Assessment of design and construction related factors influencing maintainability of green roofs: a case of high-rise buildings in Sri Lanka

Poor design and construction practices can significantly impact the future maintainability of green roofs in high-rise buildings. While previous studies have focused on green roof construction and design features, this research specifically evaluates the effects of design and construction related factors on maintainability of green roofs, with a focus on high-rise buildings in Sri Lanka. The study begins by reviewing literature on green roofs, their maintainability, and the design and construction factors that influence maintainability. The identified factors were used as a basis for evaluating the effects of design and construction on future maintainability of green roofs. A deductive approach is adopted within a quantitative research design, utilising a survey strategy. A questionnaire survey was conducted among 58 experienced construction professionals, while four expert interviews are conducted to gather additional insights. Data analysis techniques include the Relative Importance Index and content analysis. As derived through analysis, initial cost and roof design were identified as design-related key factors, while cost of construction and availability of machinery and materials were the construction related key factors influencing maintainability of green roofs. Accordingly, the study proposed strategies to enhance the maintainability of green roofs in Sri Lankan high-rise buildings focusing on cost effectiveness, design effectiveness and effective management of green roofs. As a main implication, this research contributes to the development of sustainable and maintainable green roofs in Sri Lanka by providing valuable insights for the construction professionals and policy makers in the country.