Guides · Twin Cities homes
How do I keep my pipes from freezing in a Minnesota cold snap?
The short answer
Pipes freeze where they meet cold air: exterior walls, unheated basements, crawlspaces, garages, and the outdoor spigot. Keep them above freezing by insulating exposed runs, opening cabinet doors on exterior walls, leaving a faucet at a trickle on the coldest nights, and keeping the house heated when you travel. Frozen pipes do their damage when they thaw.
Which pipes freeze first
Water doesn't freeze because the house is cold — it freezes because a specific pipe is sitting in air below 32°F. In Twin Cities homes the usual suspects are the kitchen sink on an exterior wall, bathroom supply lines in an outside wall, anything running through an unheated garage or crawlspace, the line to the outdoor spigot, and pipes near a basement rim joist where the insulation stops. Older homes on the older blocks of Minneapolis, St. Paul, and the first-ring suburbs have the most of these.
Before the cold hits
- Disconnect every hose and, if the spigot isn't frost-free, close its inside shutoff and drain it. A hose left on is the number one way a spigot line splits.
- Insulate exposed pipe in the basement, garage, and crawlspace with foam sleeves — cheap, fast, and effective on the pipes you can reach.
- Seal air leaks near pipes: gaps around the rim joist, dryer vents, and where lines pass through exterior walls. Cold air blowing directly on copper is what freezes it.
- Know your main shutoff — usually in the basement near the water meter. If a pipe does burst, this is the valve that stops it.
On the coldest nights (below zero, or wind chill warnings)
- Open the cabinet doors under sinks on exterior walls so warm room air reaches the pipes.
- Let the faucet farthest from the main run at a pencil-thin trickle — moving water freezes far less readily, and it relieves the pressure that actually bursts pipes.
- Keep the thermostat steady. Setback thermostats that drop the house to 55°F overnight are a common cause of frozen exterior-wall lines.
- If you travel, don't turn the heat below about 55°F, and have someone check the house — or shut off the main and drain the lines for a long absence.
If a pipe is already frozen
A faucet that produces nothing, or a trickle, on a cold morning means ice in the line. Leave the tap open — as the ice melts, water needs somewhere to go. Warm the pipe gently and gradually: a hair dryer, a space heater in the room, warm towels. Start at the faucet end and work back toward the frozen section. Never use a torch or open flame on a pipe, and don't try to thaw a pipe you can't see or reach.
The critical thing: ice doesn't burst pipes — thawing does. Water expanding as it freezes can split the pipe, but you won't see a drop until the ice plug melts and the split opens up. If you're thawing a line, be ready at the shutoff.
Try it yourself, or call?
Worth trying first
- Everything in the prevention lists above — it's all homeowner work
- Gentle thawing of a pipe you can see and reach, with the faucet open
Time to call
- The frozen section is inside a wall, ceiling, or somewhere you can't reach
- The pipe has thawed and you see water anywhere — shut the main and call now
- The same pipe freezes every winter — that's a fixable routing or insulation problem, not weather
- You're leaving for the winter and want the system drained properly
Common questions
A pipe burst and water is pouring out. What do I do first?
Shut off the main water valve — basement, near the meter, usually — then call us. Then kill the power to any area where water is near outlets or appliances. Don't worry about the mess yet; stopping the water is the whole job in the first sixty seconds.
Does letting a faucet drip really work?
Yes, for two reasons: moving water is harder to freeze, and an open tap relieves the pressure that builds between an ice plug and the closed faucet — which is the pressure that actually splits pipes. A trickle on the coldest three or four nights of the year costs almost nothing.
My outdoor spigot is frost-free. Do I still need to disconnect the hose?
Yes — that's the one thing that defeats a frost-free spigot. With a hose attached, water can't drain out of the long stem, it freezes, and the pipe splits inside the wall. You find out in April. Disconnect the hose; that's the entire winterizing routine.