O’donnell + Tuomey’s geometric extension of concrete, timber and light twists and turns to meet a brief from the school, its students and a judging panel of architectural greats

The new extension to the Liverpool School of Architecture started life a little differently to most projects. In 2019, the school launched an invited international competition for a building that would “redefine the nature of architectural education”. The three-stage process would also be an educational opportunity, with students in close dialogue with the architect teams and taking part in the selection process, in a sort of reverse crit. The final round was to be judged by a panel of architectural and design eminences grises, including Kenneth Frampton, Maria Balshaw, Juhani Pallasmaa and Michael Wilford.

The school itself had a long list of demands. It wanted a “flagship project” and “a building respectful of tradition, but ambitious enough to anticipate the architecture to come”. The context was challenging: adjoining the school’s existing 1930s Leverhulme Building and Victorian terrace, but also facing out onto a public square, green space and Frederick Gibberd’s Metropolitan Cathedral. The brief recognised the “lack of cohesion among the parts, a missing public core and social spaces” but stressed the need to retain all of the existing fabric to serve as a narrative history of the school.

At the end of the competition, the last architect standing was Irish practice O’Donnell + Tuomey. Its response was an energetic fusion of angular geometries and long spans, with a folded timber roof structure on top of a “table” of exposed concrete. The upper levels open up into daylit zones for design studios, while a series of overlapping, projecting spaces coalesced around an exhibition hall below. The judges praised the way the design “appropriately celebrated space, structure and light”.

For Willie Carey, director at O’Donnell + Tuomey, it was both a direct, practical solution to the needs of the school and its students, and a spatial response to the various key views and axes. “It was a very unusual situation. There was a geometry established by the location of the cathedral, by the desire to create a new entrance into the school, by the opportunity to connect the 1930s building and 1850s terrace, while both ends of the building address a park.”

The asymmetrical form twists and turns in relation to these constraints, angling away from the Leverhulme Building to open up a wedge-shaped entrance, and cutting back in to face the cathedral. On the north-east corner, the first floor cantilevers out 7m to overlook the proposed university park. Internally, the irregular structure generates a series of dynamic, interconnected spaces, with no two floorplates the same.

Henrik Wolterstorff, associate at O’Donnell + Tuomey, says that it is hard to imagine these spatial sequences being created in any material other than concrete. “A non-concrete building would have to look totally different,” he says. “So we just embraced it, and made sure every bit of concrete worked as hard as it can. There’s no concrete used just for architectural reasons.”

This dovetailed conveniently with another of the project’s aims: as a building where people go to learn about buildings, it was important that both the concrete base and timber roof were structurally legible. “You can see exactly how the structure is working as you walk around,” says Simon Smith, associate director at structural engineer AKT II. The taut frame shows off every sinew. On the first floor, the 300mm slabs are ribbed, with 75mm-deep troughs, saving about 25% volume compared with an equivalent flat slab.

“Where it has to work harder to support the cantilever, you can see it in the change to a flat soffit,” Smith points out. Similarly, the columns have big trapezoidal heads (reminiscent of Denys Lasdun’s IBM Building, page 18), which support the load on the band beams above and allow for a more slender column form below. These column heads are all unique, twisting in response to the building’s various geometries.

With the structure exposed, Smith points out, there are no additional finishes, and therefore no associated embodied carbon. The ribbed slabs also increase the surface area of the concrete, which means more thermal mass – integral to the BREEAM Excellent building’s natural ventilation. And there’s an aesthetic quality to these legible devices, adds Carey. “It gives a character, a kind of energy to the space”

O’Donnell + Tuomey has a long history of using fair-faced concrete, on projects such as the Sean O’Casey Cultural Centre in Dublin and the Saw Swee Hock Student Centre at the London School of Economics. “We’re very serious about how we pour the material, how we finish it. We get into the nuts and bolts of how a wall is made,” says Carey.

At Liverpool, the concrete is light-toned from its 50% GGBS mix, and during the day it is bathed in light from the timber lantern above. While the floors and the tops of the balustrades are polished, the walls have been lightly sandblasted. This changes the way that light is distributed, he says: “On an as-struck wall, you get a lot of reflection, whereas this seems to hold the light and draw it along the wall rather than bounce it back into the space.”

Not that the architects are too precious about their walls. “We wanted to make sure that the building was robust, long lasting and would stand the test of time. These buildings, they’re not laboratories, they’re not lecture spaces, they’re kind of knockabout. But I think you might come back in 100 years and it would still feel the same.” In other words, Liverpool students might have a long wait before they next get the chance to design their own school. 

Interview by Nick Jones

Photos: Nick Kane