What Is the Difference Between 20 30 and 30 30 Stucco Finish?

August 2025 · Education

The numbers 20/30 and 30/30 refer to the sand grain size used in a stucco finish coat, and they produce noticeably different textures on your wall. Understanding the difference helps you choose the right look for your home and communicate clearly with your stucco contractor.

What the Numbers Mean

The numbers describe the mesh size of the sand used in the finish coat mix. A 20/30 mix uses sand that passes through a 20-mesh screen but is retained on a 30-mesh screen. A 30/30 mix uses finer sand that passes through a 30-mesh screen. The first number indicates the coarse end of the grain range, and the second number indicates the fine end. Smaller mesh numbers mean larger openings, so 20/30 sand has coarser, larger grains than 30/30 sand.

How They Look on a Wall

A 20/30 finish produces a more textured, grainier surface. You can see and feel the individual sand particles, and the wall has a rough, traditional stucco appearance. This is the classic San Antonio stucco look you see on many older homes in Alamo Heights, Monte Vista, and established neighborhoods throughout the city. It hides imperfections well and gives the wall a solid, handcrafted character.

A 30/30 finish uses finer sand and produces a smoother, more uniform surface. The texture is still visible up close but reads as more refined from a distance. This finish is popular on newer construction and modern or contemporary homes where a cleaner, less rustic appearance is desired. It pairs well with sharp architectural lines and minimal trim details.

Which Should You Choose?

Choose 20/30 if you want a traditional, textured stucco look, if you need to match existing stucco on an older San Antonio home, or if you want a finish that hides minor surface imperfections and is forgiving during application. Choose 30/30 if you prefer a smoother, more contemporary appearance, if you are building a modern-style home, or if you want a finish that is easier to clean. Both perform equally well in the San Antonio climate — the difference is purely aesthetic.

When matching existing stucco during a repair, getting the sand size right is critical. A 30/30 patch on a 20/30 wall will look obviously different, even if the color matches perfectly. Our stucco repair team always samples the existing finish before mixing the repair material to ensure an invisible match.

Call (210) 871-8490 for a free estimate. Email info@sanantoniostucco.com.