Every winter, one of the most common questions homeowners ask is: What temperature do pipes freeze? The short answer: Pipes can begin to freeze when temperatures drop to 20°F (-6°C) or lower. But the actual freezing point of pipes depends on many factors, indoor temperature, pipe insulation, location inside the home, pipe material (PEX, PVC, copper), exposure to wind, and more.
In this complete guide, you’ll learn:
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At what temperature water pipes freeze
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The difference between indoor and outdoor pipe freezing
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When PEX, PVC, and copper pipes freeze
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What temperature pipes burst
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Regional variations (Texas, Canada, UK, Florida)
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How long it takes pipes to freeze
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How to stop your pipes from freezing during winter or power outages
At What Temperature Do Pipes Freeze?
Water freezes at 32°F (0°C), but your pipes usually don’t freeze at 32°F. Pipes typically start to freeze at 20°F (-6°C) after a few hours of exposure. This applies to:
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indoor pipes
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outdoor pipes
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PVC, PEX, and copper
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house, apartment, basement, attic, crawl space, and mobile home pipes
- Below 20°F, unprotected pipes are at serious risk.
At What Temperature Do Water Pipes Freeze?
Uninsulated water pipes begin freezing at around 20°F (-6°C).
However, freezing can occur earlier if:
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the pipe is near an exterior wall
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wind chill reaches the pipe
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no heat source is nearby
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the pipe is in an unheated space
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temperatures stay below freezing for many hours
What Temperature Do Pipes Freeze In a House?
Inside a house, pipes can freeze when indoor temperatures drop to 55°F (13°C) or lower for extended periods, especially near:
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exterior walls
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north-facing walls
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unheated basements
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crawl spaces
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attics
The house temperature at which pipes freeze:
- Below 55°F (13°C) = pipes at risk
- Below 50°F (10°C) = higher risk
- Below 45°F (7°C) = dangerous
- Below 40°F (4°C) = high freeze probability
What Indoor Temperature Do Pipes Freeze?
A pipe inside your home begins to freeze if:
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the air around it falls below 32°F (0°C),
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even if the rest of the home is warm.
This happens often in:
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attics
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crawl spaces
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under sinks
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behind cabinets
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unheated garages
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basements
At What Temperature Do Outside Pipes Freeze?
Outdoor pipes freeze much faster because they’re directly exposed.
Uninsulated exterior pipes freeze at:
- 25°F (-4°C) after a few hours
- 20°F (-6°C) quickly
- 15°F (-9°C) extremely fast
Wind chill accelerates freezing on metal pipes.
At What Temperature Do PEX Pipes Freeze?
PEX pipes are flexible, so they freeze less easily, but they still freeze. PEX pipes typically freeze at: 20°F (-6°C), Similar to other pipes, but they are less likely to burst because they expand.
At What Temperature Do PVC Pipes Freeze?
PVC pipes are the most fragile when frozen. PVC pipes freeze at: 20–25°F (-6 to -4°C), They also crack easily once frozen.
At What Temperature Do Copper Pipes Freeze?
Copper pipes freeze faster because metal conducts cold. Copper freezes at: 25°F (-4°C), Bursts most often below 20°F (-6°C)
These are the highest-risk pipes.
What Temperature Do Gas Pipes Freeze?
Natural gas doesn’t freeze in normal winter conditions.
Gas pipes do not freeze, but valves or regulators can freeze if moist air enters.
What Temperature Do Heating Pipes Freeze?
Hydronic heating pipes (radiators, boilers) can freeze at: 32°F (0°C) for the water itself. Most systems freeze when home temp drops below 40°F (4°C)
What Temperature Do Pipes Freeze in Texas?
In Texas homes, pipes freeze earlier because houses often lack insulation. Texas pipes freeze around: 28°F (-2°C) or even higher
Because pipes are unprotected, freezing can occur within 1–3 hours.
What Temperature Do Pipes Freeze in Canada?
Canadian homes are better insulated. Pipes freeze at: 20°F (-6°C) Outdoor lines freeze even below 25°F (-4°C)
What Temperature Do Pipes Freeze in the UK?
In the UK, unlagged loft pipes can freeze when outdoor temps reach: 25–28°F (-4 to -2°C), Attic pipes are most vulnerable.
What Temperature Do Pipes Freeze in Florida?
Florida homes have almost no pipe insulation. Pipes freeze at: 30–32°F (-1 to 0°C), Very high risk during sudden cold snaps.
Specific Home Types
What Temperature Do Mobile Home Pipes Freeze?
Mobile home pipes freeze earlier because they’re usually exposed underneath.
Freeze around 28°F (-2°C)
High risk at 25°F (-4°C)
Skirting and heat tape are essential.
What Temperature Do Pipes Freeze in an Apartment?
Apartment pipes freeze if:
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the unit is vacant
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windows are broken
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heating fails
Most apartment pipes freeze when indoor temp drops below: 50°F (10°C), Exterior walls can freeze earlier.
Specific Locations in the House
At What Temperature Do Attic Pipes Freeze?
Attics get extremely cold. Pipes freeze at: 28°F (-2°C), Rapid freezing at 20°F (-6°C)
Crawl Space Pipes
Crawl spaces get direct cold exposure. Freeze point: 25°F (-4°C), Often freeze first in winter storms
Basement Pipes
Basements freeze at: Below 32°F (0°C) for long periods, Below 25°F (-4°C) = high risk
Underground Pipes
At What Temperature Do Underground Pipes Freeze?
It depends on depth and soil insulation. Shallow lines freeze at: 20–25°F (-6 to -4°C), Deep lines rarely freeze unless temperatures stay below freezing for days.
Specialty Pipe Types
Irrigation Pipes
Freeze at 20–25°F (-6 to -4°C).
Sprinkler Pipes
Freeze quickly at 25°F (-4°C).
Pool Pipes
Freeze at 28°F (-2°C) if pump is off.
At What Temperature Do Pipes Freeze and Burst?
Pipes burst AFTER freezing, not while freezing. Risk increases:
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once water expands into ice
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when pressure builds behind an ice blockage
Burst temperature threshold:
- 20°F (-6°C) and below
- Severe bursting at 15°F (-9°C) or lower
How Long Does It Take Pipes to Freeze?
- At 20°F (-6°C): 2–6 hours for exposed pipes, 6–12 hours for indoor pipes
- At 0°F (-18°C): Pipes can freeze in 1–2 hours
What Temperature Do Pipes Freeze Without Heat?
During a power outage, pipes begin to freeze when the indoor temperature falls below 55°F (13°C), reaching danger zone quickly.
What Temperature Should You Keep Your House To Prevent Freezing?
To prevent frozen pipes:
- Keep home at at least 55°F (13°C)
- 60–68°F (15–20°C) is safer during extreme cold
When Do You Need to Worry About Pipes Freezing?
You must worry about freezing when:
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Outdoor temps hit 28°F (-2°C)
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Home temp drops below 55°F (13°C)
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Pipes are near unheated walls
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You live in a warm climate (higher risk)
What Temperature Do Pipes Freeze?
Here’s the quick reference guide:
Freezing threshold
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20°F (-6°C) = most pipes freeze
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25°F (-4°C) = metal pipes freeze outside
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32°F (0°C) = water freezes, pipes may freeze if exposed for hours
Burst risk
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Pipes burst most often below 20°F (-6°C), especially copper and PVC.
Indoor freezing
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Home temps below 55°F (13°C) can lead to frozen pipes.
Outdoor freezing
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Exterior pipes freeze rapidly at 25°F (-4°C) or lower.
Pipe materials
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Copper: freezes fastest
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PVC: cracks easily
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PEX: freezes but rarely bursts
