Precast Concrete Cantilever Staircases

Unlike traditional staircases, cantilever stairs create the illusion that each tread floats unsupported a a visual feat achieved through clever engineering. But not all cantilever staircases work the same way.

There are two primary structural approaches:

1. Wall-Anchored Treads – In this model, each step is anchored into a structural wall using internal steel pins or brackets. The wall itself carries the load, allowing the treads to project outward with no visible supports. This design is often seen in floating staircases with open risers and no balustrades. (Shown in this photograph.)

2. Compression-Based Systems – In this approach, each tread bears on the one below it, forming a stable, compressive stack built into an adjacent curved wall. Rather than relying on anchorage, the system works by transferring load downward through the structure. This allows for exceptionally slim stair profiles – with concrete waists as fine as 50mm – while maintaining strength, stability, and aesthetic purity. (Show in photograph below.)

At Kallisto, we specialise in the second type – a precast concrete system that delivers the beauty of cantilevered design with the robust performance of compression-based engineering.