beam column slab construction

Beam and Slab Floor System

This system consists of beams framing into columns and supporting slabs spanning between the beams. It is a very traditional system. The relatively deep beams provide a stiff floor capable of long spans, and able to resist lateral loads. However, the complications of beam formwork, co-ordination of services, and overall depth of floor have led to a decrease in the popularity of this type of floor.

beam column slab construction

beam column slab construction

The traditional reinforced concrete beam-and-slab floor has an economical span ‘L’ of D x 15 for a single span and D x 20 for a multi-span, where D is the depth of the slab plus beam. The depth of slab between the beams can be initially sized using the span-to-depth ratios for a flat plate. Prestressing is not normally used with this system.


  • Traditional effective solution
  • Long spans.


  • Penetrations through beams for large ducts difficult to handle
  • Depth of floor
  • Greater floor-to-floor height.