Jack Harvie-Clark Acoustic challenges and solutions for dwellings - PowerPoint PPT Presentation

Jack Harvie-Clark Acoustic challenges and solutions for dwellings DESIGN. DELIVER.PERFORM. www.cibse.org/Build2PerformLive

What’s the problem? 7 m people “seriously annoyed” 4.2 m exposed to dangerous noise levels at night 2 nd highest environmental burden of disease

Façade mitigation: current state of the industry 85 % of planning applications assumed: Windows open - for overheating assessment Windows closed - for noise assessment Using planning conditions to improve indoor environmental quality IEQ in new residential developments N Conlan, J Harvie-Clark, Apex Acoustics Ltd. Proc. IOA Vol. 40. Pt. 1. 2018

ProPG Where … internal noise levels can only be practically achieved with windows closed … provide good standards of acoustics, ventilation and thermal comfort

“Regulatory design tool” Internal noise level Lowest observable No adverse effect Duration for mitigating overheating

Options for attenuated natural ventilation Standard windows Attenuated windows Balconies Attenuated vents 5 10 15 20 25 30 35 Level difference from outside to inside (dB)

Plenum windows - vertical www.apexacoustics.co.uk/open-windows-good-sound-insulation/

Plenum windows - horizontal Tackling Traffic Noise Through Plenum Windows – An Application in Hong Kong, M Yeung et al, Internoise 2014, Melbourne, Australia

Window with attenuator www.apexacoustics.co.uk/open-windows-good-sound-insulation/

Balconies to mitigate façade noise Methods of controlling noise levels and overheating in residential buildings. N Conlan, J Harvie-Clark, 24 th Int. Congress on Sound & Vibration, 2017, London

Balconies to mitigate façade noise Case Study of Design for Noise Mitigation Measures for Public Housing Developments in Hong Kong, Sustainable Building 2013, Hong Kong Regional Conference

Attenuated vents: St John’s Hill, Clapham Level difference - 27 dB Free area - 0.4 m 2

Attenuated vents: NW Cambridge Level difference - 29 dB Free area - 0.25 m 2

Attenuated vents: NW Cambridge

Attenuated vents: 26 storey refurb, London Level difference ~ 37 dB Free area - 0.12 m 2 Fan boost – 90 ltrs/sec Image courtesy of TEK Ltd

Attenuated vents: student flats, Cambridge Fan boost – 94 ltrs/sec Level difference - 24 dB Images courtesy of TEK Ltd

Certainties … … and uncertainties Success : sustainable, resilient, comfortable Thermal performance Need for early concept Regulatory driver is coming! Occupant experience Failure : mech cooling / uncomfortable Developer response Occupants should not be forced to choose between thermal discomfort and adverse health impacts from noise

Jack Harvie-Clark jhc@apexacoustics.co.uk @JackH_C www.apexacoustics.co.uk/noise-ventilation-and-overheating-in-dwellings …/ attenuated-passive-ventilation-options www.cibse.org/Build2PerformLive