The substructure is the component of the building that lies below ground, whereas the superstructure is everything above ground. The goal of a building's substructure is to transfer the loads of the superstructure to the earth beneath. The three main components of a structure's substructure are the foundation, floor slabs, and basement. A ground slab is any flat surface constructed of concrete that extends below grade level. The term "ground slab" can be used interchangeably with "grade beam". A ground slab provides a stable base for all types of construction projects, including buildings, parking structures, and outdoor kitchens. In addition to providing a stable base, ground slabs also act as an electrical conduit and a water barrier. They provide space for wiring and plumbing under your house or building, which can be convenient if you plan to add these services later. If moisture reaches the bottom of your ground slab, it will seep through the slab into the soil below. This prevents water from causing problems for those working on higher floors or in other areas where it may not be able to reach, such as inside walls or ceilings. Ground slabs are commonly found in new construction and major remodels but can also be used as part of maintenance repair work.