Cafe cantilever

Our new Cafe in the trees extends out into Whitworth park, and at the far end cantilevers, beyond the end wall of the Learning Studio beneath, to form a sheltered area at the edge of the Art Garden.

Such a cantilever is a challenge for the design team, but one enthusiastically taken on by our structural engineers, Ramboll UK. My understanding of the design solution needed to produce this perfectly horizontal cantilevered space is that the steel frame and concrete slab of the cafe floor are initially constructed in such a way as to tilt slightly upwards. A load is then placed on the end of the upper part of the cantilever, in order to deflect it down. Tests over recent weeks show the process is conforming to expectations, and so a further load to match the final planned calculation of 8 tonnes is now required. At a future date, the glazing components will be installed and the load will be released in a controlled manner. At this point, the floor and roof of the cafe return to a horizontal position.

Despite the robust materials and the heavy loads involved, it all seems quite a delicate operation. Careful calculations ensure the released pressure has no adverse effect on either the structural steel mullions or the finished glazing elements. I’m sure most cafe visitors in the future will be concerned more with delicious food and fine views across the park, than the physics of cantilevers but either way I hope everyone will appreciate the seemingly effortless beauty of this floating space.