National Automotive Innovation Centre

A mighty concrete structure lies at the heart of Cullinan's car research centre in Coventry, writes Pamela Buxton

At some 33,000m2, the National Automotive Innovation Centre at Warwick University is the largest single building ever completed by Cullinan Studio. It is a hybrid building in terms of both purpose and materials. Designed to synthesise industry, research and teaching, the four-storey building uses both structural steel and concrete and is topped with a steel and glulam roof that oversails to create a welcoming entrance.

Each material, explains Cullinan Studio practice leader Roddy Langmuir, is doing what it does best: “It’s best not to force them to do a job that they’re not good at.” In the case of concrete, this entails forming the massive in-situ, flat slab frame, with core walls for stability and a 7.5m column grid. Concrete was the only viable choice to deliver sufficient thermal mass and provide the robust and flexible internal environment required for the facility, which includes everything from virtual reality suites and driving simulators to design and engineering halls.

At the entrance, the structure included slab cantilevers of up to 3m to create a series of tiers surrounding a dramatic atrium. Use of concrete also enabled 15m spans over both the double-height engineering hall and the design studio, which was stacked above it on a suspended slab. Achieving this was particularly challenging, says Langmuir, given the need to limit live-load tolerances to exceedingly small amounts (microns) to suit specialist equipment such as scanning machines. The structure also needed to accommodate heavy (3-tonne) clay vehicle models anywhere on the slab.

After close collaboration with the client stakeholders, structural engineer Arup’s solution was a 550mm-deep slab on 1.7m-deep, tapered transfer beams across the engineering hall. Spherical recycled-plastic void formers were used to reduce the self-weight where appropriate. The seven exposed beams were created using a bespoke steel shutter. For the rest of the structure, the contractor used resin-faced standard plywood reusable formwork. The design team created a larger regular grid of joints with the help of chamfered recess battens.

Where the speed of programme permitted, areas such as the reinforced foundations and upper floors include GGBS to lower the embodied carbon. But no pigments were added to the concrete anywhere in the building – the architects preferred the natural concrete patina, which acts as a foil to the areas of white plaster. “We quite enjoy the direct cast quality of the concrete – sometimes concrete can be so carefully done that it looks too homogeneous,” says Langmuir.

Cullinan Studio
Structural engineer Arup
Main contractor Balfour Beatty

Photos: Hufton + Crow