Calculate how much stucco, lath, and materials you need for exterior or interior walls. Get bag counts for scratch coat, brown coat, and finish coat using traditional 3-coat or 2-coat application. Enter wall dimensions and get a complete material list. Free to use — no signup required.
Door = 3×7 ft (21 sq ft), Window = 3×4 ft (12 sq ft)
Approximate 80 lb bag coverage by coat and thickness.
| Coat | Thickness | Coverage (sq ft/bag) |
|---|---|---|
| Scratch coat | 3/8" | ~110 |
| Scratch coat | 1/2" | ~82 |
| Brown coat | 3/8" | ~110 |
| Finish (sand float) | 1/8" | ~70 |
| Finish (dash) | 1/8" | ~70 |
| Finish (lace/skip trowel) | 3/16" | ~55 |
| Finish (Santa Barbara) | 3/16" | ~55 |
| 2-coat base (combined) | 3/4" | ~55 |
Stuccoing the front and two sides of a single-story home — 80 linear feet of wall at 9 feet tall with 1 door and 4 windows — gives a net wall area of about 625 square feet. Using a 3-coat system with 3/8" scratch and brown coats plus a sand float finish, you'd need about 7 bags of scratch coat, 7 bags of brown coat, 10 bags of finish, 38 sheets of lath, 1 roll of building paper, and 8 pieces of weep screed. With 10% waste, total material cost runs roughly $350–$500.
| Material | Typical Price |
|---|---|
| Base coat stucco (80 lb bag) | $10 – $15 |
| Finish coat stucco (80 lb bag) | $12 – $18 |
| 2.5 lb diamond lath (sheet) | $6 – $10 |
| Building paper, 60-minute (roll) | $20 – $35 |
| Weep screed (10 ft) | $3 – $5 |
| Corner bead (10 ft) | $2 – $4 |
| Control joint (10 ft) | $4 – $6 |
| Color pigment (per bag) | $2 – $5 |
| Professional install (per sq ft) | $6 – $12 |
For a standard 3-coat system at 3/8" per coat: about 1 bag of scratch coat, 1 bag of brown coat, and 1.5 bags of finish coat per 100 square feet. Add 10% for waste. Thicker applications or textured finishes require more material.
3-coat stucco (scratch coat, brown coat, finish coat) is applied over wood framing with metal lath. It's the most common system for residential construction. 2-coat stucco skips the scratch coat and is applied directly to concrete block, CMU, or existing stucco where the surface already provides a mechanical bond.
Total stucco thickness should be about 7/8" for a 3-coat system (3/8" scratch + 3/8" brown + 1/8" finish). For 2-coat over masonry, total thickness is about 5/8". Going too thin leads to cracking; going too thick causes sagging and increases material cost.
Yes, for 3-coat stucco over wood framing. The lath provides a mechanical grip for the scratch coat. Over concrete block or CMU, lath is generally not required because the block surface provides adequate bond. Self-furring lath is recommended to maintain a gap between the lath and building paper.
Each coat needs to cure before the next is applied. The scratch coat should cure for 24 to 48 hours. The brown coat needs 7 days minimum (traditionally 28 days for full cure, but modern mixes allow 7). The finish coat cures in 24 hours but should be mist-cured for 3 to 5 days in hot or dry conditions.
Most cracks result from improper curing (drying too fast), insufficient thickness, missing control joints, structural movement, or applying the next coat before the previous one has cured. Control joints should be placed every 144 square feet or 18 linear feet to manage cracking.
Typical Results
💡 Mix only as much stucco as you can apply in 1–2 hours — it sets quickly and can't be re-tempered.
Common Mistakes