A. All of the existing paint should be removed, preferably with a high-pressure water blaster, with or without fine silica sand. Coatings other than paint may require sandblasting for removal. After stripping, repair any chipped corners, spalls, and cracks with premixed mortar that is troweled on and textured to match the surrounding area. The patched area should be prewetted before applying plaster.
A cement-based paint is probably the best finish for stucco. You buy these products in powder form, mix them with clean water to a brushable consistency, and lay them on heavily enough to fill and seal small cracks and holes. The surface should be dampened immediately before application. Special paints designed for alkaline surfaces are the next...
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