## 1 Introduction
The authors coupled a dynamic energy simulation tool with an optimization technique to find the best-combined building roof thermal insulation and solar reflectance and minimize the annual energy consumption. The results showed that a high value of solar reflectance reduced the annual energy consumption for most of the analyzed climate zones. Thus, they concluded that the optimal roof configuration must have high solar reflectance and no/a low insulation level. [PERSON] et al. [15] developed an energy and economic life cycle assessment of cool roofs applied to residential buildings in Southern Spain. The simulations demonstrated that the cool roof decreased the annual energy consumption. The maximum decrease found by the authors was 32%, and it was obtained when a roof with a solar reflectance of 0.1 was retrofitted with a reflective coating with a solar reflectance of 0.9. The LCA analysis reported that savings were 18.33 \(\copyright\)/m\({}^{2}\), and the payback period was around thee years. Some researchers have used validated models to predict the benefits of cool roofs. For instance, [PERSON] et al. [16] studied the thermal behavior of ventilated and non-ventilated roofs during a typical day in Singapore. The authors conducted experiments to validate the concrete roof models. Compared with the roofs with a solar reflectance of 0.1, each 0.1 increase in reflectance reduced the daytime heat gain by 11% on the ventilated roofs and the non-ventilated roofs. The reflective coatings application reduced the daily heat gain by 234 and 135 Wh/m\({}^{2}\) in the ventilated and non-ventilated roofs, respectively. Further, they indicated that compared to non-ventilated roofs (both reflective and non-reflective), the individual use of ventilation and 2.5 cm of expanded polystyrene (EPS) reduced the heat gain by 42 and 68%, respectively. [PERSON] et al. [17] developed a model to study heat transfer in roofs. They used a spectral approximation method to solve the unsteady one-dimensional heat conduction equation. Furthermore, the model was validated using experimental data obtained from measurements made in two identical apartments with concrete roofs located in Singapore. Model predictions showed that on a sunny day, the reflective coating reduced the maximum roof temperature, indoor air temperature, and daytime heat gain by 14.1 \({}^{\circ}\)C, 2.4 \({}^{\circ}\)C, and 0.66 kWh/m\({}^{2}\) (54%), respectively. As shown in the literature review, reflective or cool roofs have brought a series of benefits to the buildings in which they are installed. Thus, it is essential to understand how a cool roof behaves in a particular area. For this purpose, it is necessary to have tools capable of predicting the thermal behavior of a cool roof before its installation to determine if it is feasible from an energy point of view. This work presents the development of a computational tool for modeling the heat transfer of concrete slab-type roofs with traditional and solar reflective coatings. This tool is then used to estimate the temperature reductions and, consequently, the ability of reflective roofs to modulate the heat gains by implementing this technology in buildings situated in four different warm climates in Mexico.