External Fašade Sound Insulation and Passive Ventilation

Ken McGunnigle

New Zealand Acoustics, 16(2), pp.8- 13 . (2003).

External noise from road traffic, airports and industry is becoming more problematic. Consumers have changing and increasing expectations of the amenity value and acoustic quality in their homes. Greater demands are put on what we require from the space inside a home and the sustainability of the consumable resources. In New Zealand activities in the environment are under the legal jurisdiction of the Resource Management Act 1991, including noise pollution. In order to obtain a Resource Consent the territorial authority may require the construction of a new dwelling to be sufficiently sound insulated to provide a prescribed sound level (often 35dBA at night) within the habitable spaces. In most noisy locations this normally requires the windows to be closed and for mechanical ventilation to be provided. This paper examines an alternative approach, which unlike mechanical ventilation has a low initial capital cost and does not consume electrical power throughout the serviceable life of the building. A passive ventilation system is tested on site for sound insulation and compared to open and closed windows. It was found that passive vents provide adequate sound insulation together with some permanent ventilation of the space. The current New Zealand Building Code requirements of Clause G4 for Ventilation are considered and compared to what would be needed in order for passive vents to be developed as an alternative solution for the building code. A multidisciplinary approach is required to deliver a practical solution and a scope of the research work to achieve this goal is set out.