Sustainable Building Services Design for …

1 Sustainable Building Services Design for affordable Social housing in Hong Kong Ir. LEUNG Senior Building Services Engineer Hong Kong housing Authority HKSAR, China Senior Building Services Engineer, Ir. Stanley TANG, Hong Kong housing Authority, HKSAR, China, Building Services Engineer, Ir. Roger LEUNG, Hong Kong housing Authority, HKSAR, China, Summary The Hong Kong housing Authority (HA) develops and implements a public housing programme which seeks to achieve the Hong Kong Government's policy objective of meeting the housing needs of people who cannot afford private rental housing . Approximately 30% of the Hong Kong population is now living in public rental housing units.

2 The HA plans, builds, manages and maintains different types of public housing , including rental housing estates, interim housing estates, and transit centres. In addition, the HA owns and operates some flatted factories and ancillary commercial and other non-domestic facilities. In the context of public housing development, the missions of the HA are to provide affordable quality housing and other housing related Services to meet the needs of the customers in a proactive and caring manner; and to ensure cost-effective and rational use of public resources in service delivery and allocation of housing assistance in an open and equitable manner. This paper will focus on some of the measures that realize quality living in affordable social housing through Sustainable Building Services designs to achieve enhanced cost-effectiveness, usability, reliability, maintainability, environmental friendliness and social responsibilities.

3 Keywords: Sustainable , housing , Building Services , Design , renewable, energy, carbon emission 1. Public housing in Hong Kong In 1953, a serious fire in Shek Kip Mei squatter area marked the beginning of the government s involvement in the construction of multi-storey resettlement buildings. To cope with the increasing needs of housing in the territory at that time, the then Public Works Department built Government Low-Cost housing in the 1960s for low income families. To address the accommodation need of a sharply increasing population, the Government announced the Ten-year housing Programme in 1972. The Hong Kong housing Authority (HA) was established in 1973 to oversee public housing issues of Hong Kong.

4 Currently about 30% of the total Hong Kong population lives in public rental housing units. The housing Department (HD) is the executive arm of the HA to discharge her statutory responsibilities which include, inter alia, the provisions, operation and maintenance of Building Services installations for public housing . 2. The Missions of the Hong Kong housing Authority The mission of the HA is to provide affordable quality housing and other housing related Services to meet the needs of the customers in a proactive and caring manner. It is also to ensure cost-effective and rational use of public resources in service delivery and allocation of housing assistance in an open and equitable manner.

5 The four core values of the Authority, viz. Caring, Customer-focused, Creative, Committed (the 4 C s) are manifested in the continuous pursuit of improvement of the Design and provision of Building Services installations at public housing estates to achieve enhanced cost-effectiveness, usability, reliability, maintainability, environmental friendliness and social responsibilities. We provide affordable quality housing incorporating Sustainable considerations to balance the economic, social and environmental needs and concerns of our stakeholders in housing development and management programmes in pursuit of performance excellence and harmonious living environment.

6 3. Building Services Installations - an Indispensable Element for Quality housing While the mission of the HA is to provide quality housing , quality Building Services installations are integrated and indispensable to meet this mission. In a densely populated metropolis like Hong Kong, public housing buildings are, without exception, reaching out for the sky to compete for as much space as possible. Today, a typical public housing Building would be a 41-storey high-rise Building accommodating several hundred residential units. In the context of quality Building Services designs for high rise domestic buildings, all factors including safety, usability, reliability, maintainability, cost-effectiveness, environmental friendliness, rational use of public resources and social responsibilities have to be carefully considered and balanced before coming up with a Design .

7 4. Design for Sustainability Energy conservation in Hong Kong has received increasing attention over the years. This is a crucial element in Sustainable development and helps combat global warming. As a general Design principle, all the Building Services installations are designed to achieve a high level of energy efficiency. Moreover, we have made it mandatory that all new Building Services designs shall fully comply with the requirements of Hong Kong s Building Energy Codes since their first promulgation more than a decade ago. The compliance of the Codes is only made mandatory in 2011. Today, we have received over 300 energy certificates covering various Building Services systems including lift and escalator, air-conditioning, electrical and lighting installations.

8 Over the years we have been exploring into various technological fronts of system designs and equipment efficiency in a bid to improve customer satisfaction as well as further reducing our buildings carbon footprints. In this paper, we will find detailed delineations of our recent efforts in achieving our Sustainable Design objectives through the exploration and adoption of green engineering initiatives. These include green lighting Design ; energy efficient Building Services equipment, renewable energy, hygienic refuse handling, hybrid ventilation, improved water supplies, water conservation, uninterrupted lift service, carbon emission estimation and energy audits.

9 Green Lighting Design As lighting energy forms a substantial part of the total energy consumption of a Building , energy efficient fluorescent lamps have been used extensively in our Building projects. We have been working closely with lighting suppliers and conducting trials to source luminaries and lamps of higher efficacy that can suit our applications. The Design principle is to deliver the required levels of lighting performance in terms of illuminance, uniformity, colour rendering and glare, yet cost-effective and easy to maintain, while complying with the relevant statutory requirements. In 2008, the new edition of Design Manual for Barrier Free Access was released which has presented great challenges to Building Services engineers.

10 The manual specifies a minimum illumination level of 85 lux along communal passageways in buildings to take care of persons with special needs. When compared with our original Design illumination level of 50 lux, the adoption of the new requirements would lead to almost doubling the communal lighting energy consumption and hence associated CO2 emission. To reduce the environmental impact of the new Design requirement, a new lighting control system allowing two levels of illumination was developed in 2009. The new Design comprises two sets of lightings provided along the communal passageways (Fig. 1). One set is constantly powered to provide a minimum illuminance of 30 lux at floor level for typical corridor and staircase and 50 lux for typical lift lobby.