What is a Post-Tensioned (PT) Slab?
A Post-Tensioned (PT) slab is a type of reinforced concrete slab that uses high-strength steel tendons to improve performance and reduce material usage. It is one of the most widely used slab systems across Australia—especially in large-scale developments—due to its ability to span longer distances, reduce concrete volume, and speed up construction timelines.
The system works by placing ducts or sleeves within the slab formwork before concrete is poured. After the concrete gains sufficient strength, steel strands (tendons) are inserted and then stressed (tensioned) using hydraulic jacks. This tensioning process compresses the concrete, significantly improving its load-carrying capacity and crack resistance.