Concrete @ your Fingertips

Beam and block floors

Typically concrete masonry units are placed between prestressed or reinforced concrete beams to provide a floor capable of taking domestic loading at ground and upper floors. A levelling screed or structural topping maybe required. Expanded polystyrene blocks (EPS) can also be used between the beams but these have no structural resilience and therefore require a structural screed to transfer loads to the beams. These are proprietary systems and must be installed according to the manufacturers details. 

Structural screeds typically require reinforcement consisting of welded steel mesh/fabric. Alternatively, steel fibres or macro-synthetic fibres could be used if advised by the beam and block supplier. Micro-synthetic fibres are not acceptable as they do not provide structural properties.

For housing projects, where this form of suspended floor is popular, see NHBC Technical Extra, Issue 15. This and other technical guides can be downloaded here.

Acknowledgement: The Concrete Society