CableNet was initially specified by the project architects John McAslan and Partners as the safest and most flexible way of providing access to the high level technical space. This contains rigging, lighting and audio equipment above the stage and auditorium.
Slingco was initially consulted in 2002, and CableNet was an integral part of the rebuilding plans very early in the design process. They liaised with other civil and engineering contractors to co-ordinate the design, and ensure a smooth and efficient installation.
Circular tension wire grids are rare. Slingco's first UK model was completed at Brighton Dome in 1998/99, and more recently, they designed a horseshoe shaped grid for the Hampstead Theatre, just up the road from the Roundhouse.
Slingco jumped at the challenge of being involved at this historically significant venue. Slingco's Nick Dykins says: "The Roundhouse has a real rock n' roll past and is an outstanding venue - we are delighted to be part of its revival. The CableNet installation for this project is awesome - doughnut shaped with no intermediate supports - riggers will love it!"
The most exacting engineering element of the project was ensuring that the inner and outer ring beams up in the roof were strong enough to absorb the tension loadings of the cable assemblies, and designing them to be robust enough to suspend the grid frame from tie bars connected to the roof support structure.
The grid's frame has no support struts between its inner and outer frames - it is all woven in 4mm diameter wire. The outside diameter ring beam measures 14.3 metres and the inside is three metres in diameter, giving a total grid area of 147 square metres.
Slingco's Peter Downham-Clarke co-ordinated the project on site with design project manager Simon Down. Down comments that it has been an excellent experience working with Slingco who have always been "conscientious and meticulous in their attention to detail".
The tension wire grid frame was assembled on the Roundhouse floor and lifted into its final location using nine 1.5 tonne chain blocks - in a delicate operation overseen by the Slingco installation team. It took a day to lift and fix the grid into its final position at its full height of 12 metres. This was a really tricky process as the grid needed to be picked up and raised, millimetre perfect, in exactly the right position in relation to the support steelwork and pre-positioned hanger locations. Alignment was achieved using plumb lines, probably the same methodology that the Victorians would have used.
Originally built in 1847 as a steam engine turning shed, when the locos outgrew the venue, the Roundhouse became a Gilbey's Gin warehouse from 1860 - 1960 after which it had its first taste of being an arts centre. It became legendary in the 1960s and 70's when all the top bands played there including the Rolling Stones and Jimi Hendrix. It closed in 1983 and was used only intermittently, falling into greater dereliction. In 1998, The Roundhouse Trust was set up to manage restoration the extraordinary space, putting it back at the centre of London's innovative and experimental cultural heritage. The new venue will accommodate 3300 standing and 1700 seated. At its heart will be a unique creative centre for young people - Roundhouse Studios. Featuring state-of-the-art facilities for music, TV radio, new media and design and performance production, the Studios can cater for up to 10,000 young people, specially those with little or no access to arts education.
(Chris Henry)
