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From: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4033560/

I can see that concrete can really go bad after a few hundred freeze and unfreeze cycles:

enter image description here

If an ICF house has insulation from the inside of the house, then the concrete will be cold, if the outside temperature is cold too.

More detail on the layers: insulation for the ICF is grey EPS, 15cm outside, 15cm concrete, inside: 5cm

The question: for how many years can concrete survive without any issue in an ICF house?

I think, because of the 5cm grey EPS insulation from inside, the concrete will receive many freeze/unfreeze states and will go bad earlier/deform/crack?. Living in ~eastern EU, winters are max -10C. But it goes about ~60 days under 0C yearly.

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  • $\begingroup$ Winters are often below -10 in EU - especially in the Alps... $\endgroup$ – Solar Mike Feb 14 '19 at 18:14
  • $\begingroup$ or maybe there is a rule of thumb, that the outside insulation should be 3x better than the inside one! off: updated to eastern eu, sorry, typo $\endgroup$ – cirka547 Feb 14 '19 at 19:05
  • $\begingroup$ Understanding that concrete always will have water content is realising that this is the reason frost and thaw cycles affect it greatly. There are methods to limit this cyclic action but ultimately the problem is water which concrete needs for crystallisation strength. The slower they grow the stronger the concrete becomes but freeze causes fractures which means a fine mix cement to aggregate ratio ought to help. $\endgroup$ – Rhodie Feb 21 '19 at 2:41
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I don't have experience with ICF houses specifically, but I do have experience with specifying concretes for outdoor use with significant frost exposure, so that is what I am basing my answer on.

If you choose the concrete recipe well, 50 years should not be a problem. And with small repairs now and then, neither should 100 years.

This is no worse than using concrete outdoors, where it is directly exposed to the environment. And designing concrete for outdoors exposure for a lifetime of 100 years (with a bit of maintenance) is routine nowadays.

Also remember that the problem is the number of times, the concrete freezes — it can stay frozen for long periods of time without any problems. And the outer layer of insulation will reduce the number of freeze/thaw cycles significantly. (The concrete may freeze during a winter where the outer temperature reaches -10 degrees, but it will not freeze/thaw repeatedly on days where the temperature cycles between, say, +2 and -2 degrees.)

A comment on the article, you are linking to: It may interest you to know that where I live (Denmark), all but possibly one of the concrete recipes, they are testing, would be banned from use, if there is significant frost exposure. I believe they deliberately included concrete recipes that they knew would fail.

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  • $\begingroup$ To add to this answer, this is one of the main reasons why the amount of air in the concrete is specified. $\endgroup$ – hazzey Feb 15 '19 at 13:35

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