How to Stop Pipes From Freezing

Why Pipes Freeze — and Why They Burst

Water expands as it freezes. When ice forms inside a pipe, the expansion itself is only part of the problem — the real damage comes from pressure. An ice blockage seals off a section of pipe, and the water trapped between the blockage and the closed faucet has nowhere to go. As freezing continues, pressure in that trapped section climbs until something gives.

That's why pipes often burst downstream of the ice, not at the frozen spot itself — and why the single most useful reflex when you suspect a freeze is to open the faucet. An open tap gives melting water and pressure an escape route.

Which Pipes Are at Risk

Pipes freeze where heat can't reach them. The usual suspects:

• Pipes in exterior walls — especially kitchen and bathroom supply lines on walls that face the weather, where insulation is thin or missing.
• Unheated spaces — basements, crawl spaces, attics, and garages where plumbing runs through air that tracks the outdoor temperature.
• Exterior spigots and hose bibs — a connected garden hose traps water in the line and can push a freeze back into the wall.
• Vacant units — no one running water, and often a thermostat turned down (or off) to save money. Vacant units are where landlords get hurt worst, because nobody notices the freeze until water is coming through a ceiling.

Preventing Frozen Pipes

Prevention is cheap; water damage isn't. Before and during cold weather:

• Insulate exposed pipes — foam pipe sleeves are inexpensive, cut to length with a utility knife, and take minutes to install on runs in basements, crawl spaces, attics, and garages.
• Seal drafts near plumbing — caulk or foam gaps where cold air blows across pipes: rim joists, holes where lines enter the house, cracked crawl-space vents.
• Keep the heat on — even when vacant — hold the thermostat at roughly 55°F (13°C) or above. Turning the furnace off in an empty unit to save on utilities is how a few dollars of gas becomes a five-figure water loss.
• Let vulnerable faucets drip during hard freezes — a trickle from faucets served by at-risk pipes keeps water moving and relieves pressure if ice does form.
• Open cabinet doors — under sinks on exterior walls, open the vanity or kitchen cabinet so room heat reaches the supply lines.
• Disconnect hoses and shut off exterior spigots — before winter, remove garden hoses, close the interior shutoff to outdoor spigots where one exists, and drain the line.
• Know where the main shutoff is — find it now, test that it turns, and make sure anyone who might respond to an emergency knows where it is. When a pipe bursts, minutes of searching are gallons of water.

What to Do When a Pipe Freezes

You turn a faucet and get a trickle or nothing during a cold snap — that's usually a freeze. Act while it's still just ice:

1. Open the faucet. Both handles if it's a two-handle fixture. This relieves pressure and gives meltwater somewhere to go.
2. Find the frozen section. Follow the line from the dead faucet toward where it passes through cold space — frost on the pipe or a section that's noticeably colder is your target.
3. Apply gentle heat. A hair dryer, a heating pad wrapped around the pipe, or towels soaked in warm water. Work from the faucet end toward the blockage, and keep going until full flow returns.
4. Check the rest of the system. If one pipe froze, others may have too — test every faucet.

When It's an Emergency

A frozen pipe is urgent. A burst pipe is an emergency. If water is escaping anywhere it shouldn't be:

• Shut off the main water valve immediately — this is why you located it in advance.
• Call a licensed plumber — a burst line is not a DIY repair, and a freeze severe enough to burst one pipe has often stressed others.
• Drain and document — open faucets to drain the system, move belongings out of the water, and photograph everything for the insurance claim.

This guide is general home-maintenance information, not professional advice. When in doubt about your plumbing, call a licensed plumber.

For Landlords: Protecting Rentals You Don't Live In

Everything above applies to any home. Landlords have an extra problem: you're not there. The freeze happens in a unit you visit monthly, and whether it becomes a repair or a disaster depends on systems you set up in advance.

• Winterize vacant units — keep heat at 55°F or above, and for extended vacancies consider shutting off the water and draining the lines entirely. Check on vacant units during hard freezes.
• Tell tenants where the shutoff is — at move-in, physically show them the main valve. A tenant who can shut off water in thirty seconds is the difference between a wet floor and a gutted unit.
• Make "keep the heat on" a lease term where appropriate — in cold climates, a clause requiring tenants to maintain a minimum temperature (and to report heat failures promptly) sets expectations before the first cold snap. Check that any clause complies with your state and local law.
• Treat "no heat" reports as urgent — a dead furnace in January is a habitability issue and a frozen-pipe countdown. Respond fast.

Winter emergencies are exactly when real-time maintenance tracking earns its keep. With Kelpic®, tenants report problems through the resident portal with photos attached, you see and triage emergencies as they come in, and every repair lands in the unit's maintenance history — so if the same pipe freezes two winters running, the pattern is sitting in the record instead of in someone's memory.

Frequently Asked Questions