Quote Originally Posted by rumblefish View Post
I see what looks to be white powder & fiber or string like material or growth mixed in underneath & on the outside where the stucco has fallen off.
The white powder could very well be salts.
The whiye strings could be Fiber Glass strands used for crack resistance.
If it was fiber glass and NOT alkaline resistance it would break down when used with Portland Cement Stucco this also would be a very slow process and take many years.
If the stucco was placed over poured in place concrete and the form release oil / surfactant was not removed this could cause detachment or delaminating.