Application of green adaptive reuse (GAR) is considered to be difficult and lacks the attention in the field of research. The potential of implementing GAR has become uncertain since the way of implementing specific practices is still unknown when the context is different. In Sri Lanka, building professionals are reluctant to use GAR approach due to various obstacles. Specially, due to the scarcity of land, high energy consumption and costs, most of the existing abandoned buildings in Sri Lanka are demolished despite the significant benefits of GAR of buildings. Thus, this research is aimed to develop a framework that could facilitate the implemention of GAR for existing buildings in Sri Lanka. A qualitative research approach was followed for this research with semi-structured interviews. The findings were analyzed using the content analysis method. Significant factors for the implementation of GAR approach were identified mainly under seven criteria including physical, economical, functional, technological, social, legal and political. Further, barriers and strategies for the implementation of GAR for existing buildings in Sri Lanka were revealed. Based on the findings, a framework was developed as a guidance for the implementation of GAR for existing buildings in Sri Lanka which was the key outcome of this study.

The aim of this research is to develop a framework for the implementation of Green BIM technology for existing buildings in Sri Lankan context. A multiple case study was conducted under a qualitative research approach. Two existing buildings were selected for the cases. Autodesk Revit was used to design the BIM models of the cases. As Green BIM techniques solar analysis and energy analysis were conducted using Green Building Studio simulation software. Solar simulation results included cumulative insolation as 463,825 and 480,538 kwh, PV energy production as 231,659 and 111,024 kwh/year, energy savings as $34,749 and $16,654 and pay pack periods as 18.5 and 15 years for case 01 and 02, respectively. Further, research revealed the challenges during the application of Green BIM for existing buildings when building data are not adequately available. Moreover, this study proposed the solutions that are taken during the study to overcome the challenges. This study justifies the potential of Green BIM implementation for existing buildings through an in-depth analysis of challenges and possible solutions with a framework that can be used. This encourages building owners and facility managers towards using Green BIM for existing buildings.

The steady growth of the Sri Lankan apparel manufacturing sector over the last three decades has resulted in generating large amount of solid apparel waste. Currently, it is a massive environmental and financial burden of the sector. As a solution, few apparel manufacturers have initiated using apparel waste, specifically the cotton apparel waste for biomass boilers. The apparel sector as one of the major thermal energy consumers, they consider it as a possible solution not only for the apparel waste disposal issue, but also for the challenge of getting continuous supply of firewood for the boilers. However, the promotion of such a solution throughout the apparel industry is impractical without a feasibility study in terms of social, environmental, financial, legal and technical aspects over its mechanism. Therefore, this research focused to identify the feasibility of using cotton apparel waste for biomass boilers as an energy source. Towards this aim, a qualitative research approach was followed involving the case study strategy. Basically, two cases were selected and analysed the feasibility of using cotton waste for boilers under pre-determined feasibility criteria in detail. Data collection for the case study was done through a document survey and expert interviews. Findings revealed the entire feasibility of environmental, financial, legal and technical aspects and in overall it can be concluded that the use of cotton apparel waste for biomass boilers as an energy source is feasible. Accordingly, this study provides insights into making decisions on managing both waste disposal and heat energy requirement issues of the apparel factories.