Stucco Calculator
Calculate how many 80-lb bags of stucco you need for a wall from its length and height at a standard 3/8 in coat thickness.
How this calculator works
An 80-lb bag of stucco mix covers roughly 25 sq ft at a standard 3/8 in coat thickness. This calculator divides your wall area by that coverage rate to estimate the bags needed for one coat.
Formula: Bags = Wall area (sq ft) ÷ 25 sq ft per bag.
Worked example
A wall 20 ft long x 8 ft high (160 sq ft):
- Area: 20 x 8 = 160 sq ft
- Bags: 160 ÷ 25 = 6.40 bags
- At $12/bag, that’s $76.80 for one coat.
Coverage reference
| Wall area | Bags needed (25 sq ft/bag, one coat) |
|---|---|
| 80 sq ft | 3.2 bags |
| 160 sq ft | 6.4 bags |
| 400 sq ft | 16.0 bags |
How to measure your wall
Measure the wall’s full length and height in feet — length in the Length field, height in the Width field. If you’re applying a traditional three-coat system (scratch, brown, and finish coats), multiply this calculator’s bag estimate by roughly 3 to cover the full build-up, since the 25 sq ft/bag rate reflects a single coat.
Frequently asked questions
How many bags of stucco do I need for a wall?
An 80-lb bag of stucco covers about 25 sq ft at a standard 3/8 in coat thickness. Enter your wall's length and height and this calculator divides the area by that coverage rate to give you the bag count.
Does this cover a full three-coat stucco system?
No — the 25 sq ft/bag figure is for a single coat. Traditional three-coat stucco (scratch coat, brown coat, finish coat) needs roughly three times the material of one coat, so multiply this calculator's result by about 3 for a full system, or run it once per coat if thicknesses differ.
What's the difference between one-coat and three-coat stucco?
One-coat (or two-coat) synthetic stucco systems apply less total material and are common on new residential construction. Traditional three-coat stucco over a wire lath base is thicker and more durable but uses roughly three times the bagged material — check which system your project specifies before ordering.
Why isn't there a waste allowance for stucco?
Stucco is a mixed, troweled-on material rather than a cut, unit-based product like tile or brick, so its material loss comes mostly from mixing overage and application thickness rather than cutting waste. Most contractors just round their bag order up rather than applying a percentage waste factor.
Does this include the wire lath or scratch coat base?
No — this calculator estimates finish material (stucco mix) only. Wire lath, weather-resistant barrier, and fasteners for the base layer are estimated separately based on your wall's square footage and local code requirements.
Estimates only. Verify quantities with your supplier before purchasing.