Residential · Clifton, Cape Town · 2024
Cliff House
Cantilevering 18 metres over the Atlantic, a single horizontal plate of space.
The site at Clifton is among the most dramatic in the world—a near-vertical granite cliff descending 70 metres to a boulder beach, with nothing between it and South America. The brief: maximise the view, minimise the presence.
The building is a single horizontal plate, 42 metres long and 12 metres deep, cantilevered 18 metres from a single point of contact with the cliff face. The structural solution is a pre-stressed concrete Vierendeel frame that transfers all loads to a single 2-metre diameter caisson bored 14 metres into the granite.
The ocean edge of the building is entirely glass, structurally bonded into the frame without visible fixings. From inside, the glass appears to dissolve, leaving only a horizontal line of ocean and sky.
Materials
- —Pre-stressed concrete
- —Black granite
- —Structural glass
— Story
The Journey of Cliff House
The commission came from a South African tech entrepreneur who had spent years searching for the perfect site. When she found this cliff face in Clifton, she knew immediately that this was where she wanted to build her forever home. Her brief was both ambitious and terrifying: "I want to feel like I'm floating over the ocean, completely safe yet completely exposed to the elements."
The engineering challenge was unprecedented. Building 18 metres over a 70-metre cliff drop required us to rethink everything we knew about structural engineering. We consulted with naval architects, bridge engineers, and even aerospace engineers to understand how to create something that could withstand the brutal Atlantic storms while appearing weightless.
The solution came from an unexpected source—the principles of suspension bridge design. We adapted the Vierendeel truss system, typically used in bridges, to create a frame that could cantilever such a distance while maintaining the clean, minimal aesthetic our client desired. The entire structure transfers its load to a single point, a massive concrete caisson bored deep into the granite cliff face.
Construction was a dance between precision and courage. Every component had to be helicoptered in and assembled with millimeter accuracy. The glass panels, each weighing over 800kg, were bonded directly to the concrete frame using aerospace-grade adhesive, creating the illusion of a completely transparent edge.
The most profound moment came when we removed the temporary supports. For three heart-stopping minutes, the entire structure hung suspended over the ocean, testing our calculations in real-time. When it held perfectly still, even in the strong coastal winds, we knew we had achieved something extraordinary.
Living in Cliff House has transformed our client's relationship with nature. She tells us that the constant motion of the ocean below has become a meditation, that the changing light throughout the day creates an ever-evolving artwork, and that during storms, the house becomes a front-row seat to nature's most dramatic performances. The house doesn't just capture views—it captures the experience of being alive on the edge of the world.
— Related projects
