In creating a landmark building for a West Midlands college, D5 Architects had to come up with problem-solving ideas to link the 1960s block next door.
When North East Worcestershire College decided it was time to revamp its campus in Redditch,
it was keen to stamp its identity on the town. The buildings making up the campus were a hotchpotch of uninspiring structures dating largely from the 1960s. Esentially, they were a blot on the townscape, and the college wanted to replace them with a landmark building that would attract the local community.
Birmingham practice D5 Architects was given the task of designing a learning and resource centre, but the tight budget meant that a really eye-catching design would be tricky. What is more, D5 had to retain a dull three-storey building opposite the campus building.
D5, however, had a bright idea that was cost-effective and striking to look at. It decided to link the new building and the uninspiring block with an enormous bow-truss steel and glass roof. The visual impact of such a large roof spanning the space between two relatively small buildings is dramatic. The fact that the resulting plaza is open to the elements at one end gives even more emphasis to the soaring sense of space.
The roof is in the shape of a shallow asymmetric V, rather like a tick. The aluminium frame supporting the glass is in turn supported by steel columns positioned at the angle of the tick, and five large steel bow trusses.
At the north-west end is a restaurant, which bridges the space on the second and third floors and provides an internal circulation route between the two buildings.
A covered square was not in the brief but Ben Jepson, associate architect at D5, says that once the college saw the concept it was keen for it to be built. Jepson was able to push for a decent specification so he stipulated glass over cheaper alternatives such as polycarbonate or Teflon.
“Glass was such a fundamental part of the scheme, that it could not be compromised,” says Jepson. He says that Teflon would have diffused too much light, and polycarbonate would have presented the college with maintenance issues as it has a tendency to attract dirt.
The lopsided tick shape came about because of the need to limit the span of the roof. “If the span was any wider then the steel elements would have been deeper and chunkier,” says Jepson. The use of bow trusses also meant that the thickness of the steel could be minimised. “It was the slenderest option.”
As well as providing an unusually shaped roof, the pitch of the smaller span also has a practical function – to clear rainwater from the flat roof of the old building. The rainwater collects in the gulley between the two roof sections and is taken off the roof via a siphonic rainwater drainage system from Geberit.
The impressive roof will make the students feel good about their college. Townspeople should also take pride in their covered plaza. The space is currently popular with skateboarders, who make the most of the steps and handrails, but once there is seating in place the square should become a popular stop-off point for shoppers on their way back from the high street.
- For more details on the roof of the new building, see “Appraising the roof”
Appraising the roofConsidering that its form is essentially rectangular, the learning and resource centre at North West Worcestershire College boasts a lot of unusual geometry.
This is in part due to the number of different roof types. A Kalzip barrel roof on the second floor of the three-storey building, for example, gives the north-western facade an unexpected twist. It was specified partly for planning reasons. The council was wary of a nearby Victorian terrace being outmuscled by chunky architecture. To reduce the impact D5 specified a barrel-vaulted roof on the second floor. “The barrel was a graceful solution and it means that the scale of the building drops down towards the houses,” says Jepson.
Jepson said that he specified a standing-seam steel roof because it was going to be highly visible from the street: “Because it can be seen, we wanted a more stylish roof,” he says. “A straight monopitch would have been cheaper but we coaxed the client round.” Jepson was told that because of the tight radius of the barrel he would not be able to specify a smooth steel ceiling liner. Instead it was crimped, which gives the impression of a chocolate bar in its foil wrapper.
There is another curved roof at the north-western corner of the site, where the kitchens, service rooms and a nursery are located. This is a sloping trapezoidal roof, which curls over the edge of the nursery roof to form the building wall.
The other roof worthy of note is a terrace, which is accessed from the first-floor restaurant.
D5 wanted the timber decking to match the cedar cladding of the single storey building, but cedar is not hardwearing. Instead, D5 specified timber decking using the hardwood bankirai, which is a suitable match for the cedar.
SuppliersStanding seam aluminium roof Corus Kalzip www.kalzip.co.uk
Profile metal roofs Armstrong Ceiling
Single ply roof membrane Sarna www.sarnafil.co.uk
Syphonic drainage Geberit www.geberit.co.uk
North East Worcestershire College