As temperatures continue to rise across Tamil Nadu and heatwaves become more frequent, reducing heat exposure in buildings has become a key climate adaptation priority. Recognising heatwaves as a state-specific disaster, the Government of Tamil Nadu is advancing a range of heat mitigation measures to improve thermal comfort, protect vulnerable communities, and strengthen climate resilience.
One of the most effective and scalable passive cooling interventions is the implementation of cool roofs. By reflecting solar radiation and reducing heat absorption, cool roofs help lower roof surface temperatures, improve indoor thermal comfort, and reduce dependence on mechanical cooling systems.
To support large-scale adoption, the Tamil Nadu Green Climate Company (TNGCC), under the Tamil Nadu Climate Change Mission (TNCCM), in partnership with the United Nations Environment Programme (UNEP), has developed the Standard Operating Procedure (SOP) for Cool Roof Coating Application under the BeCool Project, supported by the Swiss Agency for Development and Cooperation (SDC). The SOP provides a standardized framework for planning, procurement, implementation, quality assurance, and maintenance of cool roof coating systems across Tamil Nadu.
From Evidence to Action
The SOP draws upon lessons from pilot projects implemented in affordable housing and government schools across the state. At the Lighthouse Resettlement Project in Perumbakkam, cool roof coatings reduced rooftop surface temperatures by 4.5–8°C and ceiling temperatures by 1.5–3°C. Similarly, pilot interventions under the Tamil Nadu Green Schools Programme reduced ceiling temperatures by 4–5°C and classroom temperatures by up to 3°C, demonstrating the effectiveness of cool roofs in improving thermal comfort and reducing heat stress.
Building on these successful demonstrations, Tamil Nadu is scaling cool roof interventions across schools, public buildings, and affordable housing developments as part of a broader strategy to create climate-resilient built environments.
A Practical Guide for Implementation
The SOP serves as a common reference for government departments, engineers, contractors, and implementing agencies. It standardizes every stage of implementation—from roof inspection and feasibility assessment to material selection, surface preparation, coating application, quality assurance, safety measures, and long-term maintenance.
The document also emphasizes that cool roofs should be implemented alongside complementary passive cooling measures such as shading, natural ventilation, insulation, and nature-based solutions to maximize thermal comfort and energy savings.
Advancing Climate Resilience
The publication of this SOP marks an important step in mainstreaming sustainable cooling solutions across Tamil Nadu. By translating field experience and technical knowledge into a practical implementation framework, the SOP enables stakeholders to deploy cool roof interventions at scale while maintaining high standards of quality and performance.
As communities continue to face growing heat risks, the SOP provides a pathway to improve public health, enhance thermal comfort, reduce energy demand, and support Tamil Nadu’s broader climate resilience and adaptation goals.
