Do I need to reinforce the supporting cabinetry in order to accommodate the weight of a concrete countertop?

Your countertop will weigh approximately 135 pounds per cubic foot. Generally speaking, you don't need to reinforce your cabinetry or floor to support the top. However, if the supporting cabinets are single-wall or made of particle board, vertical plywood reinforcements may be necessary. For more information, refer to "Preparing the Cabinets", pages 159-162, in Concrete Countertops. ... more

Generally speaking, no. If the supporting cabinets are single-wall or particle board, vertical reinforcements may be necessary. ... more