Stucco for Building Color and Texture
Traditional portland cement plaster is an extremely versatile, time-tested exterior finish, frequently referred to as “stucco.” It consists of portland cement-based materials and sand, mixed with water to form a workable plaster. The key ingredient, portland cement—the same material that is the basis for the hardened properties of concrete used to build super-highways, bridges, and skyscrapers—provides strength, durability, and toughness in portland cement plaster.
As an exterior cladding, stucco is cost-effective and tough enough to resist damage. That inherent toughness is beautifully complemented by the variety of colors and textures available. Color is determined by selecting cement and aggregate color, and quite often modified by adding mineral oxide pigments to the plaster mix. White portland cement makes it possible to achieve the widest range of colors for the stucco finish, including bright white. Factory prepared finish coat products, which are available in many areas, often contain white cement. These pre-pigmented, packaged cements offer ease of use for achieving the desired stucco color, but it’s also possible to add pre weighed mineral oxide pigments to the finish coat stucco during mixing.
Texture gives substance and character to the plaster surface. It can be used to provide highlights, depth, continuity, segmentation, and even achieve the look of a completely different construction material such as wood timbers, brick, or stone masonry construction. Texture is achieved by selecting aggregate size, controlling finish mix consistency, and using special treatment techniques during and after application of the finish coat plaster.
Sample Textures
Color and texture add dimensions to your projects. To confirm the suitability of a desired color and texture, be sure to ask your plasterer to provide a sample panel for evaluation prior to starting work.
ASTM C 979, Specification for Pigments for Integrally Colored Concrete.