The floating slab is usually used for adjacent uses to the principal residence, such as a driveway, workshop or shed. The resistance of concrete must be high and reinforced with rebar. The thickness of the slab varies depending on the use. In general, this type of slab is poured on a bed of crushed stone to reduce the possibility of accumulation of water under the slab and to minimize the effect of ground motion on the construction. The concrete finish can be anti-skid or semi-smooth depending on the use.