Do toilets break if they freeze?

yes at the trap, antifeeze is critical

The real answer is "sometimes". If the water is trapped, its' expansion will crack most materials that try to contain it. For my toilet traps in winter, I try to drain them as well as possible and add some RV anti-freeze for the last flush. For my pressure tank and hot water tank, if I expect a sustained hard freeze, I drain them. For light freezes, I just drain a little water to allow for expansion, just in case. If the freezing water has somewhere to expand to, chances of damage are minimal.

Worst case is when water freezes a "lid" that won't shift, then starts to freeze under the lid. Then it needs to go outwards...

YES

I used to rent a house and had some tenants that did not maintain heat. Twice the toilet broke while the pipe did not. Clay will break long before a metal pipe. There is no give in the clay.

In the bowl, sure. In the trap, maybe not.

Do you actually want to find out?

You can add antifreeze every year for twenty years without spending as much time, or money, as you'll spend replacing just one broken toilet. Does it make sense to take a chance?

Sure will. I replaced mine with a "Toto" last year. Gave the old one to a friend. Carefully emptied the trap and set it out under a tree. I forgot about rain collecting in it. Went to load it and found a big patch missing in the trap area.

Harry K

Yes! It is not all that difficult to crack a porcelain toilet. For example, never pour hot water into a (cold) toilet.

yes it will reak the trap area

According to Toller :

Take a glass (glass, not plastic) of water and stick it in your freezer. Odds are that it'll shatter.

As the ice freezes, it becomes more and more rigid (duh ;-), so expansion into adjacent air space is highly restricted.

So even if there's plenty of air space where you think it might expand into, it will still exert very high pressure against the walls.

A "U" of copper pipe, open at both ends and partially filled with water, will split when it freezes. Or at least it did to me ;-)

Well, normal weather is a little different. It comes on much slower and doesn't get as cold. But still, I have always pumped out my toilets and added antifreeze; and will continue to do so.

Two years ago I blew my pipes out with air, and opened 5 drains; as I have for the past 10 years. Then I figured I would save myself a trip below the cottage next spring and closed the drains. Got my first two burst pipes, right next to the drains.

According to Toller :

"Normal" weather here does do those things, and gets much colder.

Water doesn't go through a "plastic" phase when transforming to ice no matter how slow the process is. Or at least, not at anything approaching ordinary pressures.

Frozen water will shatter your toilet. Not sure how warm or cold the weather is where you are but my winters are around -20C (that's -4 Fahrenheit for you guys). Assuming you're talking about a toilet in a building with no heating whatsoever then here's what you do: Basically you have to drain the toilet and pour antifreeze (not the automotive kind) down the bowl - tank stays empty. Goes without saying you won't be using that toilet in the winter.

FYI: every winter we usually get a week or two where the high temperature is -25C, with nights hitting -40C (that's -40F for our friends down south).

replying to Chris Lewis, GossamerG wrote: I removed a toilet a placed it outside, I thought it was completely drained but a small amount of water remained in the trap and it froze overnight and broke a palm size piece out of the bottom of the porcelain. I did not even notice initially, but I found the jagged piece lying on the ground where I had placed the toilet and when I turned it over to set a new wax ring I saw the damage. Caution!