Q: Do I need a special kind of concrete to make a concrete countertop?
A: Ready-mix concrete companies like Quikrete and Sakrete offer special formulations for making pre-cast or cast-in-place concrete countertops. These products feature a “super-plasticizer” additive for a flowable mix at a low water-to-cement ratio. The super-plasticizer delivers a high-flow fluid mix that minimizes the need for mechanical vibration for easy shaping. Mechanical vibration is necessary to release air pockets from the concrete and ensure a solid setup without voids or weak spots. These special countertop concrete mixes reduce shrinkage for long-lasting use and exceed 5,000 PSI compression strength in up to 28 days.
