Testing the nexus between C&D waste management strategies & GHG emission performances : the case of UK student accommodation refurbishment projects

All governments, industry sectors and societies each have a pivotal role to play if we are to mitigate anthropogenic climate change. For the construction industry, limiting emissions and addressing issues of sustainability is not just important for reducing the environmental impacts of the sector, but is simply good practice. This research investigates the nexus between the generation and management of waste and greenhouse gas performance in the refurbishment sector, with specific focus on UK student accommodation projects. Performance data from three case study projects were analysed in order to: evaluate the types and extent of wastes and how they are managed; the greenhouse gas impacts of each project waste management strategy; and an assessment is undertaken to estimate the number of BREEAM waste credits that each project would have achieved. The research concludes that the overall greenhouse gas performance of a project’s waste management strategy is highly dependent on how specific high emission impact factor waste streams are managed, and notably, there is a disconnect between waste targets, legislation and sustainability benchmarking schemes that measure success based on the levels of diverting waste from landfill, and the emission performance of waste management strategies. A key area of risk potentially overlooked relates to the scenarios where proportionally small quantities of high emission wastes (e.g. plastics) were sent to landfill alongside large quantities of low emission wastes (e.g. aggregates, bricks, etc.). To ensure the increased emission performance of the refurbishment sector, greater focus is needed on preventing specific categories of waste from the landfill pathway

Support for the integration of green roof constructions within Chinese building energy performance policies

Green roofs could act as a thermal buffer in buildings and offer potential energy savings. However, the energy benefits from green roofs are not usually properly recognised by traditional building energy regulations. Building energy regulations are traditionally over-simplistic during the assessment of the energy performance of complex building constructions. In the case of green roof designs, it is essential that the assessment mechanisms should not ignore the complex heat and moisture balances within the green roof layers. In this paper, dynamic energy modelling that considers the complexity within the green roof layers is adopted to guide policy makers in China on the relationship between using specific thicknesses of roof insulation against green roof layers. Simulations are run for a residential building type by also considering different thermal envelope characteristics across eight large Chinese cities and within the five main climatic zones of China. Results that link the green roof characteristics with respective traditional insulation layers are produced for all cities and it is found that optimising the plant and soil characteristics of green roofs in some climates could substitute more than 125 mm of roof insulation, while less optimum green roof types could only replace about 25 mm of roof insulation

Environmental assessment schemes for non-domestic building refurbishment in the Malaysian context

The increase in global warming, energy consumption and greenhouse gas emissions has gained attention in various regions. In Malaysia, the government announced a voluntary commitment to reduce 40% of CO 2 emissions by 2020 and to refurbish 100 government buildings. Existing buildings make a large contribution to energy consumption and CO 2 emissions, therefore refurbishing existing buildings is an essential strategy to achieve the commitment. There is no single assessment scheme for building refurbishment in Malaysia and hence, this study aims to develop a comprehensive list of assessment themes and sub-themes for building refurbishment purposes. It examines and compares 10 assessment schemes from various countries: BREEAM, LEED, CASBEE, BEAM Plus, GBLS, Green Star, HQE, Green Mark, GBI and MyCrest. The findings revealed fourteen themes that were considered for assessment: management, sustainable site, transport, indoor environmental quality (IEQ), water, waste, material, energy, pollution, innovation, economic, social, culture and quality of services. Energy and IEQ are dominant themes in all assessment schemes. Most of the schemes are considered relatively weak in evaluating economic and social aspects, in comparison to environmental aspects. The assessment of quality of services is overlooked in most of the schemes, including GBI and MyCrest in Malaysia. Outcomes from this paper will form the baseline for a new environmental assessment scheme that aimed at non-domestic building refurbishments in Malaysia. A new model is proposed for the development of an environmental assessment scheme in the further stage

Systematising multidisciplinary sustainable building design processes utilising BIM

Purpose – Sustainability considerations are often treated as an add-on to building design, following ad-hoc processes for their implementation. The purpose of this study was to investigate, model, and facilitate the early stages of Building Information Modelling (BIM) enabled Sustainable Building Design (SBD) by formalising the ad-hoc working relationships of the best practices in order to standardise the optimal collaboration workflows. Design/methodology/approach – Four stages of data collection were conducted, including a total of 32 semistructured interviews with industry experts from 17 organisations. Fourteen “best practice” case studies were identified, and roles and responsibilities, resources, information exchanges, interdependencies, timing and sequence of events, and critical decisions were examined. Findings – The research classified the critical components of SBD into a framework utilising content and thematic analyses. These components were coordinated explicitly into a systematic process, which followed Concurrent Engineering (CE) principles utilising Integrated DEFinition (IDEF) 3 structured diagramming technique. Then, Green BIM Box (GBB) workflow management prototype tool was developed to analyse communication and delivery of BIM-enabled SBD in a centralised system. Originality/value – This study represents an improvement to previous attempts to systematically define the BIM-enabled SBD process for the early stages. The results support the idea that a transparent SBD process, which follows specified communication patterns, can assist in achieving sustainability efficiently in terms of time, cost, and effort