We have an ICF home in Florida that is experiencing small "spider" cracking in several locations on south facing wall.  None of the locations seem to be in a "stressed" area of the wall (not near doors or windows).  The stucco was applied onto a wire lath mesh which was screwed into the ICF using the web tie connectors.  The stucco applicator has been out to the house three times now to "repair" the crakcing and it just keeps re-appearing... in the same spots.  These are not large cracks nor do the seem to be severe....just in locationa that are easily seen by the homeowner while enjoying their backyard activities.  Any thoughts or suggestions on how to fix or what might be the cause of the cracking?

Is this new stucco? How many coats were applied ... 2 or 3? Stucco should be 3/4" thick ... often it only ends up 1/2" with 2 coats. How long between the first coat and the final coat?

Those kind of cracks often occur because the stucco was very wet when applied, and the excess moisture is the reason.

Fixing should be another complete top coat.

Interesting that All-Sask can diagnose a problem from a forum like this. Since when is all stucco required to be 3/4" thick?? Perhaps a better response would be to inquire about the product used?? what about control joints?? Were any employed?? Should they have been installed??? No questions about relative humidity and temperature during installation??? weather conditions between coats???

Well atit .. if you are some kind of stucco pro ... let's hear your wisdom

Sure, just like 99.99% of the questions posted here, the question lacks enough detail to provide ANY type of educated answer. This forum is fraught with tons of ill advised advice based on purported "pro" or "expert" opinion. In the case of the reply here, all that did was suggest that the stucco applicator is a cheat and doesn't know what they are doing, and there is only ONE reason why it cracked. Perhaps the best response to the original question by someone that is knowledgable enough to diagnose such an issue via a forum like this is a litmus test of questions such as: (not limited to)

type and brand of stucco?
was the lath paper backed?
were control joints used?
Do they know temperature and humidity, sun location when subject wall was coated?
Perhaps this wall was coated during or prior to direct hot sun?
Since the questioner is noting that this is on the South facing walls, one could deduce that perhaps the walls are in some stress due to thermal expansion/contraction? (if this is a traditional portland cement stucco, like all portland cement products, it must have a way to expand and contract)
Are there any other "wall faces" that have cracks?
Are edges detailed per the product recommended methods?

If indeed this were caused by too much H2o in the mix, then logically thinking, everywhere the "too wet" material was applied would have the same condition.
How was the product mixed and applied? In a mortar mixer or in an automated rotar-stator type pump with regulated water, mixing and pump settings?
Are there any other signs such as hairline cracks in sheetrock on the interior?? Due possibly to overall building movement or settlement?

There are a ton of variables relating to this initial question which through a process of discussion, one can get pretty close to the underlying causes through a process of elimination and deduction.

If I may, speak my opinion: perhaps the regulars here could do some more thinking before spouting off answers that have not one bit of legitimate "thought process" to them. The ICF industry continually gets hit hard by the "professional building community" (Architects, Engineers and Code Officials to name a few) Because of the off the cuff "I heard it from someone, it sounded good, so I repeat it as if it is the Holy Grail" answers that most of the time have no specific relationship to the questions or worse, provide fodder to suggest that few people in the ICF industry have half a "common sense" knowledge level of concrete, insulation or building science.

I'm no expert, just been at it a long time and seen many people come and go on this forum and in the field. Since this person is located in Florida and diagnosis is near impossible without seeing the project or having a lengthy discussion, I think it would be wise to refer this person to someone familiar with the product (such as a manufacturer's rep) or an independent such as Dennis Sahr at Consultandinspect.com since he is located in Florida. This would end the guessing game and provide the person with an avenue to get the issue resolved rather than guess or make statements of fact that have no validity whatsoever that reinforce the fact that this forum is a place where "regulars" will say just about anything in a reply without a nickle's worth of relevant information. Which leads others that come here for advice to reconsider asking questions because they can see that the advice they could get could be as far from correct as imaginable..... Pretty risky for someone that may be considering ICF for a new build project.....they may just toss the ICF idea and go back to sticks and bricks.

The original intent of this forum was to provide a place to inform, educate and share experiences. This purpose has remained. Theproblem now is that there are too many responses that lack any sort of credible knowledge relationship to the question...... How does one sort these out?? How materials and methods are used are essentially project specific, so answers should be validated by asking additional questions or by providing additional information or parameters for the application being described. Simple caveats such as "here in Florida....we do it this way......for this reason...." And when is the last time you read a caveat that isn't used here..... "we don't vibrate because we know more about concrete science than the multitude of years of research and development that the industry has put into it. We simply tap the walls or use a sawsall to consolidate"....and one would wonder why owners and other building professionals don't consider ICF.....(By the way, tapping or sawsall doesn't do the job)

Well atit, this person just wanted some opinions on possible causes for the cracks. It wouldn't be the first time a stuccoer (or any profession) tried to cover up their own errors with "spin doctor" answers.

I thought they gave a few very specific clues as to the issue. It is always easier to be a critic than to offer some help, so that could be the reason there are so many critics and fewer people in the remaining .01% (to use your stats) trying to be helpful. Perhaps this is the reason doctors don't diagnose over the phone. "I have a chest pain" certainly could be symptoms of a heart attack, or, it could be related to the 4 foot piece of pipe protruding from their rib cage.

Logically, one would wonder why you waste your time with people on here who (based on your verbose critique) are quite obviously far less intelligent than you are. I expect there are other web sites out their for the intellectually superior few, such as yourself.

I was directed to the post by a homeowner that also has cracks on ICF....not my project, but having been in the industry for some time, I get many calls from people that in my humble opinion again, got screwed by careless lousy contractors. Since I was prompted to answer, I did....and yes, you reinforced my position......wasted my time. Yes, my points are "critical", but if you read the answer given earlier, the answer is stated as "matter of fact", now, the homeowner is stuck (in this other case) on the fact that too much water was used in the stucco mix, because some "expert" on GBT said so.

I'll stop wasting time on this one, you may perhaps fit the bill of the issue..... My post offered constructive criticism....you could probably waste your time by re-reading it and tell me why I am incorrect...

Well atit, this person just wanted some opinions on possible causes for the cracks....Then the answers perhaps should be written "maybe" "Possibly"..... but I stand that there wasn't enough information for an educated guess, there are tons of reasons that have NOTHING to do with excessive water in the mix.....