This half-century-old Chai Wan Factory Estate was once close to being torn down for redevelopment. Following the decision to convert the building into public rental housing in response to the urgent need of increasing short-term housing supply, Arup was brought in by the Hong Kong Housing Authority to deliver a holistic design that would bring this graded historic building up to current statutory requirements and, perhaps more importantly, make it a comfortable living space that accommodates 187 domestic flats for single people and small families.
Adaptive reuse of a historic building
Constructed in 1959, a time when industrial development was prospering in Hong Kong, the Chai Wan Factory Estate is now the only surviving H-shaped factory building, earning its well-deserved Grade II Historic Building status. The main challenge of this conversion project was keeping the shape of the building intact. Through careful planning, about 70% of the existing structure has been retained, not only preserving the original appearance of the building, but also reducing the use of new construction materials, thus minimising construction waste, conserving energy and reducing carbon emissions. A total of HK$3.5 million on materials for concrete cover thickening has been saved.
50⁺ years of history with Grade II Historic Building status
70% of existing structure retained
Affordable yet sustainable home
Our Building Sustainability team conducted microclimate and Computational Fluid Dynamics analyses and tailored a number of green features for this project, including eco-wells to enhance natural ventilation and introduce daylight into domestic flats. Expansion of greenery to over 40% with a landscaped roof help reduce urban heat gain in the Chai Wan neighbourhood. Moreover, two level lighting control in corridors and lift lobbies is used to save energy while water saving in gardening is achieved by rainwater harvesting and drip irrigation system. All these features exemplify that affordable housing could also be a place to pursuit sustainable living.
We plan for better living quality
Such a drastic change of the building’s function involves a careful consideration on residents’ wellbeing and quality of living. For example, the existing ramps are redesigned with gentle stairs and skylight to encourage exercises and healthy lifestyle, as well as induce daylight for better indoor quality. Each residential unit is also carefully oriented to overlook the internal courtyards to optimise ventilation and minimise street noise, particularly noise from the adjacent industrial buildings, public transport interchange and the MTR station.
A showcase well-recognised
Wah Ha Estate is a showcase of adaptive reuse, heritage conservation and sustainable building. With our consultancy services including gap analysis and mapping relevant credits, it has achieved Provisional Platinum rating under BEAM Plus New Buildings V1.2 and 3-star under China Green Building Label, the highest rating under green building schemes in Hong Kong and China respectively. It has also been awarded the Merit Award (Existing Building – Building Projects under Planning/Design) in Green Building Awards 2014, the Winner (Residential - Multiple Houses) in FuturArc Green Leadership Award 2018 and the Grand Award (Hong Kong Building - Renovation/ Revitalisation Category) in Quality Building Award 2018.