The high performance Kinetics RIM-C (Rollout Isolation Material) system from CMS Vibration Solutions has been used to isolate a rooftop plant room at the new civil justice centre in Bristol, preventing machine-induced vibrations from propagating into the building and noise sensitive spaces.

Developed by Miller Construction, the new build civil justice centre comprises of eight civil courts, six hearing rooms and one family proceeding room. A six storey building, the plant room housing all associated equipment to service the centre, including chillers, pumps and air conditioning units, was situated on the roof. Effective isolation of the area was essential to stop the vibrations from becoming structural noise and travelling into the building, which could potentially have caused interference with court proceedings and intelligibility of evidence.

Kinetics RIM-C was specified by acoustic consultants, Deane Austin Associates, to deliver complete isolation of the plant room floor concrete slab. Offering excellent impact and airborne noise ratings, the system achieves its performance by ‘floating’ the concrete floor slab and creating an air void between it and the sub structure. At Bristol Civil Justice Centre, a 100mm air void was a critical factor in the system design, which achieved a natural frequency of 14Hz on-site.

The Kinetics RIM-C system was used to isolate a total area of 137m2. The system was constructed by first laying the Kinetics Isolation Pads (KIPs) in fibreglass matting at 600mm centres and flanking the area with Perimeter Isolation Board (PIB). The critical 100mm air void was subsequently created by installing a C-section channel and timber batten. Finally, plywood and a damp proof membrane were used to cover the area before the concrete slab was cast on top.

As a pre-compressed fibreglass isolator, it is the KIP component of the system which enables Kinetics RIM-C to maintain a constant natural frequency over a wide range of static and dynamic loads. Moreover, there is no appreciable degradation in the isolation performance during the projected lifetime of the floor.

Jim Herbert, technical sales manager, CMS Vibrations, concluded: “With access to the broadest range of anti-vibration and structural isolation systems on the market, we are able to provide the most cost effective and high performing solution to any vibration challenge – backed up by unrivalled technical support. In the case of Bristol Civil Justice Centre, we were able to offer detailed design guidance and see this through to installation.”

CMS Vibrations is the exclusive supply partner of the Regupol RAV and Kinetics Noise Control ranges in the UK.

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