DESIGNING with COLORED CONCRETE
Concrete enhanced with color and texture - once considered a niche product confined to use in the residential market - is now widely used in building and renovating major public and commercial sectors.
As property owners and operators have recognize the benefits, and architects and designers have become intrigued with the diverse and exciting creative opportunities, the increasing volume of colored architectural concrete is expected to grow at a rate of over 25% annually. Among the benefits, colored and textured concrete can mimic brick, tile, granite, limestone, or even wood, providing long-term value, extended durability, lower maintenance and most important of all, a lower cost than these traditional building materials typically offer.
For many applications, uncolored concrete may become a thing of the past. For most businesses, it is very appealing have a colored entrance against just gray concrete. It attracts more traffic. The picture above is a perfect example. Eye-catching colored concrete enlivens public areas and the contrasting shades of concrete can introduce variety within large expanses of open spaces such as business and retail centers, and subtle harmonizing colors can be used to blend path ways, planters, curbs, and walkways. The rich patina and natural texture of colored concrete are now designs elements in interior walls, exterior hard landscaping, retaining walls and exposed concrete floors.
There are three ways of coloring concrete: integral color (the coloring agent is added during mixing); dry-shake color hardeners (color are broadcast onto the surface of freshly poured concrete); and reactive, penetrating stains (applied to new or existing uncolored concrete surfaces after the concrete has been finished). Stains add unique, variegated color that can be used for distinctive marbleized looks, faux finishing, and a wide range of other effects.
To obtain the best result in selecting colored concrete products the gray color tone of Portland cement must be taken in consideration; sometimes the use of white cement may be appropriate if the coloration desired is bright and intense. Also a lower water-cement ratio improves the color intensity and durability of integrally colored architectural concrete.
Techniques like flat troweling of concrete containing coloring admixtures will produce a variegated finish. A sandblasted finish will create an inviting, uniform aggregate exposure, less likely to show small color variations between one batch and another, while the use of a surface retarder will create a coarser, bolder finish.
Proper curing of colored architectural concrete is extremely important. "Color-matched materials specifically designed for curing colored concrete allow concrete to develop its full color and strength potential with a low application rate that reduces film buildup and material costs. Proper curing increases concrete strength and improves abrasion resistance while protecting the surface from staining. The resulting concrete surface is easier to clean and maintain.
Producing high quality, value-added colored architectural concrete is a collaborative process, and it is not hard to achieve, says Estella from Dare Concrete. Using a full system of compatible materials, working collaboratively with product experts and contractors, the designer can easily achieve concrete of enduring beauty and superior durability and performance. The process of blending quality products and teamwork is the key for the success of any project.