Acoustic ventilation delivers fresh air without the noise

Noise problems for a residential/commercial development in Wimbledon on a site bounded by three main roads and the main railway line to London’s Waterloo Station have been addressed by a Passivent AV (assisted-ventilation) system with acoustically treated ducting and Passivent Fresh 80 dB acoustic wall inlets. The mixed-use development comprises a doctors’ surgery, 37 apartments and offices in four blocks. All the dwellings include the Passivent system. Noise levels on parts of the site were rated category D, but were only 1 dB above category C. Using Passive AV and Fresh acoustic inlets enabled the dwellings to be ventilated without detriment to the sound-insulation levels required by planning consent. Daytime targets of 40 dB to living rooms and bedrooms and the night-time target of 33 dB in bedrooms have been bettered. The AV system installed consists of boostable humidity-sensitive extracts in the bathrooms and en-suite facilities. They control ventilation automatically and have a manually operated boost over-ride. Strategically located acoustic Fresh wall inlets provide sound-attenuated replacement fresh air. The AV whole-house system is BBA certified to meet Building Regulations with inlets as small as 4000 mm2 per habitable room, compared to the 8000 mm2 specified in Approved Document F1. The system eliminates the need for separate acoustic boxes and ensures constant background trickle ventilation without draughts. Assistance is provided by a low-wattage fans, and there are few moving parts.

Related links:

• www.passivent.com