Skip to main content



Innovative Noise Mitigation

As the developable land for housing development is very limited in Hong Kong, it is unavoidable that many potential housing sites are situated close to major roads and/or railways. Special designs of building envelope, which are capable of effectively reducing noise entering into the residential units and allowing sufficient natural ventilation at the same time, have been delved and put in use in newly developed housing developments.  

why INMD 1
why INMD 2
why INMD 4
why INMD 3


The acoustic window is unique in allowing for both noise reduction and ventilation. It has two layers – the outer layer is a conventional side-hung window with a push-pull opening, while the inner layer is a half-sized sliding window. By positioning the two layers properly, noise from outside can be muffled while providing natural ventilation for the flat. Enhanced Acoustic Balcony is a specially designed balcony which adopts a combination of mitigation features for the purpose of noise reduction, it incorporates more noise reduction features, e.g. full-height side wall(s), increased solid parapet height, additional screen wall(s), micro-perforated absorber (MPA) and/or additional Sound Absorptive Material (SAM) on more surfaces. This webpage outlines these special noise mitigation designs of acoustic windows and enhanced acoustic balconies and shares the latest development of their application.

Traffic Noise in HK

Planning Solutions

Residential buildings are built close to roads and hence no enough separation distance to serve as noise buffer. Even worse, because of change of economic pattern and also need to find lands for housing, factory buildings which were used to screen traffic noise for residential buildings behind have to be redeveloped as residential buildings, this undoubtedly creates new traffic noise problems if not planned properly. 

You may notice back in 2000, the population exposed to excessive traffic noise was more than 1.1 million. This is because many of the residential buildings constructed in the early days lacked proper noise planning. However, the figure has gone down to less than 0.9M as at 2015, despite the continuous increase in roads, vehicles and overall population. This is because of the noise planning work of EPD and more importantly your support and effort in realizing our strategies against environmental noise.

Traffic Noise in HK 1
Traffic Noise in HK 2
Traffic Noise in HK 4

Noise reduction measures

The Innovative Noise Mitigation Design (INMD) like acoustic windows (AW) and enhanced acoustic balconies (EAB) are the “think out-of-box” solutions providing high degree of noise reduction and at the same time allowing natural ventilation.  The open window living environment offered by such innovative designs is a preferred form of sustainable living over the last-resort of provision of window insulation and air-conditioning.

Traffic Noise in HK 3

Conventional measures


Noise Problem

The housing demand is huge and ever-growing. Under shortage of land, new housing developments are planned closer to busy roads.

Planning Against Noise

Conventional noise mitigation measures gradually become not effective enough. This imposes greater challenge to our noise planning work.

Innovative Measures

Innovative Noise Mitigation Designs and Measures (INMD) are needed to tackle the noise planning problem.

INMD Development

Scale Model Test
Mock-up Test
Completion of King Tai Court
Wide Application
Research on application in private industry
Development Adopted
People Benefitted