Concrete slabs are referred to as the slab that is used in multi storey buildings. In a double storey home, this will be the concrete floor in between the ground floor and first floor. Some homes also have roof concrete slabs instead of tile roofs.
Generally the concrete floor on the ground level are cast with ready mix concrete by a contractor. The next level is where the engineer designs a slab to carry the floor above, and the builder purchases material to install this concrete floor. Most companies who supply concrete slabs also provide engineering designs, inspections and certifications.
It is easily understood by 90% of builders, architects and engineers and is cost effective and easily installed. Temporary supports are kept in place for around 3 weeks while building above the slab can resume a few days after the slab is cast. Within this type of slab system are 2 types of blocks that can be used, polystyrene blocks or concrete blocks, lintels or ribs remain the same:
This is the standard type of slab, which can be plastered beneath. It's well understood and most common.
It's slightly more expensive and weighs more so transport over long distances costs slightly more.
This type uses the same concrete lintel or rib with a lightweight polystyrene block instead of a concrete block. The cost of this slab is cheaper, and is lighter on foundations and walls (structure of the building) as well as cheaper transport costs over long distances. The lightweight blocks means the slab is installed easier and faster.
The polystyrene cannot be plastered easily and effectively, so it is advised that a ceiling board is used beneath. For many homeowners and builders this is not an issue, as the modern look of dropped ceilings are encouraged.
Also costs more and is usually ideal for shopping centres or tall buildings etc. Generally more dramatic curves and spans can be achieved, but at a higher cost. It is generally common practice in other countries where they build with columns and slabs instead of brickwork as load bearing.
This type of slab is ideal for bigger townhouse projects where time is a factor. They are installed on site with a crane and does not need temporary props.
Crane costs and lead time make this slab cost more than the rib and block system. Builders are limited and can be held back to proceed with a project until the slab supplier deliver the slab and installs it themselves.