Sika® Retarder-50

Sika® Retarder-50 is a liquid admixture designed to retard and stabilize cement hydration without compromising the final quality of the concrete. It allows the mix to remain workable for a longer period and adapts the setting time to the requirements of transportation, placement, and construction.

It is suitable for concrete that must be transported over long distances, projects with extended placement times, large-volume concrete pours, and situations where cold joints must be avoided. It also helps reduce segregation and bleeding of the mix.

The recommended dosage ranges from 0.2% to 2% of the cement weight, to be adjusted based on preliminary tests. It must be added to the mixing water or directly into the concrete mixer; never add it to dry cement. Overdosing can cause very prolonged setting delays. It complies with the UNE-EN 934-2 standard as a setting retarder.