How to make white concrete surface with dry shake hardeners?
How to make white concrete surface with dry shake hardeners?
Dry shakes are factory blended materials containing a cementitious binder, aggregates, admixtures and other additives. They may incorporate inorganic pigments or be naturally colored.
When it comes to white or light-colored dry shake hardeners, applying them correctly poses a challenge that many contractors struggle with. To achieve a uniformly colored surface with white dry shake hardener, it is imperative to apply it in at least two layers, totaling 9-10 kg/m2 (2 lb/sqft).
In the accompanying photo, the left area illustrates a single layer application, while the right area demonstrates the preferred two-layer application. The initial layer blends with the base concrete, adopting a light grey hue.
The question arises: Why do contractors frequently apply only one layer?
The cementitious material’s hydration process in dry shake consumes free water from the base concrete, often not leaving enough water for the second layer. This deficiency typically results in dry shake delamination. Additionally, contemporary large panel sizes and low water-to-cement (w/c) concrete mix designs limit the time available for applying multiple layers.
How to apply enough dry shake?
Concria Optima Slab™, a patented technology that empowers contractors to apply a three times thicker layer of dry shake hardener in 2-3 layers effortlessly with our Concria Trowel Hard product. Concria™ Trowel Hard, a nanotechnology liquid, extends the application window for finishers, facilitating the application of sufficient dry shake even in challenging weather conditions such as high heat, direct sun, and wind. By spraying Trowel Hard during finishing, it lubricates the dry-shake hardener, enhancing hydration and “glue” dry shake layers together.
And remember to use only plastic pans and blades when finishing white concrete surfaces.
