Paper Title
A Study On Determination Of Optimum Thermal Insulation Thickness Using Life Cycle Cost Analysis

In this paper, a systematic approach for optimization of thermal insulation thickness used in external walls was developed. The optimization model was based on the life cycle cost analysis using present worth method. The heat losses and the heating energy requirement of a prototype building were calculated by using degree-days utilizing long-term meteorological temperature data. The total cost, including heating cost, insulation material cost and installation of insulation cost, was calculated, and the cost curves were obtained for different fuel types to determine the optimum insulation thicknesses. The results show that the optimum thermal insulation thickness varied between 4.2 and 10.3 cm depending on fuel types. Moreover, the optimum insulation thickness varied more dramatically between 1.6 and 18.5 cm with different degree-days. Keywords - Life Cycle Cost; Optimum Thermal Insulation Thickness; Energy Savings.