Should I leave faucets dripping in a cold snap?

A slight, steady trickle on vulnerable lines is a commonly recommended measure because moving water resists freezing and the open tap relieves pressure. It doesn't replace insulating pipes and keeping cold air out.

Can I thaw the pipe myself?

Gentle warmth on an accessible pipe — a hair dryer on low, warm towels, raising the room temperature — is reasonable. Never use a torch, open flame, or heat gun: pipe thawing fires are common every winter. If the pipe is concealed, call a plumber.

The water is flowing again. Do I still need it looked at?

If the pipe froze hard, it's worth having checked. Splits from freezing sometimes only leak once pressure and temperature normalize, and a small unnoticed split does a lot of damage.

Pipes

Frozen Pipes: What to Do and What Not to Do

No water at a fixture in cold weather, usually with a frozen section in an unheated space. The risk is what happens when it thaws.

A homeowner guide — what may be happening, and what to do next.

If this is an emergency

Uncontrolled water, sewage entering the home, a suspected gas leak, or water near electrical equipment all need immediate action. Shut off the water at the main if it is safe to reach, keep everyone away from hazards, and contact your local emergency services, your utility provider, or a licensed professional as appropriate.

What's happening?

Water expands as it freezes, and in a closed pipe that expansion has nowhere to go. The pressure it creates can split the pipe wall — often not at the ice itself but at a weak point downstream of it. Freezing happens where pipes run through unheated space: exterior walls, crawlspaces, attics, garages, and near foundation vents or open crawlspace doors.

The part homeowners often don't expect is that the flooding usually comes later. While the ice plug is in place it's also blocking flow, so a split pipe may not leak at all. Water appears when things thaw and pressure returns. That's why 'no water at one fixture on a cold morning' deserves attention before it becomes 'water coming through the ceiling.'

Common signs

Symptoms homeowners notice

No water, or a trickle, at one fixture during cold weather
Frost or visible bulging on an exposed pipe
A pipe that feels extremely cold to the touch
One fixture affected while others work, particularly on an exterior wall
Unusual banging or no sound at all when a faucet is opened
Water appearing suddenly once the weather warms

Possible causes

From simple to more serious — not a diagnosis of your specific situation

Pipes in unheated spaces: Crawlspaces, attics, garages, and exterior walls are where freezing almost always happens.
Inadequate insulation: Uninsulated or poorly insulated pipe runs in cold areas.
Cold air infiltration: Open crawlspace vents, gaps at the rim joist, and unsealed penetrations let cold air onto pipes.
Unheated or vacant areas: Rooms closed off, thermostats set very low, or vacant properties during a cold snap.
Exterior spigots and hose bibs: A hose left connected traps water at the fixture, and it freezes there first.
Prolonged extreme cold: Sustained low temperatures freeze pipes that normally survive a mild winter.

How urgent is it?

High — address promptly

A frozen pipe may already be split. Handle it promptly and carefully — and be ready to shut off the water when it thaws.

Low
Medium
High
Emergency

What you can safely check

Simple observations and low-risk checks. None of these require tools you don't have or work you aren't qualified for.

Identify which fixtures have no water — that helps locate the frozen section.
Open the affected faucet slightly so water can flow once the ice starts to melt and pressure has somewhere to go.
Locate your main water shut-off valve and make sure you can operate it before anything thaws.
Look at exposed pipes in basements, crawlspaces, and under sinks for frost or bulges.
Open cabinet doors under sinks on exterior walls to let warmer room air reach the pipes.
Raise the indoor temperature and close crawlspace vents or gaps letting cold air in.
Disconnect garden hoses from exterior spigots.

What not to do

These are the actions that turn a manageable problem into an expensive or dangerous one.

Avoid these

Never use a torch, propane heater, open flame, or heat gun on a pipe. This is a leading cause of house fires during cold snaps, and rapid heating can rupture the pipe.
Don't use an extension cord and space heater arrangement unattended in a crawlspace or near combustibles.
Don't leave the house without knowing where your shut-off valve is and how to close it.
Don't assume a thawed pipe is undamaged. It may be split and waiting for pressure to return.
Don't apply high heat to plastic piping.
Don't force a frozen exterior spigot or valve; cracked bodies leak inside the wall.
Don't ignore a fixture that lost water in freezing weather — check it rather than waiting for spring.

Can I fix this myself?

Safe to check

Observation and low-risk checks most homeowners can make.

Identifying which fixtures have lost water
Opening the affected faucet slightly
Locating and testing the main shut-off valve
Opening under-sink cabinets and raising the indoor temperature
Disconnecting garden hoses
Closing crawlspace vents and sealing obvious cold air gaps

Proceed with caution

Minor actions where instructions must be followed carefully.

Warming an accessible pipe gently with a hair dryer on a low setting or warm towels, never with an open flame, and never in standing water
Adding foam pipe insulation to accessible pipes in unheated areas

Call a professional

Regulated, hazardous, or specialized work. Don't attempt it.

Thawing pipes inside walls, ceilings, floors, or slabs
All repair of split or damaged pipe
Heat cable installation and any electrical work
Re-routing vulnerable piping
Winterizing a property properly

When to call a licensed plumber

Clear signals it's time for professional help

You can't locate the frozen section, or it's inside a wall, ceiling, or floor
A pipe looks bulged, split, or damaged
Water appears anywhere once thawing begins
Multiple fixtures or an entire floor has no water
The frozen section is near electrical equipment
You want vulnerable pipes insulated or protected before the next cold snap

Not sure yet? Read our general guidance on when a plumber is needed.

Questions to ask your plumber

Worth covering before you authorize any work.

Before work starts

1Was the pipe damaged by the freeze, and how did you check?
2Which pipe runs are vulnerable here, and what would you do to protect them?
3Would insulation, air sealing, or heat cable be appropriate in this house?
4Should any piping be re-routed out of the unheated area?
5What should I do to prepare if I leave the house vacant in winter?
6Are you licensed to do this type of work in my area, and can I see your license number?
7Do you carry liability insurance and workers' compensation?
8Will you provide a written estimate before starting work?
9Is a diagnostic or trip fee charged, and is it applied to the repair if I go ahead?
10Does this work require a permit or an inspection?
11What warranty applies to the labor, and what warranty applies to the parts?

What could affect the cost?

We don't publish prices, because real quotes depend on your home, your area, and what's found on site. These are the variables that move the number.

Cost drivers

Thawing vs. repair: Safely thawing a pipe is one job; repairing a split section is another.
Location and access: A pipe inside a finished wall or under a slab is much more work than an exposed one.
Extent of damage: Multiple splits or a long damaged run increases both repair and restoration.
Water damage: If it thawed and leaked, drying and rebuilding finishes is typically the larger cost.
Emergency timing: Cold snaps create demand surges and after-hours rates.
Prevention work: Insulation, air sealing, heat cable, or re-routing pipes is optional but often worthwhile.

More detail on how plumbing work is priced: Plumbing costs — what to expect.

Common questions

Should I leave faucets dripping in a cold snap?: A slight, steady trickle on vulnerable lines is a commonly recommended measure because moving water resists freezing and the open tap relieves pressure. It doesn't replace insulating pipes and keeping cold air out.
Can I thaw the pipe myself?: Gentle warmth on an accessible pipe — a hair dryer on low, warm towels, raising the room temperature — is reasonable. Never use a torch, open flame, or heat gun: pipe thawing fires are common every winter. If the pipe is concealed, call a plumber.
The water is flowing again. Do I still need it looked at?: If the pipe froze hard, it's worth having checked. Splits from freezing sometimes only leak once pressure and temperature normalize, and a small unnoticed split does a lot of damage.

This guide is general educational information, not a diagnosis of your specific situation. Plumbing codes, regulations, and licensing requirements vary by state and locality.