Pipe Thawing
The thawing operation itself, methods, safety and why flame is never used.
Learn moreWinter failures
A Frozen Pipe Is a Repair Job. The Flood Comes on the Thaw
Losing water during a cold snap is the symptom everyone recognises. What people miss is that ice does its damage while the pipe is still frozen, and the water only appears when things warm back up. Call before that happens and the job stays small.
Lines are open right now:
(833) 472-2088
Lost water in the cold? Shut the main first, then call.
Found, then fixed
Locating the ice is half the work. Guessing wastes the callout.
No open flame
Torches are how frozen pipes become house fires. Never used here.
Same-day in a cold snap
Freeze weeks are the busiest of the year and slots move fast.
Cause addressed
A pipe that froze once will freeze again unless something changes.
What is actually happening
Why the pipe splits while it is still frozen
Water expands as it turns to ice. In a closed pipe there is nowhere for that expansion to go, so pressure builds ahead of the ice plug, and the failure usually occurs not at the ice itself but somewhere along the trapped section, at the weakest fitting or the thinnest wall. Copper splits along its length. CPVC and PEX behave differently: PEX will often stretch and survive, which is exactly why it is now standard in cold-climate construction, though its brass fittings still crack.
Here is the part that surprises people. That split does not leak while it is frozen, because the ice is plugging it. Everything looks dry, the house is quiet, and there is simply no water at the tap. Then the temperature climbs, the plug melts, and the pipe empties into the building at full pressure, often when nobody is home, because the warmest part of the day is a working afternoon.
So the useful sequence when you lose water in cold weather is: shut off the main, then call. Not the other way around. If the line has already split, closing the valve means the thaw releases a bucket instead of a bathtub.
The tell you can check yourself
Only one fixture is dry and the rest of the house is fine? That is a localised freeze on a branch line. No water anywhere in the building? The freeze is closer to the main, the crawl space, the meter, or the service entry, and the exposure is much larger.
One dry tap or the whole house? Tell us and we'll narrow it down.
The usual suspects
Where pipes freeze in Idaho houses, in order of frequency
Freezes are not random. In a decade of cold snaps, the same handful of locations account for most failures, and knowing them shortens the diagnostic hunt considerably.
Crawl spaces
The single most common location statewide. A vented crawl space is, thermally, outdoors, and the supply lines running through it are frequently uninsulated, badly insulated, or insulated on the wrong side. Add a vent that was never closed in October and a north wind, and you have the classic failure.
Exterior walls and rim joists
A supply line run through an outside wall to serve a kitchen sink or a laundry has only sheathing between it and the weather. The rim joist is worse: cold air tracks along it, and the pipe sits in the coldest cubic foot of the house.
Unheated garages and utility rooms
Very common in newer Treasure Valley subdivisions where the water heater and softener live in the garage. The house stays warm, the garage does not, and the garage holds the equipment.
Hose bibs and sillcocks
The hose that never came off in autumn traps water in the bib, the water freezes, and the split appears inside the wall behind it, discovered the following April when someone turns the tap on to wash a car.
Cabins and second homes
In McCall, Cascade, Donnelly, Idaho City and the Panhandle lake country, an empty house with a failed heat source is the whole ballgame. Nobody notices until a neighbour sees ice on the siding.
The work
Locate, thaw under control, then repair
A frozen-pipe call has three phases, and rushing the first one is what turns a tidy job into an expensive one.
Locate. Which fixtures are dead tells the plumber roughly where the plug is; surface temperature readings, the run of the piping and the geometry of the house narrow it down. Cold spots along a wall, frost on a fitting in the crawl space, or a section that reads twenty degrees below its neighbours all mark the spot.
Thaw under control. Heat is applied gradually, from the fixture end back toward the ice, with the tap open so meltwater and pressure have somewhere to go. Controlled electric heat, warm air and heat tape are the tools. Open flame is never one of them, the fire risk is real, and rapid heating can burst a pipe that would otherwise have survived. Our pipe thawing page covers this stage in detail.
Repair. As the ice releases, the leak reveals itself. The failed section gets cut out and replaced, copper to copper, or a transition to PEX where the run is exposed to cold and it makes sense. Then the system is brought back up under pressure and watched, because the first split is often not the only one.
Where the failure is inside a wall or under a slab, drywall or flooring has to come out. That part is unavoidable, but a good plumber opens the smallest hole that lets the repair be done properly.
Freeze weeks book out fast. Earlier in the day is better.
Documentation
What to photograph before anything gets cleaned up
Frozen-pipe damage is one of the more commonly claimed household losses, and the difference between a smooth claim and an argument is usually documentation taken in the first hour.
Photograph the standing water before you touch it. Photograph the failed section of pipe before it is cut out, and ask the plumber to keep the removed piece, a split length of copper in a bag is persuasive evidence. Photograph the affected rooms wide, then close. Keep the written quote and the invoice, both of which should describe the cause plainly.
One detail worth knowing: policies frequently distinguish between a pipe that froze because of weather and one that froze because heat was not maintained in the building. That distinction matters a great deal for seasonal homes and rentals sitting empty in winter, and it is a good reason to keep records of thermostat settings and any winterization work performed. Coverage questions belong to your insurer, not to us, but the plumbing record we leave behind should support whatever conversation you need to have.
Afterwards
A pipe that froze once will freeze again
The repair fixes the pipe. It does not fix the reason the pipe was cold, and in a place with Idaho's winters that reason will be back within twelve months.
The fixes are usually modest. Sleeve insulation on the run, correctly sized and actually closed at the seam. Crawl space vents dealt with for the season and the hatch sealed. Air sealing at the rim joist, which does more than insulation alone because the problem is moving air rather than conduction. Rerouting a short section out of an exterior wall and into a heated interior chase during the repair, while the wall is already open, by far the cheapest time to do it. Heat tape with a thermostat on the sections that genuinely cannot be moved, installed to the manufacturer's instructions rather than wrapped hopefully around a fitting.
For houses that stand empty part of the year, the answer is a proper drain-down instead: see cabin and seasonal home winterization. And for the annual autumn round of hose bibs, exposed pipe and crawl space work, freeze protection and winterization is the appointment that prevents this page ever becoming relevant to you.
The repair is the moment to fix the cold cause too.
How it runs
From no water to water again
The order matters more in freeze work than in almost any other plumbing call.
Shut the main, then call
Closing the valve before the thaw is the single highest-value thing you can do. Then tell us which fixtures are dry, that alone locates the freeze roughly.
Locate and thaw slowly
The pro narrows the ice down by temperature and pipe run, opens the tap and applies controlled heat from the fixture back toward the plug. No flame, no shortcuts.
Repair and pressure-test
Splits reveal themselves as flow returns. Failed sections are cut out and replaced, the system is repressurised and watched, and the cold cause gets addressed.
Coverage
Freeze work happens everywhere in this state
Eastern Idaho and the mountain valleys see the deepest cold and the longest freeze season; the Treasure Valley sees the highest volume simply because that is where most of the houses are; and the Panhandle adds wet snow and basements to the mix. Every community on this site is covered.
Questions
Frozen pipe questions
Sometimes, if the pipe is exposed, accessible and you can see the whole run. Open the tap first, work from the fixture back toward the frozen section, and keep the heat gentle and moving. Stop immediately if you see or hear water, that means there is a split.
Never use a torch, a propane heater aimed at framing, or a heat gun held on one spot. Open flame near pipes causes structure fires every winter in this state, and sudden localised heating can rupture a pipe that would otherwise have thawed intact.
Usually you don't, until it thaws, which is the whole problem. The signals worth acting on are a section of pipe that is visibly bulged or split, staining on drywall or a ceiling below the run, and any sound of water when there should be none. Because you cannot be sure, the safe assumption is that it might have split: close the main and leave it closed until someone has looked.
A localised freeze on an accessible branch is often flowing again within thirty to sixty minutes of heat being applied. A crawl space main or a buried service line can take several hours, and a frozen line under a slab or behind finished wall can take most of a day. Rushing it with more heat is how pipes get destroyed, so pace is deliberate.
Shut the main immediately, open a low tap to drop the remaining pressure, kill power to any wet area at the breaker if you can safely reach the panel, and call. Take photographs before cleanup. That situation is an emergency call rather than a scheduled repair, see burst pipe repair.
It genuinely helps on vulnerable runs. Moving water freezes more slowly than still water, and an open tap gives expansion somewhere to go, which is the more important effect. A slow drip on the fixture furthest along an exposed run, opening cabinet doors so warm room air reaches the pipes underneath, and keeping the house at a steady temperature rather than setting back at night are all worth doing on the coldest nights.
Below the frost line, generally yes, but the frost line in Idaho is deeper than newcomers expect, and it is deeper again in the eastern part of the state and at elevation. The vulnerable points are where a buried line comes up: the meter pit, the crawl space penetration, the point of entry into an unheated garage. Those transitions are where buried lines actually freeze.
Different system and different work. Irrigation piping sits shallower than your water service and is meant to be empty over winter, which is what an autumn blowout accomplishes. Freeze damage there shows up at valve bodies, manifolds and backflow assemblies. See irrigation system plumbing repair.
Usually, and it is the cheapest possible moment to do it, because the wall or the crawl space is already open. Insulation, air sealing at the rim joist, thermostatic heat tape or rerouting a short run into heated space are all commonly done in the same visit. You will be quoted for it separately so the choice stays yours.
Cold snap coming? Same-day slots go early.
Don't wait for the thaw to find out.
If you have lost water in freezing weather, the main shutoff and this phone number are the two things worth reaching for. Everything after that is a manageable repair.
(833) 472-2088