How many square feet does a bag of stucco cover?

The question usually means the base coat, since that is where most of the material goes. Two ⅜ in base coats use six times as much as the ⅛ in finish.

Base coat: about 22 square feet per coat

Quikrete’s data sheet gives its 80 lb Base Coat Stucco a coverage of 20–24 sq ft at ⅜ in. Over lath, where the scratch coat has to fill the mesh, real coverage tends toward the low end, so the calculator uses 21 sq ft. A three-coat wall puts on two ⅜ in base coats (scratch and brown), so each bag covers about 10½ sq ft of finished wall. For 100 sq ft that is 9.5 bags, 10.5 with 10% extra — buy 11.

At ½ in, coverage drops to 15–18 sq ft per bag, and at ¾ in to 10–12. On block walls, CMHA lists thinner coats (¼ + ¼ in base), which takes about a third fewer bags.

Finish coat: about 70 square feet

The ⅛ in finish coat covers about 70 sq ft per 80 lb bag, so 100 sq ft takes 1.4 bags before waste — buy 2. Finish coat comes in colours; buy it all from one batch so the wall matches. The block wall underneath, if there is one, is on how many blocks per square foot, and a stone finish instead of stucco is on how much mortar for stone veneer.