Affordable green materials for developed cool roof applications: A review

Developing countries encounter challenges in adopting advanced roof systems due to the complexities associated with implementing advanced materials and techniques. This study introduces an advanced four-stage approach as a combined technique, aiming to formulate an innovative affordable cool roof application that addresses the limitations of contemporary cool roof systems. The first stage involves reviewing Cool Roof Materials (CRMs) by classifying them into three categories: traditional, modern, and advanced roofing systems, with subclasses for each category. In the second stage, Affordable Green Materials (AGMs) are reviewed to suggest alternatives aligned with the study objectives. The third stage focuses on monitoring performance methods to evaluate applicability, while the fourth stage assesses the potential transformation of these alternatives into future fabrication processes. The study suggested a natural composite sandwich panel that incorporates three main layers, with multiple potential materials alternatives for each layer. The main panel consists of a reflective coating layer, a natural insulation composite layer, and a substrate layer. It could result in a significant 44 % decrease in surface temperature, with potential energy savings reaching up to 70 % and reductions in cooling loads of up to 51 %. It forms the basis of a new affordable cooling roof technology that effectively addresses the complexity of contemporary systems, potentially resulting in significant advances in passive cooling systems. The review also identifies areas requiring further research. Ultimately, this combination of environmentally friendly solutions could pave the way for holistic innovation in sustainable building design, contributing substantially to global climate objectives and energy-saving targets.