What’s the Difference Between Plaster and Stucco?

Plaster and stucco are both extremely common building materials, especially for residential construction. They are quite similar in many ways. They both, for example, are highly durable, lasting for years on end while providing some outstanding fire resistance. They make for an attractive alternative to siding, and are generally pretty low-maintenance.

Various versions of plaster and stucco have been used in construction for thousands of years. While today’s versions of the materials are manufactured in mass volumes, there is still a level of artistry to them that doesn’t exist for other exterior finishing materials in residential construction.

So now that you know how they are alike, how exactly are plaster and stucco different? What separates the two when we’re talking about potential exterior finishing materials for new construction? Here’s some information from a stucco contractor in Bluffton, SC to help you better understand these differences.

Composition

Stucco is a specific type of exterior plaster, but plaster is not necessarily stucco. (Think “a square is a rectangle, but a rectangle is not necessarily a square.”) Products you’ll find on the market labeled “exterior plaster” are made from mixtures of lime, water and plaster of Paris. However, stucco is a type of twist on this composition, and instead features a mixture of lime, Portland cement and sand. These differences in the materials used in their composition affect both how the material is applied to the exterior of a building and the locations in which those materials can be used.

Application

As we just mentioned, there are some differences in how stucco and plaster are applied to the exteriors of buildings. Plaster is a little more versatile than stucco, as it can be used both inside and out, while stucco is only meant for exterior use. Stucco is a bit rougher in texture and holds up better than many types of plaster. But exterior plaster is more versatile in nature, meaning it can be applied to many different types of surfaces, including concrete and drywall. You must properly prepare exterior surfaces before applying stucco—exterior plaster is not going to be quite as picky.

Versatility

Let’s talk a bit more about those differences in versatility. As we mentioned, exterior plaster is more versatile than stucco. Stucco can only be applied to some types of surfaces, but plaster can be applied to both smooth and rough textures. Plaster can also be poured into molds and allowed to set to create much more intricate designs. Stucco cannot be molded in the same way.

Installation

Both stucco and plaster must be installed by highly trained experts who have gone through significant on-the-job training to learn the process. Stucco is generally applied in three layers over a wire lath, with the first coat being a “scratch” coat, the second being a “brown” coat and the top coat being the distinctive textured appearance. While exterior plaster can also be applied in this way, there are more options for installation.

For more information about the differences between plaster and stucco, contact Spring Construction to speak with a stucco contractor in Bluffton, SC.

Categorised in: Stucco