CRETARD is a specialized, topically applied concrete retarder/deactivator designed for achieving precise exposed aggregate finishes. When applied to freshly poured concrete, it selectively retards the hardening of the top paste layer while maintaining the setting and strength gain of the underlying concrete. This allows for the easy removal of the top layer by pressure washing within a longer time interval, revealing the aggregates securely bonded to the hardened base.
Unlike conventional methods that require fast washing or other retarding agents, CRETARD controls the depth of hydration stoppage, ensuring uniform and consistent aggregate exposure. It also extends the time window for paste removal, reducing the risk of aggregate pop-out and dislodgement by allowing the concrete to cure properly.
Compared to sandblasting, it is more environmentally friendly and produces a more natural, aesthetically pleasing finish without scarring the surface or disrupting the matrix.