Post-tensioning allows longer spans to be used. This means the number of columns per floor is reduced, which opens up the floor area and increase the flexibility of the structure.
Overall Structural Cost
Post-tensioning becomes more economical than plain reinforced concrete slabs for spans greater than 7 metres. This is due to the total cost of materials, labour and formwork being reduced.
Reduced Floor to Floor Height
The slab thicknesses can be reduced when using post-tensioning. This results in savings for facade costs, as well as allowing more floors to be constructed within the original building envelope.
Deflection Free Slabs
Slab deflections can be eliminated with post-tensioning.
Post-tensioning allows for earlier removal of formwork and reduced back-propping requirements. This means faster construction cycles with the quick re-use of formwork.
Column and Footing Design
Reducing the slab thickness has the benefit of reducing the floor dead loads, which results in an economical design of the concrete columns and footings.
Post-tensioned slabs can be designed to be 100% crack free, which means the slabs are essentially waterproof. In order to construct a waterproof slab the choice of concrete mix, curing methods, quality workmanship and detailing are key factors.