The O2 case study
O2 Arena sounds good with Rockwool
Architect: HOK sport architecture
Main contractor: Sir Robert McAlpine
Engineering and installation: WWR Group Ltd
The acoustically engineered roof of Europe’s largest purpose built music venue, the O2 arena, has been insulated using Rockwool 4 in 1 high performance mineral wool insulation. The roof was designed by specialist WWR Group Ltd, which worked with Rockwool’s technical team from the outset of the project to ensure near perfect acoustics inside the arena with virtually no sound escaping outside.
The design of the O2 arena’s roof incorporates state-of-the-art acoustic engineering to eliminate virtually all nuisance ambient noise (bass thumping) outside the arena while ensuring as near perfect acoustics as possible inside the structure. This means that local residents and visitors to the surrounding shops and leisure complex will not be disturbed by events in the arena.
The complex roof design features several layers of different density barrier materials to deaden even the lowest bass frequencies, which is carried on special acoustic deck structures.
Gary Creaser, managing director of WWR Group Ltd, explained: “The 4,500 tonne roof of the arena, with its pioneering acoustic barrier construction, had to be built up at ground level and then jacked into place, four metres under the existing fabric roof.”
“We worked with Rockwool right from the design stage of the project to model the structure to meet the architect’s specifications. A mix of different Rockwool acoustic insulation products has been used within the roof design to cover a wide audible frequency range and achieve optimum levels of acoustic performance.”
Fully perforated aluminium acoustic trays were filled with Rockwool RW6 insulation, cut to profile and faced with black tissue and supported on 200mm Rigidal structural deck. The structural deck troughs were filled with Rockwool RW4 insulation, with Rockwool Acoustic membrane over and a 50mm Rigidal intermediate deck.
150mm of Rockwool Dual Density HardRock insulation board, in two layers, was used to provide the main insulation, which was overlaid with a Sarna UK Ltd separation fleece and PVC roof membrane.
The compound curve of the perimeter of the roof was then completed with 5m diameter aluminium faced composite panels from Euroclad, which was fixed to a secondary frame. Structural integrity during and after the lift was ensured with SFS intec fasteners.
The 15,000m2 domed roof has a 650m perimeter with a saddle shape to create an undulating roof line. After the two stage lift on the four end towers, the O2 arena roof finished four metres below the PTFE-coated glass fibre fabric of the O2 domed roof.
As well as music, the O2 arena will host the 2012 Olympic basketball and other events, and is the first London Olympics structure to be completed.
