How this calculator works
The calculator multiplies total wall length by height, subtracts standard door and window allowances, applies the selected planning coverage, adds 10% for cuts and handling, and rounds up to whole 80 lb bags. Measure each wall section separately; enter the total length and average height, then enter the number of standard doors and windows to exclude them.
A 60 ft × 9 ft wall is 540 sq ft; subtracting a 3 × 7 ft door and two 3 × 5 ft windows leaves 489 sq ft. For the one-coat planning coverage: 489 × 1.10 ÷ 35 = 16 bags.
Match coverage to the system and surface
One-coat and traditional multi-coat systems use different thicknesses, mixes, reinforcement, and substrates. Use the bag manufacturer’s coverage for your exact mix, coat thickness, and substrate rather than treating the calculator’s coverage figures as a product specification. Before ordering, separate base-coat material from finish-coat material and confirm whether your system calls for lath, trim, reinforcement, or a bonding agent. For adjacent finish planning, compare your wall-area measurement with the paint calculator; for an alternative exterior cladding estimate, use the vinyl siding calculator.
Frequently asked questions
How much does a bag of stucco cover?
An 80 lb bag covers roughly 35 sq ft at 3/8 inch for a one-coat application, or about 25 sq ft for a thicker three-coat system.
Should I subtract windows and doors when estimating stucco?
Yes. Calculate gross wall area first, then subtract the area of doors, windows, and other openings. Keep the calculator’s 10% allowance for cuts, corners, and small measurement differences.
How much does stucco cost per square foot?
Multiply the bags required by the price per bag, then divide by the wall square footage. Installed labor, scaffolding, repairs, and finish coats can change the final project cost.
How do I calculate stucco material?
Multiply wall length by height, choose the coverage for your coat system, add a waste allowance, and round up to whole bags.