STUCCO
STUCCO BAGS
3-coat ≈ 1 bag / 4 ft²
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RESULT
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FILL IN ABOVE
3-coat ≈ 38 bags / 100 ft² (scratch + brown + finish). 1-coat ≈ 8 bags / 100 ft². 10% waste built in. Estimate only — verify with manufacturer specs.
About this calculator
This stucco calculator estimates 80-lb bag count for an exterior stucco job. Traditional 3-coat (scratch + brown + finish) burns roughly one 80-lb bag per 8 ft² for the scratch coat, another for the brown coat, and one per 12 ft² for the finish coat — about 38 bags per 100 ft² of wall. One-coat synthetic systems run closer to one bag per 12 ft² total. The calculator subtracts window and door area, applies a 10% waste factor, and returns bag counts by coat plus the metal lath sheets needed underneath. ESTIMATE ONLY — exact yields vary by mix design and lath substrate; verify with the manufacturer.
Common questions
How many bags of stucco per square foot?
For 3-coat traditional Portland cement stucco, plan on roughly 38 bags of 80-lb stucco mix per 100 ft² of wall — about 1 bag per 8 ft² for the scratch and brown coats, plus 1 per 12 ft² for the finish coat. 1-coat synthetic systems run lighter at 8 bags per 100 ft². Substrate matters: rough block soaks up more than smooth sheathing, and lath profile (3.4 lb vs 2.5 lb) shifts the scratch coat thickness.
How long does stucco take to install?
A standard 3-coat job on a 1,500 ft² house takes 5-7 working days minimum: day 1 for lath, day 2 for scratch coat, days 3-4 to cure (the brown coat goes on after the scratch is moisture-cured for 48 hours), day 5 for brown coat, days 6-7 to cure, then 1 day for finish coat. Fast-tracking the cure between coats causes the cracking you see on rushed builds.
Can I do stucco over plywood?
Not directly. Stucco needs a weather-resistive barrier (two layers of grade D paper or a coded WRB) plus metal lath fastened through the sheathing into the framing. Skipping either layer voids the warranty and traps moisture against the plywood, which then rots within a few years. The CMU and concrete substrates allow direct application of a bonding coat — frame walls always need lath.