Every January cold snap, my phone fills up with the same call: no water at one faucet, then a thaw, then water where it shouldn't be. A burst pipe is one of the most expensive things that can happen to a house — and it's almost always preventable.
After years of chasing frozen lines around Billings, Laurel, and Red Lodge, I can tell you they freeze in predictable places for predictable reasons. Fix those, and you can stop worrying every time the forecast shows twenty below.
Where pipes actually freeze
Water doesn't freeze because your house is cold — it freezes because a specific section of pipe sits in a spot that gets cold. The usual suspects around here:
- Pipes in exterior walls, especially kitchen sinks on north-facing walls
- Lines running through unheated crawl spaces, garages, and rim joists
- Hose bibs that weren't drained, and the pipe just inside the wall behind them
- Under-insulated additions, bonus rooms over garages, and mobile home skirting
- Well lines and pressure tanks in unheated pump houses
What actually works (and what doesn't)
Pipe insulation alone is the most misunderstood fix. Foam sleeves slow heat loss — they don't create heat. A pipe in a space that sits below freezing for days will still freeze, insulated or not. Insulation works when it keeps a pipe on the warm side of the line; it fails when the whole cavity goes cold.
The fixes that hold up in real Montana winters: getting heat to the space (even a little), heat tape installed correctly on vulnerable runs, air-sealing the drafts that blast cold air across a pipe, and — the permanent fix — rerouting the line out of the cold spot entirely. When I open a wall to fix a burst, rerouting is almost always what I recommend so we're not meeting again next winter.
The cold-snap routine
When the forecast drops below zero for a stretch, a few habits dramatically cut your risk:
- Open cabinet doors under sinks on exterior walls so room heat reaches the pipes
- Let the most vulnerable faucet run at a pencil-lead trickle overnight — moving water resists freezing
- Keep the furnace at a steady temperature day and night; big setbacks let wall cavities go cold
- Disconnect garden hoses and make sure hose bibs are drained or frost-free
- If you leave town, keep heat at 55°F minimum and have someone check the house
If a pipe freezes anyway
No water at one fixture during a cold snap almost always means ice somewhere in the line. Shut off the water to that section (or the whole house) before you thaw anything — the danger isn't the ice, it's the split the ice may have already made, which only leaks once things melt.
Gentle heat works: a hair dryer, a space heater in the room, warmth from opened cabinets. Never use a torch or open flame on a pipe. And if you can't find the frozen section, or you see a bulge or a split, stop and call — thawing a burst pipe without the water off turns an inconvenience into a flooded floor.
Cabins, vacation homes, and long trips
A house that sits empty in winter plays by different rules. If a cabin near Red Lodge or a rental between tenants won't be heated, the safest move is a full drain-down: shut off the main, open every faucet high and low to drain the lines, flush the toilets dry, and pour RV antifreeze into every trap — sinks, tubs, toilets, floor drains — so the water sitting in those bends can't freeze and crack the fixtures.
If the house stays heated while you're gone, two cheap layers of protection earn their keep: shut off the main water valve on your way out (a burst pipe with the main off leaks a few gallons, not a few thousand), and put a freeze alarm or smart leak sensor where it can warn your phone if the furnace quits. Every winter I get a call from someone whose furnace failed on day two of a two-week trip — the ones with the water shut off get a repair bill; the ones without get a restoration crew.
Fix it for good
If the same pipe freezes every winter, that's not bad luck — it's a routing problem, and it has a permanent fix. Rerouting a vulnerable line, insulating and air-sealing the cavity, or adding heat tape with a thermostat usually costs a fraction of one burst-pipe cleanup.
This matters double for older homes, where original galvanized or thin-wall copper lines run through spaces nobody would route them today — if that's your house, it's worth reading when it's time to repipe an older home. Our plumber handles freeze-proofing and rerouting across Billings, Red Lodge, and the colder corners of the valley — estimates are free.
THE TAKEAWAY
Pipes freeze in predictable places — exterior walls, crawl spaces, and unheated corners. Insulation slows freezing but doesn't stop it; heat, air-sealing, and rerouting do. If the same line freezes every year, fix it permanently before it bursts.