Do the simple plumbing protections first while you still have heat and running water. The most important preparation is also knowing the main shutoff location before a split pipe forces you to find it under pressure.
The first 10 minutes: protect exposed plumbing
| Trigger | House task | Reason to schedule it |
|---|---|---|
| Minute 0–5 | Confirm heat is running and set a safe temperature; do not use unsafe combustion heaters | A functioning heating system is the primary protection. |
| Minute 5–10 | Disconnect hoses and drain vulnerable exterior faucets if your setup permits | Attached hoses can trap water. |
| Minute 10–15 | Open cabinets below sinks on exterior walls and move chemicals away from children/pets | Room air can reach vulnerable pipes. |
| Minute 15–20 | Use a small drip on known vulnerable lines when local guidance supports it | Moving water can reduce freeze risk in specific situations. |
| Minute 20–25 | Close garage doors and inspect exposed pipes in garage/crawlspace | These spaces can fall below indoor temperature. |
| Minute 25–30 | Locate main shutoff, stage a flashlight, and set a morning inspection reminder | Fast shutoff limits damage if a pipe splits. |
What to do if a pipe freezes or bursts
- Water flow drops sharply at one fixture.
- Frost appears on exposed plumbing.
- Heat stops during the freeze.
- Bulging or cracked pipe is visible.
If you only have 30 minutes, prioritize water control
Start by disconnecting exterior hoses and using any interior shutoff/drain arrangement that is designed for your outdoor fixtures. Open sink cabinet doors where plumbing sits on exterior walls so room heat can reach pipes, and keep the house heated. In especially vulnerable locations, a small trickle at a fixture may be appropriate when local utility or emergency guidance recommends it, but it is not a substitute for fixing chronic freeze exposure.
Know the main water shutoff before going to bed. If a pipe freezes, do not use an open flame, torch or unattended high-heat device to thaw it. If a pipe bursts, shut off water and protect electrical safety before cleanup. After temperatures rise, inspect ceilings, walls, crawlspaces, garages and cabinets near vulnerable runs because a split may reveal itself only after thawing and repressurization.
- Keep garage doors closed if plumbing runs through the garage envelope.
- Do not block furnace or appliance combustion-air and exhaust openings while trying to keep out cold.
- If you will be away, use a caretaker, monitored temperature/leak sensor or another reliable check rather than assuming heat will stay on.
Rank the plumbing by exposure instead of treating the whole house equally. Start with runs that have frozen before, piping in exterior walls, sections above unheated garages or crawlspaces, and hose connections that were not winterized. Interior plumbing surrounded by conditioned space usually deserves less attention than a known cold corner. This triage matters when a warning arrives late: use the limited time on the lines with the clearest path to outdoor temperatures and note them for a permanent insulation, air-sealing, or relocation fix after the event.
If a faucet produces only a trickle, keep it open and check for other affected fixtures. If the frozen section is visible and accessible, warm it gradually with an electric heating pad, hair dryer, or towels soaked in hot water while monitoring the area. Never use an open flame. Stop and call a licensed plumber if the section is hidden, you cannot safely reach it, or normal flow does not return.
After the freeze, inspect before assuming everything survived
Wind chill does not lower pipe temperature below the outdoor air temperature, but air leaks can expose plumbing to that cold more quickly. Homes on crawlspaces, piers, or exterior-wall plumbing deserve extra attention.
Tonight is not the time for a renovation. Use inexpensive immediate protections, then budget after the freeze for insulation, air sealing, heat tracing where permitted, or plumbing relocation if a line repeatedly freezes.
Do not open walls or use open flame or improvised high heat. If the line is inaccessible, leaking, or near energized equipment, control water only when safe and call qualified help.
Concealed piping and electrical exposure are stop points
Do not open walls, dismantle electrical equipment, or improvise high-powered heating around a concealed frozen line. Water from a split pipe can reach wiring, receptacles, panels, appliances, or wet building materials quickly. If the suspected freeze is inaccessible, leakage is near energized equipment, or you cannot isolate the affected branch safely, use qualified plumbing and electrical help. The emergency plan should protect people and limit water damage first; locating and correcting the chronic cold spot comes after the immediate event is stable.
Hard-freeze questions
What can I realistically do in the 30 minutes before a hard freeze?
Disconnect outdoor hoses, close garage doors where plumbing is exposed, confirm heat is operating, open cabinet doors around vulnerable plumbing when that helps warm air reach it, and locate the main water shutoff before you need it. Protect known problem areas first rather than treating every pipe equally. If local guidance recommends allowing a small flow from a vulnerable line during extreme cold, use that selectively and keep drains clear.
Should every faucet be left dripping overnight?
No. Dripping every faucet wastes water and is unnecessary for plumbing that is well inside conditioned space. The measure is mainly for pipes that are unusually vulnerable to freezing, and local utility or plumbing guidance may specify when it is useful. Prioritize maintaining heat, removing outdoor hoses and protecting exposed sections. If you use a drip, choose the affected line deliberately rather than turning the entire house into a blanket response.
What should I do first if a pipe stops flowing during the freeze?
Treat loss of flow as a possible freeze warning. Keep the faucet open if appropriate, identify the likely frozen section, and inspect for leakage as temperatures change. Never use an open flame to thaw piping. If the location is inaccessible, near electrical hazards, already leaking or you cannot safely control the water, shut the main when necessary and call a plumber. A frozen line can split before the leak becomes visible.