@article{article_781562, title={A LIFE CYCLE COSTING APPROACH TO DETERMINE THE OPTIMUM INSULATION THICKNESS OF EXISTING BUILDINGS}, journal={Isı Bilimi ve Tekniği Dergisi}, volume={40}, pages={1–14}, year={2020}, author={Çağlayan, Semih and Özorhon, Beliz and Özcan, Gülbin and Yiğit, Sadık}, keywords={Optimum yalıtım kalınlığı, ısı yalıtımı gereksinimleri, mevcut binaların enerji verimliliği, yaşam dönemi maliyetlemesi}, abstract={The ongoing global increase of energy prices and energy use has directed many researchers to study energy conservation strategies as an instrument of sustainable development. A common yet effective strategy is to insulate the exterior envelope of existing buildings in an attempt to improve energy efficiency. While an insulation application requires an initial investment, it helps the building to spend less energy during its operation. In order to sustain feasibility, it is crucial to find an insulation thickness that is cost-effective and especially applicable in developing countries. The objective of this study is to determine the optimum insulation thickness for existing buildings by using a representative building approach. For this purpose, insulation alternatives including 15 cm stone wool on ceilings and expanded polystyrene (EPS) on exterior walls at varying thicknesses were applied on a representative existing building. A variety of EPS thicknesses (from 1 cm to 20 cm) were analyzed as alternatives for the insulation application. Annual energy requirement of the building was calculated by the heat balance method by conducting a dynamic analysis. Life cycle costing (LCC) analysis was performed to find out which alternative results in the best economical outcome. The optimum insulation thicknesses were obtained for various climate regions by considering a number of scenarios with different discount and inflation rates. The results demonstrated the inadequacy of the national regulation’s current insulation limits, as it was observed that the optimum insulation thicknesses were significantly greater than the limiting values in the national standard. To overcome this inadequacy, it is suggested to effectively improve energy efficiency by lowering the limiting heat transfer coefficients in the standard.}, number={1}, publisher={Türk Isı Bilimi ve Tekniği Derneği}