ADAMS KARA TAYLOR LTD
LITTLEHAMPTON WELDING LTD
The East Beach Cafe is a south-facing single storey building on the seafront in Littlehampton. The building has a narrow footprint determined by the dual constraints of the promenade at the front and the public car park running along the rear of the site. The southern façade is predominantly glazed to afford the maximum views from the café to the sea, whilst a level of interest and detail has been achieved on the rear of the café by the rippling form.
The shell of the building provides both its skin and structure, comprising a steel shell formed from horizontal ribbons which are curved around a series of vertical slices. This ‘monocoque’ steel shell in which all parts act together is similar to the hull of a ship.
The exposed seaside location subjects buildings to heavy weathering, with the high salt content of the air speeding the natural degradation of all materials. With this in mind, the designer opted for naturally finished materials that respond to the local environment. The 8mm thick mild steel shell that forms the outer skin was initially allowed to rust to gain texture, colour and character. Once the surface had weathered, an oil based coating was applied to halt and inhibit any further corrosion.
The shape of the building is informed by the ways in which steel can be manipulated; jigsaw-puzzle like pieces were precision cut by machine and used as a template for curving ribbons formed and welded within the controlled environment of Littlehampton Welding’s workshop. The structure was modelled using a finite element design package, with the designer’s digital 3D model of the complex geometry directly imported into the analysis model. This allowed the inherent stiffness of the sculptural shell to be modelled with the latest digital analysis methodology partly developed at AKT. The model was used to identify those areas of the shell where the curvature was not sufficient to provide the required stiffness. A series of 150mm deep steel ribs were then introduced at regular centres to stiffen the structure. The glazed wall facing the sea is articulated by a series of columns fabricated from steel plate which incorporate rainwater pipes, glazing frames and shutter guide rails. The shell was prefabricated, dismantled and then brought to site in four sections, which were then subsequently welded together.
As a single storey building the resulting foundation loads were relatively low, and simple economic strip foundations were adopted, bearing onto the sand below. The lateral loads resulting from the shell behaviour are resisted by the in-situ topping to the beam and block ground floor slab.
This unique structure is largely formed of steel plates welded into a series of “wave” shapes forming an irregular shell. Situated at the top of the beach, the exterior is reminiscent of wave-shaped rocks, whilst the interior is rather like a cave. Clearly the ongoing protection of the shell will be crucial to maintaining its future effectiveness.
The project is already enlivening this part of the seafront. The high quality of the extensive shaping and welding has been key to this extraordinary and successful project.