Optimisation of External Wall Insulation Thickness Using Degree-Day Method: A Case Study of Termiz

In this study, the optimal insulation thickness for external walls was analyzed in relation to the climatic conditions of the Termez region. Calculations were carried out using the degree-day (HDD) method, and heat loss, energy consumption and economic factors were evaluated together. The study determined the optimal thicknesses for foam plastic and basalt insulation materials, and observed that insulation thickness increased as the base temperature rose from 18°C to 22°C. The results showed that the optimal thickness for foam plastic is 0.029–0.038 m, and for basalt, 0.021–0.029 m. An increase in HDD values extends the heating period, requiring higher thermal resistance. At the same time, it was found that basalt insulation provides higher efficiency at lower thicknesses. This indicates the importance of material selection. The results of the analysis confirm that the optimal insulation thickness depends directly on climatic conditions, base temperature and material properties. This approach can reduce energy consumption, increase economic efficiency, and ensure thermal comfort in buildings.