Stucco Material Coverage Calculator
Calculate the amount of cement, sand, lime, and water needed to stucco a wall or surface area. Supports single-coat and three-coat systems.
Formulas Used
Net Area: Net Area (ft²) = Length × Height − Openings Area
Mortar Volume per Coat: Vmortar = Net Area × (Coat Thickness / 12) × Waste Factor
Dry Ingredient Volume: Vdry = Vmortar / Yield Factor (0.67)
Individual Material Volumes:
- Vcement = Vdry × (Cement Parts / Total Parts)
- Vlime = Vdry × (Lime Parts / Total Parts)
- Vsand = Vdry × (Sand Parts / Total Parts)
Cement Bags: Bags = (Vcement × 94 lb/ft³) / 94 lb/bag
Water: Water (lb) = w/c ratio (0.50) × Cement Weight (lb); Gallons = lb / 8.34
Sand (tons): Tons = (Vsand × 100 lb/ft³) / 2000
Assumptions & References
- Three-coat system coat thicknesses: Scratch 3/8", Brown 3/8", Finish 1/8" (total 7/8") per ASTM C926.
- One-coat system thickness: 3/8" combined base and finish coat.
- Mortar yield factor of 0.67 accounts for air voids filling during mixing (industry standard approximation).
- Portland cement bulk density: 94 lb/ft³ (1 standard bag = 94 lb). Reference: PCA Design and Control of Concrete Mixtures.
- Hydrated lime bulk density: 40 lb/ft³. Reference: ASTM C207 Type S hydrated lime.
- Sand bulk density: 100 lb/ft³ (dry, loose). Reference: ASTM C897 aggregate for stucco.
- Water-cement ratio: 0.50 by weight — typical for workable stucco mortar.
- Water density: 8.34 lb/gallon at 60°F.
- Waste factor default 10% accounts for mixing losses, over-application, and spillage.
- Mix ratios follow Portland Cement Association (PCA) and ASTM C926 recommendations for stucco coats.
- Calculator does not account for fiber mesh, bonding agents, or pigments.