A concrete slab is a common structural element of modern buildings. Horizontal slabs of steel
reinforced concrete, typically between 4 and 20 inches (100 and 500 millimeters) thick, are most
often used to construct floors and ceilings, while thinner slabs are also used for exterior paving.
Sometimes these thinner slabs, ranging from 2 inches (51 mm) to 6 inches (150 mm) thick, are
called mud slabs, particularly when used under the main floor slabs or in crawl spaces.
Slabs can be on-ground, suspended, or a mix of both. They can be insulated, both underneath
and on the edges