Willmott Dixon is playing a central role in the design and build of one of the most advanced and heavily serviced facilities in the country.
Project: National Space Integration Facility (first phase)
Client: Rutherford Appleton Laboratory
Contract value: £21.6m
Contract type: NEC Option A – Design and build
Main contractor: Willmott Dixon
M&E subcontractor: Briggs & Forrester
Start date: November 2013
Completion date: May 2015
Appearances can be deceiving.
It may look like a glass-clad shed from the outside, but this is one of the most hi-tech and heavily serviced buildings imaginable.
The National Space Integration Facility, which Willmott Dixon is building at the Harwell Science Campus in Oxfordshire, will be a world-leading R&D centre, recreating conditions from outer space.
Temperatures in some test chambers will go as low as -260 deg C – almost absolute zero on the Kelvin scale.
Harwell is the nerve centre of the UK’s space industry and home to the Rutherford Appleton Laboratory, which masterminded last year’s Rosetta comet landing and will operate the new facility.
Chiefly it will be used for testing out new instruments for use on future space missions.
Over 40 per cent of the £21.6m build value of the project’s first phase is accounted for by services; no surprise given the nature of the R&D facilities inside the building.
Fag packet sketches
But the real construction story here is Willmott Dixon’s central involvement from day one on such a complex project.
“All we had to work with was a ‘back-of-a-fag-packet’ design – some very basic sketches of what the client wanted”
Noel Cafferty, Willmott Dixon
“The tender came out in October 2013 and we were awarded the design-and-build contract a month later,” says Willmott Dixon project manager Noel Cafferty.
“All we had to work with was a ‘back-of-a-fag-packet’ design – some very basic sketches of what the client wanted, showing layout of the main industrial areas, some desired interdependencies between their operations, and office space bolted on the outside.
“We have had to develop that into a design with our architect FDG, and then price all the work packages – in the space of just six or seven months.
“I should say that this is a very informed client. The programme has been very fast, but they have known exactly what they wanted, and there has been a strong team ethos.”
The design development phase was “intense”, according to Willmott Dixon’s senior design manager Richard Clark.
“Essentially our engagement started at RIBA Stage 1. We had to work very closely with the end user, and flew through each of the first three RIBA Stages on, roughly, a monthly basis.
“RIBA Stage 3 was signed off by the client in early February 2014, and the planning application was made that same month.
“In parallel with the planning process, RIBA Stage 4 detailed design was progressed and submitted for client sign-off early April 2014.”
Meanwhile, the pricing took place. “Once planning consent was granted, a series of early works costs were agreed so that enabling works could begin ahead of the main construction phase,” Mr Clark says.
“A key part of this was supply chain engagement on the key trade packages to enable a prompt start on site.”
During the design development phase, the client decided to split the construction into two phases: 1A, costing £21.6m and including the shell, core, and most building services and research facilities; and 1B, which included further R&D areas plus offices.
Willmott Dixon started construction of phase 1A in June 2014, with a target completion date of May 2015.
The 7,500 sq m building is 17 m high and comprises three storeys, all of varying layouts to accommodate the R&D facilities.
Level one is effectively a mezzanine, with only a partial floor plate. Level two has a full floor plate. Level three is split between plant rooms and the roof, with the M&E plant prefabricated as far as possible to help accelerate the programme.
The two Space Test Chambers on the ground floor, 5 m in diameter and 15 m long, will be full building height when completed.
Giant seismic blocks
To accommodate vibration testing, each STC sits on a 300 tonne concrete seismic block. These are positioned on steel springs, which allow the block to move, ensuring ‘vibration isolation’ in the test chamber.
The blocks are 5 m wide and 15 m long, and T-shaped in cross-section, with the 4 m-deep ‘foot’ of the T running the length of the block. “It acts in similar fashion to the keel of a ship,” Mr Cafferty explains.
Each seismic block sits in a pit, which was formed by Willmott Dixon, but the concrete blocks were designed and cast in situ by RAL’s specialist contractor PES.
Willmott Dixon has also had to manage another RAL contractor – CRC – during construction of the clean rooms, which cover 1,200 sq m. The package value is £3.4m, of which more than a third is services.
A big challenge for Mr Cafferty was managing the interface between CRC and Willmott Dixon’s own M&E contractor, Briggs & Forrester.
The latter’s work package is worth £6.7m, and the firm acted as services designer, so is a key player on the project.
“Understanding how the services interfaced was important,” Mr Cafferty explains.
“CRC also carries out services installation as part of its contract, and the big issue was determining who does what. Essentially, CRC is responsible for all of the clean rooms and Briggs & Forrester does the connections.”
Mr Cafferty’s CV includes previous work on science faculties at the University of Cambridge, also heavily serviced buildings, and the experience gave him an “understanding of how to manage lots of different M&E elements and their contractors”, he says.
Other test facilities in the new Harwell building include Small Vacuum Chamber suites and another vibration testing area to replicate take-off conditions.
“The steelwork is quite complex. There are 13 high-level gantry cranes which have to be fitted to structural steel beams”
Noel Cafferty, Willmott Dixon
The facility will also house the UK Centre for Calibration of Satellite Instrumentation.
The construction programme has been shaped by the lengthy design development [see box].
“Besides the building services, the steelwork is quite complex,” Mr Cafferty says.
“There are 13 high-level gantry cranes which have to be fitted to structural steel beams, and we had to plan the construction sequence so that these cranes could be installed during the steel erection.”
Outer space theme
The exterior design of the building has been influenced by what Mr Cafferty describes as an “outer space theme”. “They are fond of using dark blue and gold,” he says.
The south and east elevations of the facility – essentially the front, where the reception atrium will be located – feature metal rainscreen cladding and curtain walling, with a brise soleil.
On level three, there is ‘desert gold’ coloured cladding, which was originally intended to drop down through the other levels, behind the curtain walling.
“Budget constraints mean we’ll be using ‘desert gold’ paint instead on the internal walls to create the same effect,” Mr Cafferty says.
The north and west elevations – the rear of the building – use Kingspan composite cladding and louvres around the M&E plant area.
The Space Integration Facility has been designed to achieve a Very Good BREEAM rating. But in some ways that is incidental, given the running costs of the building.
“They will have annual energy bills of £8m,” Mr Cafferty says.
This phase of the project is scheduled to finish in May.
“The design development was completed for the whole building, but the client wants to revise it to get more out of phase 1B,” Mr Cafferty says.
That phase should begin in June 2015.
The BIM plan
To plan the steelwork – not to mention the numerous service runs – Willmott Dixon has used building information modelling.
“We produced and shared Revit models throughout the design process,” Mr Clark says. “This enabled key areas of design co-ordination to be considered early in the process, such as between the structural steelwork, overhead gantry craneage and M&E services.
“It also enabled the end-users to consider earlier on how some of their specialist equipment would satisfactorily be co-ordinated with, and installed into, the building post-completion.
“Clash detection exercises were run on the developing models, and elements of the design were adjusted to eliminate clashes which might not otherwise have been spotted in time and to therefore suit the fast-track procurement and installation programme.”
The process has operated at BIM Level 2, though the next phase of the project may extend use of BIM further, Mr Clark adds: “The client wants to add detail such as locations of the sockets, for example.”
Mr Cafferty says that the steel contractor, Morgans of Usk, was “excellent” in responding to a demanding programme.
“They were erecting the steelwork just a month after we had started on site and it was very much a hand-to-mouth process,” he says.