Determination and Modeling of Optimum Insulation Thickness for Thermal Insulation of Buildings in All City Centers of Turkey

In this study, research has been carried out in which the optimum insulation thickness for the thermal insulation of buildings in all city centers of Turkey is determined according to life cycle cost analysis. Besides, the total annual net savings of the buildings in all city centers and the payback period of the insulation were concluded according to the determined optimum insulation thickness. In the calculations, it is assumed that natural gas is used for heating the buildings, and electrical energy is used for cooling. Besides, four different insulation materials (XPS, EPS, PUR, and Rock wool) were selected as the most preferred thermal insulation material in Turkey. The methods applied to determine the buildings' optimum insulation thickness are very time-consuming and dependent on many parameters. Twelve different models have been developed for all city centers that determine the optimum insulation thickness depending on the number of Degree-Days of buildings that need only heating, cooling only, heating and cooling to create a practical approach in determining the optimum insulation thickness. The regression analysis models' suitability using MATLAB R2019a program, with R-2 values being the main criterion, SEE (Standard error estimate), and RMSE (Root mean square error) values are considered. Accordingly, when the similarity between the developed models and optimal insulation thicknesses obtained from theoretical calculations was examined, it was determined that R-2 values were between 0.9683 and 0.9997. It is predicted that this study will provide a practical solution for researchers and designers working on this subject.