Can Hamburger Buns Save Your Pipes from Freezing? - WIRED

Why do water pipes burst in cold weather anyway.

When the liquid water inside turns to ice, the pressure is great enough to break the steel container.

(Unless you collect rainwater or make water from hydrogen and oxygen, you probably have one.) If it gets too cold, the water can freeze and literally burst your pipe.

In the southern states, this ground temperature isn't very likely to get below freezing—so water in the pipes will also be above freezing (and stay liquid).

Although there is a small temperature difference between cold water (let's say 1 degree Celsius) and warm ice (0 C), there is a huge energy difference.

It takes quite a bit of energy to change water from its solid phase to a liquid.

If you want to take this ice at 0 C and turn it into water at 1 C, it would take 344,000 joules of energy (plus a tiny bit more energy to raise the temperature of water)?

That also means that you need to remove quite a bit of thermal energy from your pipes to get them to freeze.

One cold night probably isn't going to be enough to make your pipes burst.

OK, imagine you’re inside of a water pipe.

(Yes, you are super tiny now.) If the water is stationary, you might be stuck in a part of the pipe that is exposed to cold air.

You could actually freeze, and then you would have to break the pipe.

You pass through the section of cold pipe and you get cold—but you don't freeze.

Oh, but more water from the main underground line is coming into that cold part of the pipe?

Remember, the water pipe is at ground temperature, which is almost certainly not below freezing.

So, the incoming water isn't super cold, and hopefully it won't freeze.

The insulation decreases the rate that energy is transferred from the hot thing to the cold thing through a thermal interaction.

If you put a cold drink out on a table, energy is transferred into the drink to cause it to increase in temperature.

For the foam insulation around a pipe, the water is warmer than the air, so this decreases the rate of energy transferred out of the water.

Remember, if you remove enough thermal energy from the water, it will make a phase transition from a liquid to a solid—and that's the bad part.

Yes, putting hamburger buns around an exposed water pipe will increase the insulation and reduce the chance of having a frozen (and burst) pipe?

Losing a bunch of buns is probably cheaper than fixing a broken water pipe.