• Cladding the largest single temporary structure ever created in Olympic history
• Installing 20,000m2 of fabric including 13 roof panels weighing ¾ tonne each and 70 facade panels in just 90 days
• Prototyping each facade panel to ensure the highest quality finish and minimise site delays
• Exemplary health & safety record with zero accidents during the entire build
• Playing our part in reportedly the best Olympic games ever
Sam Wright, Wilkinson Eyre Architects AEG
Alan Howatson, Barr Construction
Tony Witten, Director, Watsons Steel
Neil Holloway, Fenton Holloway
Mark Smith, Head of Projects / Director, Base Structures
Andy Chiverton, Project Manager, Base Structures
When Barr Construction won the tender for the £42million contract to deliver the Basketball Arena in 2009, it was clear that the contractor would need a specialist supplier to fulfil the significant tensile fabric cladding element. Whilst performing a factory tour for the Olympic Development Authority (ODA) and Barr Construction, Base demonstrated its 2000m2 production facility and state of the art machinery supported by 20 fabric manufacturing specialists. Thereafter, Base was appointed to manufacture and install the tensile fabric cladding facade and roof for the basketball arena, the first of many projects that Base would undertake for London 2012.
The Basketball Arena was the third largest venue in the whole Olympic Park and the single largest temporary structure ever built for an Olympic Games. Designed by Sinclair Knight Merz with Wilkinson Eyre Architects and KSS, the plans envisioned a huge steel structure encased in a 3D, geometric shaped fabric form to resemble a giant ice cube. Created and conceived as a temporary structure, given the lack of demand for such basketball facilities after the Games, fabric was an essential element that could take an otherwise utilitarian structure and give it a stunning, aesthetic facade - living up to the required Olympic spectacle. At the same time, fabric is incredibly lightweight, fast to erect and can be demounted just as quickly, satisfying the practical project criteria too.
While the majority of the structural steel scheme design had been completed, Base’ expertise was called on to refine the design detail to ensure that the vision could realistically be built within the constraints of the site, timescale and available budget. The brief was to pattern and fabricate the membrane facade and roof - all 20,000 square meters of it - and install it on site with the highest quality of workmanship, ready to showcase London 2012 to the world.
While Base prides itself on rigorous Health & Safety practice, procedures on the Olympic site were even more challenging than usual, with the ODA setting the target of being the first Olympic Games with zero attributable deaths during the construction process, and achieved it in spite of 62 million hours of work. The Accident Frequency Rate was just 0.17 per 100,000 hours - less than half the construction industry average
Base was working to a set timeline which made no allowance for poor weather conditions. Working at a height of 35m, wind can create problems and this inevitably led to downtime which had to be recovered to achieve the set completion date. The installation element was exceptionally involved with a strict work schedule and predetermined installation methodology to be adhered to, reducing relatively high-risk rope access techniques to a bare minimum. This resulted in extraordinary reliance on MEWPs (Mobile Extending Working Platforms) and eventually the use of two of the biggest scissor lifts in the country to install each ¾ tonne roof panel.
Being a temporary structure, the ability to demount the structure (and remount) without inflicting any damage also had to be factored into the build programme. This led to refinements in the installation approach and details such as the zipping together of fabric weather flaps between adjacent panels to avoid having to slice panels out when deconstructing it.
Finally, the Basketball Arena was sited next to the soil hospital where contaminated soil was cleaned. Inevitably, the gleaming white fabric facade was gradually covered by dirt from the accompanying site - not quite the impression the ODA was keen to project at London 2012!
A great deal of time and effort went into ‘designing out’ installation issues on the factory floor. The facade was made up of a series of three basic 6m X 25m panels and three reverses of these featuring in a random pattern around the facade - 70 panels in total. With each panel being dead fit with no room for adjustment, the team needed to satisfy themselves that all the shapes would work in situ and would be tensioned correctly with no hint of a wrinkle prior to fabrication and dispatch. The manufacturing department and installation team worked together to create no less than five full scale prototypes, each refined a little more than the last, ensuring that they would be able to progress and install the entire facade without having to tension each individual panel on site. A full scale mock-up was also constructed for the gutter / roof panel intersection where it was critical that there was not a single leak, no matter how much water was running of the huge expanse of the roof.
With regards to safety, Base increased its exemplary performance, recording no accidents during the entire build. To ensure the structure was presented gleaming white as it was originally conceived, the team undertook two full cleans, the last just weeks before the opening of the Games. Each clean took 143 man-days to complete, inside and out.
Despite 10 days of poor weather delay, the team pulled out all the stops to meet the required timeline, a process streamlined by the rigorous attention to detail during the design process.
“I’ve worked with Base on several projects now; the Liverpool Arena and the Basketball Arena for the London 2012 Games. Working on high profile projects, you need to know you’re working with the best and most innovative talent in the industry – cue Base Structures. We place great importance on the initial concept designs and form finding and Base has delivered in spades at every opportunity.”
Sam Wright, Wilkinson Eyre Architects
The 20,000 square metre facade and roof were delivered on time and on budget in just 90 days. Overall the Basketball Arena was recorded as the quickest Olympic venue to be built. Its stunning fabric form became one of the most recognised venues of the London 2012 Games and was a centrepiece of a construction line up that boasted more than 25 temporary venues.
During the Games, the Basketball venue welcomed more than 288 athletes competing for two gold medals plus the handball, wheel chair basketball and wheel chair rugby competitors. With capacity for 12,000 spectators, it was one of the most heavily used venues on the Olympic Park.
The Basketball Arena, owned by Barr Construction, went up for sale at a price of £2.5 million.