# Frozen Water & Busted pipes

**URL:** <https://boards.straightdope.com/t/frozen-water-busted-pipes/7690>\
**Category:** Factual Questions\
**Created:** [February 21, 2000, 4:55pm UTC](https://boards.straightdope.com/t/frozen-water-busted-pipes/7690 "2000-02-21T16:55:00Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![drollman](https://avatars.discourse-cdn.com/v4/letter/d/f04885/32.png) [@drollman](https://boards.straightdope.com/u/drollman)\
**Post date:** [February 21, 2000, 4:55pm UTC](https://boards.straightdope.com/t/frozen-water-busted-pipes/7690/1 "2000-02-21T16:55:00Z")

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If cold makes things contract and heat makes things expand, how does frozen water burst a pipe?

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My fate keeps getting in the way of my destiny.

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**Author:** ![WillGolfForFood](https://avatars.discourse-cdn.com/v4/letter/w/82dd89/32.png) [@WillGolfForFood](https://boards.straightdope.com/u/WillGolfForFood)\
**Post date:** [February 21, 2000, 5:13pm UTC](https://boards.straightdope.com/t/frozen-water-busted-pipes/7690/2 "2000-02-21T17:13:00Z")

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Although most things contract as they get colder, water actually _expands_ as it drops below 4 degress centigrade, and expands further when it solidifies to ice. It’s the expansion-on-solidification that bursts pipes.

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**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\
**Post date:** [February 21, 2000, 5:15pm UTC](https://boards.straightdope.com/t/frozen-water-busted-pipes/7690/3 "2000-02-21T17:15:00Z")

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The transition from liquid water to ice is an exception to that rule. Another consequence is that ice floats instead of sinking.

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**Author:** ![RussellM](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@RussellM](https://boards.straightdope.com/u/RussellM)\
**Post date:** [February 21, 2000, 5:17pm UTC](https://boards.straightdope.com/t/frozen-water-busted-pipes/7690/4 "2000-02-21T17:17:00Z")

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Q. Why does ice float on water?  
A. Ice is less dense than water (about 10% difference IIRC). The ice becomes less dense by virtue of increased volume.

So, why do pipes burst ?  
The water freezes and expands, bursting the pipe. Some time later the ice melts, and then you discover you are flooded.

Russell

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**Author:** ![manhattan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/manhattan/32/7_2.png) [@manhattan](https://boards.straightdope.com/u/manhattan)\
**Post date:** [February 23, 2000, 11:12pm UTC](https://boards.straightdope.com/t/frozen-water-busted-pipes/7690/5 "2000-02-23T23:12:00Z")

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This is a short, off-topic post that is intended to fix the “2029 problem” and send this thread back into the normal place on the thread list.

Not that busted pipes aren’t important and all…

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Livin’ on Tums, vitamin E and Rogaine