rerouting for pipes in cold spaces.
- 6
Extraction and drying
Restoration crews remove standing water, open wet wall cavities where needed, and run dehumidifiers and air movers until moisture readings return to normal. Water from a clean supply line can turn into a bigger problem if it sits, so drying should not wait for the plumber’s final bill.
- 7
Rebuild and prevent the next one
After drying, drywall, insulation, and flooring are replaced. This is the moment to insulate the run that froze and to add a shutoff or leak sensor if you leave the house in winter.
Why pipes freeze and burst in Boise homes
Water expands as it freezes, and the Red Cross points out that this expansion can break metal or plastic pipe no matter how strong it is. In the Treasure Valley, a few local patterns make that more likely.
Freeze-thaw swings
Boise winters are often mild by day and below freezing at night. Repeated freeze-thaw cycles stress pipes in marginal spaces, and an occasional Arctic cold snap that lasts several days is when most bursts happen.
Crawl spaces and unheated basements
Pipes in crawl spaces, unfinished basements, attics, and garages are on the Red Cross list of lines that freeze most often. Many older Boise homes and some Garden City properties have supply lines running through vented crawl spaces where a broken foundation vent cover or missing insulation lets cold air in.
Older North End and Bench plumbing
Older houses in the North End, East End, and on the Bench may have galvanized steel supply pipe, uninsulated exterior walls, and kitchen sinks on outside walls. Corroded pipe gives way more easily under ice pressure, and renovations sometimes leave a run of old pipe behind a new wall.
Irrigation, sprinkler, and hose bib lines
Outdoor hose bibs and sprinkler supply lines are exposed to the coldest air. The Red Cross recommends draining sprinkler supply lines, disconnecting hoses, closing the inside valve to each hose bib, and leaving the outside tap open to drain. Treasure Valley homes on pressurized irrigation should also follow their system’s winter shutoff instructions.
Warning signs
- Only a trickle from a faucet on a cold morning
- Frost or a bulge on an exposed pipe
- A hissing sound in a wall or the sound of running water when nothing is on
- A jump in your water bill or a water meter that spins with every fixture off
- Wet drywall, a ceiling stain, or water at the base of an exterior wall after a cold night
Prevention that actually helps (from the Red Cross)
- Keep the thermostat at the same temperature day and night during cold snaps.
- If you travel, leave the heat on at no lower than 55°F.
- Open kitchen and bathroom cabinet doors on exterior walls.
- Let a cold tap drip on pipes that are exposed.
- Add insulation to crawl spaces, attics, and basements, and sleeve or heat-cable exposed pipe.
Cost factors for burst pipe damage
A burst pipe usually involves two bills: the plumbing repair and the water damage mitigation and rebuild. We have not found a sourced Boise-specific price for either, so these are national figures.
- Water damage restoration overall: Angi’s 2026 national guide lists a typical range of $1,385 to $6,381 (overall $450 to $16,000).
- Plumbing-related repairs: the same guide lists plumbing repairs tied to water damage at roughly $350 to $4,000.
- Clean water mitigation: supply-line water is usually Category 1 (clean), which Angi averages at about $3.50 per square foot. Water that sits, or runs through dirty materials, can be reclassified to a higher category, which costs more.
- Boise-area pricing: Angi’s city table lists Boise well above the national average (see the cost guide).
What changes the total
- How long the water ran before shutoff (a burst while you are away is the expensive case)
- Which floor: water from an upstairs bathroom travels down through ceilings and walls
- Whether walls must be opened to dry or reach the pipe
- Flooring type: carpet pad usually comes out; some hardwood can be dried in place
- Whether mold has started (EPA: drying within 24 to 48 hours usually prevents it)
Frequently asked questions
How do I know a pipe is frozen before it bursts?
The American Red Cross says that if you turn on a faucet and only a trickle comes out, suspect a frozen pipe. Frost on an exposed pipe, a bulge, or a faucet that suddenly stops on a very cold morning are other clues. Keep the faucet open while you warm the pipe so melting water can flow.
Is it safe to thaw a frozen pipe myself?
Gentle heat is the safe approach: an electric heating pad, a hair dryer, a space heater kept away from anything flammable, or towels soaked in hot water. The Red Cross warns never to use a blowtorch, kerosene or propane heater, charcoal stove, or any open flame. If you cannot find or reach the frozen section, call a licensed plumber.
Why did the leak start hours after the cold snap ended?
Ice inside a pipe can hold back water even after it has split the pipe wall. When the ice melts and pressure returns, water pours out of the crack. That is why many burst pipes are discovered on the first warmer afternoon, or when someone comes home from a trip.
Does homeowners insurance cover a burst frozen pipe in Idaho?
Many homeowners policies list freezing of a plumbing system as a covered peril, according to the Insurance Information Institute, but policies commonly require that you took reasonable care to keep the home heated or the water shut off and drained. Check your own policy and call your insurer; see our Idaho insurance claims guide.
Do I need a plumber, a restoration company, or both?
Usually both. A plumber repairs the pipe; a restoration company extracts the water, measures moisture, and dries the structure. Some companies do both. Make sure the pipe is fixed before rebuild work closes up the walls.
Related guides
- Emergency water removalStanding water, active leaks, and the first 24–48 hours of drying.
- Ceiling water damageStains, sagging drywall, and finding the leak above.
- Insurance claims in IdahoHow homeowners policies typically treat water damage.
- Water damage in Boise: start hereThe overview of every guide on this site.
Talk to a local restoration partner
When you are ready, you can ask a local restoration partner to look at the damage and explain your options. There is no obligation, and you can still get other quotes.