Are IBCs frost-proof?

[trubble]

Hi, I've just had three IBCs delivered for rainwater storage - 2 for fitting under the house, feeding toilets, and a third to be stored outside to be used for garden irrigation.
If an IBC is full of water which then freezes, does it crack the container? I think it's polypropylene, which is fairly flexible. Don't mind the contents freezing, it's just any potential damage to my precious IBCs that I'm worried about.
Any experience of non-insulated IBCs and big blocks of ice would be appreciated! Ta!

[Countrypaul]

I thought most IBC were HDPE - are you sure yours is polypropylene?

The force created as water turns to ice in a confined space is phenominal and if the IBC was full and sealed it would almost certainly rupture. Ice occupies nearly 10% more volume than water - it has to go somewhere.

Paul

[mespilus]

Water increases its volume by around 10% when it freezes,
think of all that freeze thaw damage that reduces mountains
to scree.

Polypropylene may well be fairly flexible, but it, and HDPE do not normally
exhibit elastic recovery:

A piece of paper is flexible, but a properly applied bead of silicone sealant
waterproofing the joint between a bath and a tiled wall will stretch,
(when the bath is filled with water + person/people), and return to its
original shape when the bath is emptied.

Resolution:
either run off some water when frosty weather approaches,
to less than 90% capacity,
or,
loosen the lid to allow some expansion space.

[knighty]

I use them a lot at work, and have never heard of one splitting due to freezing..... infact they're pretty hard to kill (unless someone in a forklift decides to have a jousting match with one)

it would have to be very cold, for a very long time for the water to freeze right in the middle...

and it's only a real threat if the ibc is full (or nearly full), and freezing will only happen in winter... when you should have plenty of rainfall.... so you could always just empty some out ?


(the underground ones shouldn't freeze at all)

[guydewdney]

my precious IBCs

just how much did you pay? 20 quid is the norm round here....

[trubble]

Hi, thanks for the replies - I was guessing about the polypropylene! HDPE sounds much more techernical.
So basically, as long as I fit an overflow drain about 100mm from the top, I should be ok?
I'm near Manchester and found some clear (not black) IBCs being sold in Trafford Park at £25 for two collect only - I got three delivered for £90 as I can't get them on the roofrack 
I NEED a trailer!
They're advertised as being stained, but in they're fantastic condition with the proper steel pallet and cage, valve and screw caps etc, I reckon they're almost brand new.
Not sure if I'm allowed to advertise, so I won't!
Next stop - new shed and woodstore extension... all with guttering 

[Rooster]

I've had the clear ones well and truly freeze up without any problems.

They weren't sealed though but were full to within 100mm of the top.

Only time I had any damage was when a neighbour tried to force open the valve when it was frozen. 

There is one I must have been using for 12-14 years and it was years old when I got it!

[trubble]