Effectiveness of green building rating systems on construction waste management : a Hong Kong study

Abstract

Since the rapid development of Hong Kong, a significant amount of construction and demolition waste has been generated out of numerous construction activities, no matter for buildings and infrastructure projects. The increase in construction and demolition waste throughout the years has put a critical pressure on the capacity of landfills. The Hong Kong government has implemented a series of measures to ameliorate with the issue. The private sector has also strive to tackle the issue by implementing green building standards, Building Environmental Assessment Method Plus (BEAM Plus) and Leadership in Energy and Environmental Design (LEED). It is believed that encouraging the construction industry to actively reduce, reuse, and recycle construction and demolition waste in building projects, is effective in improving construction waste management. Therefore, the effectiveness of green building ratings systems on aiding construction waste management and potential improvements will be scrutinised. Background information including definition and types of construction and demolition waste and the local construction waste management workflow will be briefly reviewed. The existing problems of construction waste management and the relevant government initiatives will be revealed, including posing charges and maintaining a record system for construction and demolition waste disposal. After discussing public policies, the relationship of green building rating systems and construction waste management will also be introduced to demonstrate private sector’s effort. Using a mixed-method approach of quantitative and qualitative analysis along with comparative studies, an increasing trend of disposal rate of construction and demolition waste to landfills is found. The effectiveness of green building rating systems is presented by credit submission and achievement statistics of related credits in BEAM Plus to investigate green building applicants’ willingness in implementing construction and demolition waste recycling, which shows a positive feedback from credit submission and achievement of 15% waste recycling rate by majority of applicants. Surprisingly, a weak causal relationship between the weighting and the effectiveness of these systems on construction waste management is found as similar weighting is given to construction waste management criteria between local and six other green building rating systems adopted in other countries across 5 Asia, Europe and Oceania, where mostly have better construction and demolition waste recycling performance. That said, construction experts have pointed out several problems of green building labels adopted in Hong Kong, including lower participation rate of smaller companies and owners of existing buildings, due to inadequate financial, technical, training resources and supporting hardware for construction waste management, as well as a double dip situation between statutory compliance and the rating systems. Suggestions have been made to the problems raised, which mainly involve improving the local green building rating systems by opting a standalone system assessing construction waste management only. General suggestions to encourage more engagement of developers are provided, aiming to elevate administrative efficiency and linkage with environmental, social, and governance. Additionally, government effort are also vital by lowering statutory threshold for , as well as providing necessary resources and funding to the construction sectors and promoting construction waste recycling industry.