Depressed Slab

What is Depressed Slab

Definition of Depressed Slab in Construction

Description used in the construction industry, that references the reduction of the depth or thickness of a concrete slab. This designation could incorporate an elevation requirement, due to mechanical or electrical equipment height requirements within a mechanical or electric room, or the accommodation of a ” mud slab ” for the installation of tile or a masonry surface that requires a mortar bed. There are several reasons that the top elevation of a slab may require an area that is lower or depressed. Care must be taken to ensure that, if there is a depressed slab identified, the architect and engineer have properly addressed this decrease in the depth of concrete, to ensure that all fire, sound or other rating requirements are maintained. If the entire slab thickness is an important element in the fire rating of this assembly, the depressed area may cause an issue of non compliance.