A raised flooring system having a sub-work surface is disclosed. The system includes a plurality of pedestal assemblies, a plurality of base floor pads for placing and securing the pedestal assemblies, and a locking assembly for securing the pedestal assemblies to the base floor pads. The locking assemblies include a plurality of projections extending from the pedestal assemblies, a receiving aperture located in each of the base floor pads for receiving the projections in a first position, and a locking aperture in communication with the receiving aperture for locking the pedestal when in a second position to relative to the base floor pad. Inserting the projections into the receiving apertures and rotating the pedestals from the first position to a second position secure the pedestals to the base floor pads, one to another, thus providing exact registration of the pedestals for the ultimate installation of the work floor panels.