FACT – Place a dense material such as Portland Cement Stucco/System over a more permeable substrate such as brownstone or even worse, masonry, and FAILURE is guaranteed. As the moisture attempts to exit the building in the colder months, when it hits the interface, by definition, water has to build up at the denser interface so with freeze/thaw the weaker of the two has to fail and delamination occurs. If it is latex or resin modified the process is only accelerated.
This holds true whether it is a Brownstone re-skin or a Portland Cement based FRCM. While great for concrete, if you value your masonry please take this into consideration on your next masonry stabilization or strengthening project. Use of a material such an an inorganic cement which is made to be sympathetic to masonry substrates is always preferred.
