Hong Kong soundproofing cases and practical tips - creating a quiet city life
Abstract: Based on facility categories, this article will review and analyze ENA Acoustic's soundproofing engineering cases in Hong Kong government agencies, international hotels, educational institutions, and high-end retail spaces, exploring their acoustic material configurations and application standards. To learn more about soundproofing basics, please refer to Introduction to Acoustic Soundproofing and Sound Insulation.
Table of Contents
- 1. Government Agencies and Infrastructure: Confidentiality and Environmental Noise Control
- 2. Law Enforcement and Immigration Facilities: Acoustic Impedance in High-Security Spaces
- 3. International Star-Rated Hotels: Guest Room Insulation and Floor Vibration Damping
- 4. Educational and Social Welfare Facilities: Reverberation Attenuation and Indoor Air Quality
- 5. Commercial Flagship Stores: Spatial Acoustic Experience Optimization
- 6. References
In 2024, ENA Acoustic designed and constructed soundproofing engineering for the Legislative Council Complex.
In 2023, ENA Acoustic designed and constructed soundproofing engineering for Hong Kong International Airport (T1).
In 2025, ENA Acoustic designed and constructed soundproofing engineering for the Electrical and Mechanical Services Department (EMSD) Headquarters.
1. Government Agencies and Infrastructure: Confidentiality and Environmental Noise Control
Government administrative buildings and large-scale infrastructures have clear regulations regarding Sound Transmission Loss. Acoustic engineering in these venues must simultaneously address the Speech Privacy and confidentiality needs of internal meetings, as well as the low-frequency noise interference generated by the operation of external heavy electro-mechanical equipment[1].
Material and Construction Configurations
In the projects for the Legislative Council Complex and the EMSD Headquarters, the high mass density ENA Soundproof Blanket NE200 was installed inside the walls. According to the Mass Law, this material increases the acoustic impedance of the walls, blocking sound transmission between adjacent offices. For the office areas in the Hong Kong International Airport (T1) terminal, to address the background noise of aircraft takeoffs, landings, and heavy foot traffic, the engineering team deployed ENA Acoustic Cotton (NRC=0.3) on the ceilings and walls to shorten the indoor reverberation time and ensure broadcasting clarity within the space.
In 2026, ENA Acoustic designed and constructed soundproofing engineering for the Immigration Department Headquarters.
In 2024, ENA Acoustic designed and constructed soundproofing engineering for the Castle Peak Bay Immigration Centre.
2. Law Enforcement and Immigration Facilities: Acoustic Impedance in High-Security Spaces
In addition to requiring building materials to be impact-resistant and durable, law enforcement departments and detention facilities also hold sound leakage protection in enclosed states as an acceptance standard. The acoustic planning for the Immigration Department Headquarters and Castle Peak Bay Immigration Centre requires airtightness and silencing treatments for entrances, exits, and ventilation openings.
Airtight Treatment of Structural Gaps
The bottom gap of traditional doors is the primary path for sound diffraction. These projects selected metal soundproof doors with an STC rating of 45 or above. The interior of the doors is filled with rockwool and damping materials, and automatic drop-down airtight rubber seals are installed around and at the bottom of the door frames. When the door closes, it forms a complete physical barrier to prevent the leakage of sensitive verbal information.
In 2025, ENA Acoustic designed and constructed soundproofing engineering for the Mandarin Oriental Hotel.
In 2023, ENA Acoustic designed and constructed soundproofing engineering for The Ritz-Carlton HK.
3. International Star-Rated Hotels: Guest Room Insulation and Floor Vibration Damping
The indoor acoustic standards (NC Criteria) for high-end hotels require the background noise in guest rooms to be maintained below 30-35 decibels[2]. Both the Mandarin Oriental Hotel and The Ritz-Carlton HK are located in Hong Kong's transportation hubs, requiring simultaneous treatment of traffic noise from the exterior walls and structure-borne sound from internal floor slabs.
Comprehensive Acoustic Intervention Solutions
To address external noise transmitted through glass curtain walls, soundproof curtains with mass layers were installed in the guest room window areas to assist in attenuating high-frequency sound waves; to handle floor slab vibrations and footsteps, shock-absorbing soundproof blankets were laid within the floor interlayers. Furthermore, guest room doors were replaced with soundproof wooden doors featuring airtight structures to reduce the infiltration of corridor background noise. (See School and Hotel Soundproofing for details)
In 2026, ENA Acoustic designed and constructed soundproofing engineering for Hong Kong International School.
In 2024, ENA Acoustic designed and constructed soundproofing engineering for Hong Kong Design Institute.
In 2025, ENA Acoustic designed and constructed soundproofing engineering for the Po Leung Kuk Headquarters.
4. Educational and Social Welfare Facilities: Reverberation Attenuation and Indoor Air Quality
For school classrooms, lecture halls, and activity spaces in social welfare institutions, the primary consideration is the Speech Transmission Index (STI). Excessive echoes within the space can degrade teaching quality. Concurrently, the fire and chemical safety of building materials is subject to the strictest standards in such spaces.
Application of Non-Toxic Sound-Absorbing Materials
In the cases of Hong Kong International School, Hong Kong Design Institute, and Po Leung Kuk Headquarters, indoor acoustic treatments primarily utilized large areas of porous polyester fiber acoustic cotton. This material converts the kinetic energy of sound waves contacting the walls, shortening the indoor reverberation time. The selected materials all pass the BS-476-6 fire safety standards and hold Super E0 formaldehyde emission certifications, ensuring the respiratory health of students and users in enclosed, air-conditioned environments. (See Soundproofing Materials Guide for details)
In 2023, ENA Acoustic designed and constructed soundproofing engineering for the Dior Hong Kong Flagship Store.
In 2026, ENA Acoustic designed and constructed soundproofing engineering for the Cartier Hong Kong Flagship Store.
5. Commercial Flagship Stores: Spatial Acoustic Experience Optimization
The interior design of high-end boutique retail spaces needs to consider environmental psychology. Excessively high environmental background noise or air conditioning equipment operating sounds will interfere with consumers' shopping experiences and communication with service staff.
Concealed Acoustic Structures
In the projects for the Dior and Cartier Hong Kong Flagship Stores, acoustic materials needed to function without compromising the brands' interior design styles. The engineering team configured materials with high noise reduction coefficients behind decorative ceiling panels and within wall ventilation gaps. This concealed acoustic intervention effectively absorbs the clamor generated by indoor foot traffic while maintaining visual aesthetics, establishing a tranquil space that aligns with the brand positioning. (See Commercial Soundproofing: Offices and Restaurants for details)
6. References
[1] Long, M. (2014). Architectural Acoustics (2nd ed.). Academic Press. (Acoustic design criteria for government and high-security facilities).
[2] ASHRAE. (2019). ASHRAE Handbook—HVAC Applications. Chapter 48: Noise and Vibration Control. (Background noise criteria and NC standards for hotels and commercial spaces).
[3] Bradley, J. S. (1986). Speech intelligibility studies in classrooms. Journal of the Acoustical Society of America, 80(3), 846-854. (Impact of reverberation time and STI in educational environments).
© 2026 [Ivan Yip, ENA Acoustic]. All Rights Reserved.