The floor slab is one of the central load-bearing elements in multi-story construction. It absorbs self-weight, finishing loads, and live loads, transferring them to walls, columns, or beams. Depending on the construction principle, one distinguishes solid reinforced concrete slabs, timber joist floors, ribbed slabs, and composite steel-concrete decks. Beyond structural requirements, sound insulation, vibration behavior, and fire resistance duration play decisive roles in design. Flat slabs without beams allow free floor plan design and reduce story heights. Slab thickness significantly influences fit-out, service routing, and the overall cross-section of a building.