| Hong Kong Housing Authority and Housing Department

Wah Ha Estate – Accomplishment of Project Team’s Collaboration

The Hong Kong SAR Government announced in 2012 that the dilapidated Chai Wan Factory Estate (CWFE) would be converted into public rental housing, as a short term measure to increase and expedite public housing supply. CWFE was granted Grade II Historic Building status by Antiquities Advisory Board. Wah Ha Estate is the first-ever Hong Kong Housing Authority (HA) public rental housing project converted from a historical building. The estate was completed in 2016, providing 187 domestic flats on five floors with the ground floor designated for commercial, courtyard, display area, car park and estate management facilities.

Tasks to be resolved were enormous within the limited time, such as soil decontamination, partial demolition, new foundation and building blocks, alteration, repair, new building services installation, acoustic balcony, landscaping, heritage conservation, etc. Without the collaboration among Project Team (PT) members, Wah Ha Estate would not be completed within four years.

Photo: Acoustic balcony (left) and CFD Assessment on Natural Ventilation Studies (right).

The site was subjected to severe traffic noise, industrial noise and railway noise impact. We revisited the design with the Project Civil Engineer, Acoustic Consultant and representatives of Environmental Protection Department to refine the acoustic balcony design. The finalised design not only resolved the noise problem, but also provided sufficient natural ventilation as verified by the Computation Fluid Dynamic (CFD) assessment, which was approved by the Expanded Building Committee of Buildings Department.

The floor area was maximised by adding one storey to one of the wings without overloading the existing structure and foundation. PT coordinated with the Project Building Service Engineer to install light weight Glassfibre Reinforced Polyester water tanks, and use light weight steel frame to support the new machine-room-less lift.

To meet the new standard of Water Supplies Department (WSD), on one occasion, the Building Services team had liaised with the licensed plumbers, Fire Services and Water Pump sub-contractor to have shop drawings revised to illustrate the as-fitted condition in WSD’s office unitl 11:00 p.m. to facilitate WSD’s inspection the following day.

We also developed an optimised self-protective building layout with noise tolerable elements (non-habitable areas such as bathrooms and staircases) located outermost as shielding to inner residential units, and transformed the original corridors into acoustic balconies to screen off noises but at the same time maintain natural ventilation.

Photo: Most of the greenery areas are uncovered and accessible to tenants.

The total greenery requirement of HA projects should not be less than 20% of the site area. By means of a combination of ground-level planters, and green-roof planters on the 5th floor and roof top, Wah Ha Estate has achieved a green coverage of more than 40%.

Photo: Chai Wan Factory Estate before revitalization (left) and Wah Ha Estate (right).

The site is located adjacent to industrial buildings, public transport interchange and Mass Transit Railways station, the PT had been working closely on the mitigation measures to resolve the potential environmental issue since the planning stage. Upon the completion of the revitalisation, by overcoming all industrial-residential interface problems, Wah Ha Estate has turned the historic factory building into sustainable and affordable homes for the community and citizens through adaptive reuse.

Award and Certification
Quality Public Housing Construction and Maintenance Awards 2017 – New Works Projects – Outstanding Building Project Award [Special Mention]
Cross-Strait Architectural Design Awards 2017 – Silver Award (Residential Category)
Structural Excellence Award 2017 – Grand Award (Heritage Category)
Green Building Award 2014 – Merit Award (Existing Buildings Category Building Projects under Planning / Design)
China Green Building Design Label – 3-star
BEAM Plus (New Building Version 1.2) – Provisional Platinum

Hong Kong Housing Authority and Housing Department

Housing Dimensions