White Cement: Composition, Qualities, and Uses
White cement is a specialized type of cement that is used for architectural and decorative applications. White cement is similar in composition to ordinary gray Portland cement, but it is unique because of its white color. White cement provides a clean, bright, and uniform appearance. It allows greater design flexibility as well as the creation of visually beautiful structures.
What is White Cement?
White cement is distinguished from regular cement because of its white color. This color is achieved through the careful selection of raw materials. These raw materials have a low iron and manganese content, such as limestone, chalk, kaolin clay, and silica. The manufacturers carefully select the materials and screen for impurities that can cause discoloration.
After the selection of raw materials, they are ground and then blended to achieve the correct proportions. The dust is fed into a kiln and heated to produce the clinker. These are ground into fine dust. Even with the controlled raw materials, many cement producers must mix additives and dyes to the powder to achieve the brightness they desire.
Qualities of White Cement
There are no universal guidelines for ranking white cement qualities, but manufacturers may denote specific qualities using some or all of these criteria.
- Whiteness – Whiteness is the primary characteristic of white cement. Manufacturers will rank the color in terms of its “L” value, or reflectance value. It must have a reflectance value of over 85% to be considered white. The closer the number is to 100%, the whiter the cement.
- Compressive Strength – This refers to the force that a cement can withstand without deterioration. Manufacturers test types of white cement and grade it in terms of megapascals (MPa) or pounds per square inch (psi). This number gives guidance for which applications the white cement can be used.
- Chemical Composition – Manufacturers analyze the raw materials of the white cement to ensure that they meet the standard they require.
- Setting Time – The setting time of white cement will vary according to the properties of the raw materials and external conditions. Cement producers manufacture white cement with both fast, average, and slow set times.
- Fineness – The desired particle size of the white cement will vary in terms of application. Builders used finely ground white cement in applications where appearance matters like artistic and decorative concrete, grout fillers, and thin coating and overlays.
- Admixture Compatibility – Manufacturers combine additives into the white cement to enhance its performance, durability, workability, or strength. Assess these additives to make sure they are compatible with your project.
Types of White Cement
Not all white cement has a standard system of ranking system like white Portland cement which ranks in terms of Types I-V. Instead, manufacturers rank white cement in terms of application, performance characteristics, and specific attributes.
General Purpose White Cement
This cement is useful for a wide range of applications from decorative to practical. It has the essential qualities of white cement such as a white color, adequate compressive strength, easy workability, an average setting time, and long-term durability.
High Early Strength White Cement
High Early Strength White Cement is a type of cement that has an accelerated strength development compared to standard white cement. Cement companies create this cement for a faster setting time and early strength gain where rapid construction is necessary.
White Cement Tile Grout
This white cement is specifically fabricated for tile grout applications to ensure good cohesion, workability, and durability. It fills the gaps between tiles and provides a smooth, white finish.
Waterproof/Water Resistant White Cement
Cement fabricators mix in additives like acrylic or latex to increase the water resistance of white cement. Builders use this type of cement in water-exposed environments where aesthetics are still important like swimming pools, fountains, and water tanks.
There are also varieties of water-resistant white Portland cement. These are sulfate resistant, so they are useful in applications that are exposed to seawater and soil with groundwater with high levels of sulfates.
Specialized Decorative White Cement
Cement manufacturers create specialized white cement products for distinct applications. These include white cement with enhanced brightness, improved color consistency, and smooth or textured surface finish.
Uses of White Cement
White cement has a wide range of uses from the construction industry to the arts.
- Architectural Concrete – Architects use white cement to create architectural concrete which has a uniform white appearance. Builders used white cement in the construction of buildings, bridges, and sculptures where aesthetics are important.
- Precast Panels – Manufacturers use white cement in the production of precast panels which they mold into various shapes and sizes. These are popular for their bright white finish.
- Decorative Finishes – White cement is a primary component in decorative finishes like stucco and plaster.
- Terrazzo – Terrazzo is a floor or wall finish made by embedding marble, glass, or other aggregates into a white cement matrix.
- Tile Grouts – Builders use white cement to make white tile grout adhere and fill the holes between tiles.
- White Mortar – White cement is a primary component of white mortar. This is used in masonry applications where masons want the joints to blend seamlessly with light-colored bricks or stones.
- Decorative or Artistic Designs – Artists, sculptures, and craftsmen favor white cement because of its aesthetic qualities and a high degree of workability.
White Cement Compared to Gray Cement
White and gray cement are similar in strength and workability, but white cement has certain properties that make it more or less useful in certain applications.
- Aesthetics – White cement is brighter and lighter than gray cement, so it allows for greater design versatility and is more visually appealing.
- Color Consistency – White cement has a greater color consistency throughout. This provides a more neutral base which allows dyes to exhibit a more vibrant hue.
- Enhanced Reflectivity – The whiteness of white cement will reflect more light than gray cement.
- Stain Resistance – White cement has greater stain resistance than gray cement, but it can discolor with exposure to certain chemicals or substances. The white cement will show these stains more than gray cement.
- Cost – In general, white cement is more expensive than gray cement.
- Maintenance – Discoloration or surface imperfections will be more visible on white cement, so it requires more maintenance than gray cement.