With stucco, you can either let it show its natural color, or you paint it. The problem with painting it is that if any water gets in behind the paint, there’s no way for it to get out. And paint cannot reliably keep water out in the first place—there are always cracks forming in the substrate that acrylic or even oil emulsion cannot span. The result is saturated stucco with enough hydrostatic pressure built up in the lower areas to delaminate the paint, forming the sagging pockets of water seen here.

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