Project review

Project
Interdisciplinary nanoscience research centre for University of Cambridge

Location
West Cambridge campus

Design features

• Laboratories for research into microscopic particles engineered to provide ultra-clean environments with almost no vibrations
  
• Site layout, building blocks and landscaped garden designed to provide a user-friendly environments and relief from intense research activities

Procurement features

• Two-stage tendering ensured early integration of design and construction teams
  
• ECC contract encouraged mutual trust and co-operation

Cost features

• Unit cost of £2809/m² below average benchmark cost for higher education laboratories of £3000/m²
  
• Value engineering cut costs by £1.5m, to meet the fixed budget of £5.5m

Development period
Twenty months from RIBA Stage C design to completion

Client's brief

The University of Cambridge is one of the world leaders in nanoscience. Professor Mark Welland and his research unit, which is a joint venture of the university's engineering and physics departments, had outgrown their existing facilities in the city centre and required a larger, purpose-designed building in west Cambridge.

Creating an internal environment with ultra-clean and "vibration-free" conditions was the major challenge for the designers. The laboratories needed to house an expandable clean zone containing four large cleanrooms, where the miniature components, compounds and materials could be created free from extraneous airborne particles. Extreme standards of cleanliness up to class 10 standard were stipulated, which is hundreds of times cleaner than a hospital operating theatre. "Vibration-free" equipment modules, where scientists' creations are studied under electron microscopes, were also specified, along with the range of resonant frequencies that they could operate within. In addition, the brief included general laboratory areas and office and write-up areas.

High-quality social amenities were also considered vital. Both architect and client were keen that, in the pursuit of such high-tech facilities, the idea of creating a humanistic environment was not lost. Natural daylight, natural materials and a landscaping – including aromatic planting – were used to create stimulating and user-friendly surroundings, which would act as a relief from the intense working environment of the cleanrooms.

Architectural design

A site for the proposed Nanoscience Research Centre was selected within the emerging research campus at West Cambridge. West Cambridge is the home of the Cavendish Physics Centre and the William Gates Building. Other science research centres are currently being planned for this site. By bringing together all these facilities in one location, the university hopes to foster interdisciplinary working across traditional boundaries.

The site's gentle southerly slope was favourable. An existing earth bank wraps the colder north side and forms an angled south-facing plane that captures the heat of the sun, and the Cavendish buildings give shelter from the prevailing south-westerly winds.

The architect distilled three distinct elements from the brief – the laboratories, researchers' offices and social pod – and conceived these as a group of three linked single-storey blocks, each with its own form, materials and character. As in a cloister, a glazed ambulatory follows the site contour and links the blocks in a horseshoe formation around a garden, where researchers can relax, contemplate and share ideas while taking a break from the cleanrooms. The ambulatory doubles as a display area for the work of the department. Being set into the site slope at two levels along the northern edge of the site, the buildings capture the sun's heat and shelter the researchers' garden. The main entrance is formed at the upper level by a glazed vestibule that overlooks the garden.

Since completion, the building has won much praise from its users and the wider scientific community, and has been described by the client as "a peach of a building".

Laboratory block
The laboratory block, which houses the four cleanrooms, equipment modules and general laboratory, has been given a distinctive curved roof. Not only does this curving shape suggest that the building has grown out of the landscape, it also provides enough roof space to house the critical air-handling plant directly above the cleanrooms they serve.

The block faces the garden to the south through a long window wall shaded by a wide roof canopy. This window wall gives researchers in each cleanroom a view of the garden and lets passers-by catch glimpses of the work within. Along the northern edge, where the roof is at its lowest, a services spine offers easy access for maintenance and replacement.

Alongside the cleanrooms are equipment modules containing the electron microscopes. They are shielded from external sources of vibration by a complex system of isolation measures culminating in the high-mass concrete bases with neoprene shock absorbers, which are further isolated from the structure of the building.

The general laboratory occupies the remaining space at one end of the block and provides flexible experiment areas and space for expansion of the cleanrooms or equipment modules. An angled gable captures the soft north light and gives the researchers a view of the landscape.

On handover the cleanrooms, installed by specialist contractor CRC, achieved better than the stringent standards laid down in the brief.

Researchers' house
The timber-and-glass researchers' house is conceived as a quiet community of scientists, and a retreat from the environment of the laboratories. Though lower in height than the laboratory block, the house is set on a plateau slightly higher than the laboratories and placed to overlook the researchers' garden. Ranged around the open-plan area, the academics' offices all look out into a walled garden sculpted from the slope. The space under the gently curving roof was designed to be more of a study than an office, providing a calm space for the collaborative consideration of the work carried out in the laboratory. The roof projects to create a canopy over the fully glazed west and south elevations. Its wide timber-clad soffit protects the researchers' patio as well as providing solar shading. A conical rooflight points towards the morning sun, bringing light into the heart of the house.

Social pod
The social pod is a tiny timber-clad tabernacle. It provides a breakout space set within the heart of the garden and opening onto a timber deck. Linked to the laboratory block but facing the researchers' house it completes the triptych of research, practice and creative thought.

Procurement

The procurement strategy had to accommodate the following constraints:

• No flexibility on an extremely tight budget (£5.5m)
  
• Demanding programme (20 months from RIBA stage c design to completion)
  
• Large mechanical and electrical engineering and cleanroom component within the project (approximately 42% by cost)

A strategy was selected with the following features:

• Use of ECC Contract Option A (fixed-price contract with activity schedule), and wholehearted adoption of the "spirit of mutual trust and cooperation" it sought to instill
  
• Two-stage main contractor tendering ensuring early integration of the design and construction teams, and the parallel design and tendering of work packages
  
• Early letting of an enabling contract for "non-design critical" preliminary works, such as archaeological investigation and diversion of existing services
  
• Early integration of a cleanroom design-and-build contractor as consultant within the BDP multidisciplinary design team
  
• The placement of mechanical, electrical and cleanroom installations with a single subcontractor to minimise trade interfaces
  
• Active use of risk management.

Value engineering and risk management
After the first detailed cost estimate exceeded the university's funding allocation, a series of value-engineering workshops successfully identified approximately £1.5m in savings to achieve the contract budget of £5.5m. Approximately half the savings were achieved on the building elements by replacing Sarnafil singly-ply roof membrane with a cheaper Trocal system, reducing the area of external wall glazing, critical evaluation of internal finishings, reconfiguring plant room layout and location and the omission of a bicycle underpass, which would have necessitated excavation and construction of retaining walls. The remaining cost savings were achieved through value engineering of the mechanical, electrical and cleanroom services and components.

Project risks were identified at an early risk workshop and generally successfully mitigated. In particular, early procurement of the glass cladding panels on a long lead-in period helped to prevent an initial delay to the programme. The independent management of all utility service supplies to the building by the university's overall consultant for the West Cambridge campus also proved to be a success.

A serious risk was posed by the stringent requirement that virtually zero vibration should be transmitted to the research equipment. What made this even more difficult to achieve was the large amount of mechanical plant required, the bulk of which was located directly above the cleanrooms on a steel-framed mezzanine floor. Added to that, detailed design of the anti-vibration mountings and the mezzanine plant rooms was split between lead consultant BDP and cleanroom contractor CRC. Accordingly, the procurement strategy recognised that to provide effective anti-vibration characteristics, all work needed to be designed and monitored with a single point of responsibility. BDP's integrated design successfully met this onerous requirement.