A Mace-led team has turned the north end of Senate House into a light-filled learning space and glazed courtyard for the School of Oriental and African Studies
In these space-constrained times it is hard to believe that the northern end of London University’s most iconic building, the Charles Holden designed Senate House, has been empty for the past five years and, before this, was used as a decant space while other buildings were refurbished.
This was good news for the School of African and Oriental Studies (SOAS), which needed space to expand and improve student facilities. It has taken over the north block of Senate House, which consists of 7,000sq m of space over five floors arranged around a large, central lightwell. While additional accommodation in such an architecturally significant building was welcome, the downside was that the spaces weren’t large enough for the type of informal learning so liked by students - convivial areas where they can discuss issues raised in a lecture, and get some food and drink too.
The north block did have a potentially suitable space, that large central lightwell or courtyard. But this was open to the elements and the building’s grade II* listing made significant change difficult. This challenge was exacerbated by the need to get all of the work finished in time for SOAS’s centenary celebrations this autumn. “Time was absolutely critical,” says Mike Shaw, head of design at Mace. “We had to do this without mucking up one of the most significant historical buildings in Bloomsbury.”
Shaw is part of the team that won the competition to refurbish the north block for SOAS. The team includes conservation architectural specialist Donald Insall Associates and architect Rock Townsend. Unusually Mace wasn’t the contractor on this project, instead it acted as project manager and joint design lead with Rock Townsend (see box, below).
Client Keith Jennings, the SOAS project manager, says the team was selected because of their approach to the job. “The competition was more about a method of solving the problem rather than presenting a design solution,” he says. “Because of the challenges going forward, it was probably the architecture and the heritage elements that sealed the deal.”
The obvious answer was to glaze over the courtyard and use this for the informal learning and social space. But English Heritage considered the internal elevations of the courtyard to be as historically significant as the building exterior and the building’s natural ventilation relies on air passing out through the courtyard-facing windows, which ruled out a glazed roof at high level.
A low-level roof, on the other hand, would prove easier to get past English Heritage and, Shaw says, would also provide a better quality space for students. “The key was the relationship between the people and the spaces, so we knew we didn’t want a massive atrium. We wanted a place that people would occupy, a place where people would go, rather than a space that people would say was really nice but not want to spend any time inside.” This was a key issue for Jennings: “If we are going to spend £1 million on a roof we want more than a courtyard café and a load of chairs.”
The key to unlocking the scheme was to dig out the centre of the courtyard to basement level to provide a double-height space with a glazed roof at the first floor. “We went through a lot of iterations on the type and height of roof,” explains Mark Gabbey, director at Rock Townsend. “As soon as we decided to go down it made life a lot easier.”
The basement was less sensitive architecturally so could be easily adapted for uses including a kitchen and offices. By excavating the centre of the courtyard, it would also allow nobstructed views of the elevations above from the basement, and this area would be used for a café and food servery. At ground-floor level, there would be a perimeter balcony to allow views down into the café and improve circulation through the building. A set of “social steps” would link the basement and ground floor, and provide plenty of seating too.
The roof structure has been minimised to enhance views of the courtyard elevations above. The structure has been pulled away from the walls and consists of eight columns that double up as supports for the perimeter ground-floor balcony. A short, 3m-wide span of glazing connects the wall to the primary roof beams supported on the columns. These beams include concealed rainwater drainage, enabling the perimeter glazing to slope away from the wall leaving a simple flashing detail and minimal support at the roof-wall junction.
The roof area enclosed by the primary structure is double-curved so it acts as a shell structure and cuts own on the amount of support needed. The curved primary roof beams are steel and the secondary beams are laminated glass to increase transparency. The roof glazing panels are double-curved rather than facetted and are triple-glazed.
Shaw says there were only three specialist glazing contractors in Europe capable of taking on such a complex task. The Spanish firm Inasus had the right skills - Shaw says some of its people worked on Foster + Partners’ British Museum Great Court roof in 2000. They were brought in early to contribute to the design of the roof. This central area of glazing steps up from the perimeter glazing like a hat, leaving a narrow strip of vertical glass separating the two elements. This includes opening lights to draw air through the basement rooms around the perimeter of the building and up through the lightwell.
Realising this vision has been a challenge, as it involved excavating the equivalent of two Olympic swimming pools of spoil from the centre of the building and removing it through a window. The job was made more difficult as the contractor who built Senate House had left the foundations used for the crane under the courtyard because money was so tight in the late 1930s. The foundations consisted of four, 5m square blocks of concrete which had to be chipped out and the spoil taken out through the window on a conveyor belt. Demolition specialist McGee did these enabling works but the main contract, which included refurbishing the whole building, was carried out by Graham Construction.
Students will get a good view of the internal elevations from the café through the roof although, inevitably, this is tempered by the internal structure and ground-floor balconies. This roof doesn’t have the elegance and structural simplicity of Foster’s diagrid roof capping the British Museum’s Great Court. But go above ground level and the perspective changes - the flush silicone joints of the double-curved glass panels combine to give a sculptural elegance to the building.
The space under the roof is set to become the new focal point of SOAS and client Jennings thinks £1 million for the roof was an excellent price: “It is the best value bit of the building for what it will bring to SOAS.”
How Mace helped a small architect win a big job
The project was won in competition by Mace, Rock Townsend and Donald Insall Associates. Keith Jennings, the SOAS project manager says this triumvirate worked well, with Mace bringing engineering and logistics skills, Rock Townsend bringing higher education experience - specifically on the University of Westminster’s Marylebone Learning Platform project – and Donald Insall contributing the crucial heritage knowledge. Mace also acted as architect.
Mace’s Mike Shaw says the arrangement enabled an SME with 22 architects to take on an extremely complex job. “Rock Townsend just weren’t big enough to do it on their own.” One key benefit was that Shaw had access to a whole team of experts, including the construction logistics team who could quickly advise on the viability of excavating the basement - a complex and difficult job that was the key to unlocking this project. Mace also had access to highly specialised glass contractors who could contribute their expertise to the design solution.
Both Shaw and Rock Townsend’s Gabbey are keen to stress the collaborative nature of the working relationship - two of Rock Townsend’s architects were embedded within Mace during the design brief stage, with a Mace architect working in Rock Townsend’s office during the concept design stage. Both teams shared a common Revit model. “It wasn’t like a normal subconsultant relationship, because Mace contributed to the design process rather than managing it from the outside,” says Gabbey. “So unlike their traditional project teams, where they are project manager but not designer, it has felt like a genuine collaboration.”
Graham Construction won the job as a design-and-build contract - SOAS retained Rock Townsend as client representative to ensure the vision and design quality were maintained through to completion.
Client: School of Oriental and African Studies
Project manager: Mace
Architects: Mace, Rock Townsend
Heritage consultant: Donald Insall Associates
Structural/MEP engineer: Mace
Construction logistics/sustainability consultant: Mace
Cladding consultant: Wintech/Interface
Lighting consultant: Nulty lighting
Contractor: Graham Construction
Glazing specialist: Inasus