Air Krete maintains an R-value of 3.9 per inch.
The cured material is friable and will turn into powder when rubbed lightly by hand. Friability does not seem to be a problem in closed cavities, but one may want to test the material before using it in locations subject to extreme vibration.
Air Krete is not flexible after it cures. Since it does not bond to surfaces, shrinkage or movement in a frame wall may open up small gaps. Gaps created by wood framing that has dried out also may be a likely cause of this problem. Air Krete is relatively high in cost. Labor is also an important factor, owing to the work involved in stapling the screen over the cavities.8