Exterior

Stucco Calculator

Size your stucco mix, sand and lath from wall area and thickness.

sq ft
in
Three-coat over lath is 7/8 in total. One-coat systems are 3/8 to 1/2 in.
Stucco mix bags (80 lb) bags
Masonry sand cu ft
Metal lath sq ft

What you'll need to order

Prices vary by region and haul distance. Get quotes from at least two local suppliers.

How this calculator works

volume ft³ = area × (thickness ÷ 12) × 1.10

Traditional three-coat stucco is 7/8 inch total: a 3/8 inch scratch coat, 3/8 inch brown coat and 1/8 inch finish. One-coat systems over foam board are thinner but need a different base.

Worked example

With wall area 1000 sq ft, total stucco thickness 0.875 in, this calculator returns 133.68 bags.

Waste allowance

The headline figure includes a 10% allowance for waste and over-ordering. The exact requirement is shown alongside it.

Frequently asked questions

How thick should stucco be?

Seven-eighths of an inch for traditional three-coat over metal lath on a frame wall, and half an inch over masonry. One-coat systems apply at 3/8 to 1/2 inch but require an approved foam substrate.

How many bags of stucco per square foot?

At 7/8 inch thickness, roughly one 80 lb bag per 7.5 sq ft of wall. A 1,000 sq ft wall takes about 134 bags, which is why bulk delivery makes sense on anything larger.

Does stucco need lath?

Over wood framing, yes — self-furring metal lath over two layers of weather-resistive barrier. Over concrete or block, stucco bonds directly provided the surface is clean and roughened.

How long between stucco coats?

Let the scratch coat cure 48 hours and the brown coat seven days before the finish. Rushing it causes cracking as the underlying coat continues to shrink beneath a hardened surface.