Kalzip helps to achieve the three “L”s at the 02 Dome
HOK sport architecture specified Kalzip standing seam on the 02 Dome for the three Ls – low-maintenance, longevity and ability to limbo! The practice used two types of Kalzip – standard 65/400 sheets and the new XT sheets which can be tapered, curved and twisted in 3D shapes - as well as bespoke flashings to clad the “back of bowl” or level four concourse which runs around the arena. The 2,000m² of straight and tapered standard sheets which were installed by Lakesmere above, and in some places level with, the 700m² of XT sheets, had to be twisted to achieve HOK’s design above the level four concourse where the pitch changed by 22º over a length of approximately 45 metres. Taking the use of Kalzip “to a whole new level”, the Dome combined not just its use as a cladding material (rather than the more traditional roofing) but also its use in a horizontal and twisted application. As well as the three Ls, HOK specified Kalzip for its recyclability since being aluminium, the sheets can be re-used at the end of a building’s life. HOK’s Brian Ditchburn said the practice had initially looked at sinusoidal sheeting but while this could achieve the flat areas and single curvature, it could not the areas of double curvature. Also, for the joints between the panels to run horizontally, a number of the sheets needed to be banana-shaped when laid out flat. Kalzip’s XT can provide both parallel and tapered upstand sheets to a radius on plan.
Kalzip also works in Rhino (3D modelling software) so once the sub-contract was placed, they were able to take ownership of the model to develop the original offset surface with the Kalzip approved Teamkal sub-contractor Lakesmere and develop the sub-structure to retain the individual sheets in the correct geometry. The lower bowl of the arena is wrapped by four floors of exposed concrete balconies characterised by stairs and escalators seen through a screen of glass suspended from the underside of the upper-level concourse. The upper bowl reads as a separate element clad in Kalzip. The basic premise of the upper bowl cladding was that its construction could be fairly simple as it was a big area that would be seen from a distance. For this reason it is painted a blue/black and lit with blue gel lights so that its mass looms above the concourse. “The design life of the building is so many years and beyond that the materials should be recyclable,” said Brian Ditchburn. “Hopefully, the economic life of the building is longer in which case the aluminium Kalzip sheets should stay in place, needing little maintenance, long into the future.” Lakesmere’s design manager Alan Painter said: “The most complicated aspect was designing the standard Kalzip sheets and sub-structure to create this twisted effect. “The structural steel support also had to be designed and plotted using a 3D model to ascertain the exact coordinates for the positioning of the XT sheets which were also curved and twisted. We took the initiative to calculate the individual curvature of the sheets prior to their installation along the concave of the arena wall. “The 02 arena is a perfect example of the flexibility and quality of the Kalzip product. To meet the architect’s unusual design has taken the use of Kalzip to a whole new level.” The design aside, the logistics on this project were also challenging. As the arena had been constructed within the existing structure of the dome, the work area was very restricted and access points had to be shared with other sub contractors. Plant and materials had first to be craned into position on the fourth floor. Working at this height, mobile access and elevated working platforms were used to hoist and fix the sheets into position.
Given the restricted access and location of the works, communication was vital if the challenge was to be met. To this end, Peter Shields of Sir Robert McAlpine Lakesmere site staff met with the team on a weekly basis to plan and coordinate with other trades, the result of which meant working split shifts and weekends to overcome the logistical problems and meet the tight programme ahead of schedule. Peter Shields said: “I believe the innovative and highly competent design solutions were vital to the overall success of the project. In addition, the team’s can-do attitude, attention to detail and overall enthusiasm and commitment helped to ensure the architect’s design was effectively and accurately realised.”