How big is a Flexx Block?
Blocks are 16″ tall and 48″ wide. You can use blocks, which produce concrete walls from 6″ thick to 12″ thick, in 2-inch increments. The insulating walls are 2″ thick. CAUTION! Order blocks by the Concrete Wall Thickness, not the overall thickness. For instance, 8″ blocks (for an 8″ concrete wall) are 12″ thick, overall.