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Recently, there has been a shift toward the embodied energy assessment of buildings. However, the impact of material service life on the life-cycle embodied energy has received little attention. We aimed to address this knowledge gap, particularly in the context of the UAE and investigated the embodied energy associated with the use of concrete and other materials commonly used in residential buildings in the hot desert climate of the UAE.

Using input–output based hybrid analysis, we quantified the life-cycle embodied energy of a villa in the UAE with over 50 years of building life using the average, minimum, and maximum material service life values. Mathematical calculations were performed using MS Excel, and a detailed bill of quantities with >170 building materials and components of the villa were used for investigation.

For the base case, the initial embodied energy was 57% (7390.5 GJ), whereas the recurrent embodied energy was 43% (5,690 GJ) of the life-cycle embodied energy based on average material service life values. The proportion of the recurrent embodied energy with minimum material service life values was increased to 68% of the life-cycle embodied energy, while it dropped to 15% with maximum material service life values.

The findings provide new data to guide building construction in the UAE and show that recurrent embodied energy contributes significantly to life-cycle energy demand. Further, the study of material service life variations provides deeper insights into future building material specifications and management considerations for building maintenance.

The current adverse changes in climatic conditions have necessitated innovative nature-based solutions like blue-green roofs to ensure sustainable built environments. The use of blue-green roofs in combating climate change issues has continued to grow, and its benefits are showcased in many countries' studies. However, there is an absence of reports on the use of this approach in South Africa. Therefore, in ensuring a sustainable built environment through nature-based solutions, this study explored the built environment professional’s knowledge of blue-green roofs, the hindrances to their use and motivations for much wider use of blue-green roofs in the country.

Based on the nature of the study, a quantitative design was adopted and data were obtained from professionals within the built environment through a questionnaire. Data analyses were conducted using the Cronbach alpha test, Kruskal–Wallis H-Test, exploratory factor analysis and fuzzy synthetic evaluation.

The findings revealed a growing knowledge of blue-green roofs, albeit its slow adoption in the country. Also, five critical clusters of hindrances affecting the use of blue-green roofs were identified. These are understanding the blue-green roof concepts, technical, economic, regulation and client hindrances. Furthermore, the ability to manage stormwater properly, provide climate change adaptation and deliver sustainable buildings were the key motivating factors that could drive the use of this innovative solution.

This study offers actionable insights for built environment professionals and stakeholders to address the hindrances to using blue-green roofs in South Africa. Strategies such as improved education, financial incentives and policy development can help overcome some notable hindrances and promote the widespread adoption of blue-green roofs.

The slow adoption of blue-green roofs and the scant nature of research within the built environment required adequate attention to which this current research contributes. Theoretically, being one of the foremost studies in South Africa to explore blue-green roofs, the findings offer a foundation for future studies seeking to explore this roofing system in the country further.