The passive cooling strategy has gained significant attention in recent years due to the dreadful impact of active cooling on energy demand and global warming. This work reports on preparing water‐based new roof‐cool paints and studying their utility on thermal and reflectivity performance. The acrylic binder was synthesized via free‐radical water‐based emulsion polymerization using vinyl acrylic monomers ‐three new paint formulations prepared using the as‐prepared acrylic polymer binder with inorganic pigments. To study the roof‐cooling performance of the prepared paints, a cubical plywood‐box model fitted with the painted cement panel was considered the roof with a halogen lamp to simulate the sunlight. The digital thermal sensors are used to record the temperature at the exterior panel surface, interior panel surface, and model box center point to record temperature with time. The study revealed that the prepared roof‐cool paints showed a synergistic effect in reflecting the incident light and heat rejection with peak temperature reduction in the internal air reaching up to 2.8° C inside the model. These type roof‐cool paint coatings on a roof‐top could undoubtedly bring the temperature down inside the building and achieve substantial savings from the energy utilized for cooling comfort.