Stucco in direct contact with any of the building papers or housewraps decreases moisture permeability and increases the capillary transference.
Therefore the must be installed need for the drainage plane second layer.
Imagine being in a tent during a rainstorm no leaks until contact is made with the tent material. Once this happens the leaks can’t be stopped until the entire system is dried again.
All housewraps go against the sheathing, under a layer of another material, not in direct contact with the stucco. Reversal of this application and you’ve wasted the money spent on housewrap because it no longer performs as intended.
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