How to Paint a Stucco Exterior

Walk the perimeter and tap the wall with a screwdriver handle. Hollow spots mean delaminated stucco that needs re-attaching before paint. Rub a dark rag across the surface — if chalky residue comes off, the existing paint is failing and you will need a bonding primer. Photograph cracks and mark them with blue tape for the repair pass.

Wash at 1,500-2,000 PSI with a 25-degree tip held 18 inches from the wall. Let the stucco dry at least 48 hours. Fill hairline cracks with a paintable acrylic-siliconized sealant; wider cracks (>1/8 inch) need elastomeric patch compound knifed flush and textured to match the surrounding finish.

Apply a high-alkali-resistant masonry primer (e.g., Loxon Conditioner, Zinsser Peel Stop) by airless sprayer and back-roll to work it into the texture. On newer stucco (<1 year old), test pH first — above 10 you must wait longer or use a specific new-stucco primer.

For crack-prone walls, specify an elastomeric coating at 10-12 mils DFT per coat. For smooth stucco in stable climates, a premium 100% acrylic (Sherwin Duration, Behr Marquee) in flat or low-sheen finish is adequate. Spray and back-roll both coats to ensure full coverage in the texture; allow 4 hours between coats in typical US conditions.

Once dry, inspect under raking sunlight for holidays (missed spots) around window returns, under soffits, and in stucco pockets. Touch up with a brush loaded lightly to avoid visible lap marks. Peel masking off while the final coat is still slightly tacky for crisp edges at window and trim lines.