What Temp Should You Drip Faucets? 

Consider dripping a faucet when outdoor temperatures are expected to stay near 20°F (-7°C) or below and the faucet is supplied by pipes in an exterior wall, crawl space, garage, attic, or another unheated area.

Not every faucet needs to run whenever the forecast reaches 32°F. The purpose is to protect vulnerable plumbing during a sustained hard freeze, not to waste water throughout winter.

Which faucets should drip?

Focus on fixtures connected to pipes that are most exposed to cold:

• Sinks against exterior walls

• Plumbing above an unheated crawl space

• Fixtures near a garage or poorly insulated room

• Lines that froze in a previous winter

• Pipes near drafts, vents, or foundation gaps

If you do not know which faucet serves an exposed branch, inspect the plumbing layout or ask a plumber before severe weather arrives.

How much should the faucet drip?

A small, steady trickle is generally enough. The goal is to keep a little water moving and reduce pressure that can build between a faucet and an ice blockage.

Do not open the tap fully. Make sure the drain is clear and can safely carry the water for the entire cold period.

When both hot- and cold-water lines are exposed, some systems may need movement on both sides. The correct choice depends on the fixture and piping arrangement.

Why moving water can help

Flowing water is less likely to remain still long enough to freeze in one vulnerable location. An open faucet can also give expanding water and pressure somewhere to go if ice begins forming.

Dripping is only one layer of protection. It cannot overcome every combination of extreme cold, wind, long exposure, and poor insulation.

Other steps to take before a freeze

• Disconnect outdoor hoses.

• Close and drain exterior faucet supply lines when the system permits it.

• Insulate exposed hot- and cold-water pipes.

• Seal cracks and openings that let cold air reach plumbing.

• Keep garage doors closed when water lines run through the garage.

• Open sink cabinet doors so room heat reaches the pipes.

• Keep the thermostat steady during severe cold.

• If leaving home, maintain indoor heat at no lower than 55°F.

When to stop dripping

You can normally stop after temperatures rise safely above the freezing range and vulnerable spaces have warmed. Check that every faucet has normal pressure and inspect exposed pipes for cracks or moisture.

A pipe may start leaking only after ice thaws. Know where the main shutoff is before temperatures rise.

Frequently asked questions

Should I drip every faucet in the house?

Usually no. Prioritize faucets served by exposed or unheated piping. Local utilities may issue specific instructions during unusual cold.

Should the water be hot or cold?

Cold water is commonly used, but both supply lines can freeze. If both lines run through an exposed area, obtain advice based on the actual layout.

Can dripping guarantee that pipes will not freeze?

No. Insulation, indoor heat, draft sealing, pipe location, wind, and the duration of cold remain important.

What if no water comes out?

The pipe may already be frozen. Keep the faucet open, locate the shutoff, and use only safe gradual warming methods on an accessible, undamaged pipe. Call a plumber if the area is hidden, leaking, or cannot be thawed safely.

Sources

• American Red Cross: Preventing and Thawing Frozen Pipes

• City of Phoenix Water Services: Preventing Damage to Household Plumbing From Freezing Temperatures