Sustainable Construction In Public Housing Developments

摘要

Disposal of public fill at public filling areas and mixed construction waste at sorting facilities or landfills has been the major approach for construction waste management in Hong Kong. Today, we are running out of both reclamation sites and landfill space. There is an acute need to reduce waste generation and strengthen waste management. The Hong Kong Housing Authority (HA) with a sizable annual public housing production has a major role to play. We actively promote waste reduction, reuse and recycling through a package of innovative measures that straddle through the planning/design stage to construction stage under the '3R' principle. We adopt design tools like BIM, Carbon Emission Estimation Model and Life Cycle Cost/Life Cycle Assessment. We use modular flat design with prefabricated building elements with no-frills finishes and green materials. We also explore adaptive reuse of old buildings where opportunity arises. During construction, we use BIM to optimise construction activities and use large panel formwork, metal green hoarding, timber from sustainable sources, recycled materials like marine mud, ground-granulated blast furnace slag (GGBS) and excavated rock materials. We establish an inventory base and enable transfer of C&D materials between HA contracts. During demolition, we adopt 'selective demolition'. Demolished precast slabs are reused as hard paving slabs. Furniture/equipment was given to NGOs for reuse. A number of enabling systems are also in place to ensure the above measures are embedded into the operational processes for implementation by our contractors, suppliers and contract teams. They include promulgation of green-ready specifications and design guidelines, certification to ISO 14001, effective procurement strategies, selective tendering procedure, listed contractors to be ISO 14001 certified and Performance Assessment Scoring System. We have been staying ahead in the local industry in sustainable construction, and produce 30% less C&D wastes as a result of our efforts. Keywords: Hong Kong Housing Authority; HA; Sustainable construction; ISO 14001.