Optimum Insulation Thickness for the Exterior Walls of Buildings in Turkey Based on Different Materials, Energy Sources and Climate Regions

摘要

Thermal insulationimproves the strength and longevity of buildings by reducing energyconsumption, and as a related result, improved energy use. The selection ofinsulation material is governed by important parameters, including the averageoutdoor air temperature, the thermal conductivity of the buildings and the costof the insulation material. Increases in the thickness of the insulationmaterial will gradually decrease the energy consumption for heating; however,the insulation thickness has an optimum value that minimises the totalinvestment cost, and determination of this optimum value is critical foreconomic analysis. In this paper, a life-cycle cost analysis is presented toshow the optimum insulation thickness, energy savings over a lifetime of 15years and payback periods for six different fuels and insulation materials forfour cities in Turkey selected from climate regions identified by the TurkishThermal Insulation Standard (TS 825). Mu?la (1st region), Kocaeli (2nd region),Ankara (3rd region) and Ardahan (4th region) were selected for analysis of asandwich-type wall constructed from the following six insulation materials:extruded polystyrene, expanded polystyrene, glass wool, rock wool,polyisocyanurate and polyurethane. The calculations were also made on the basisof six different fuels, such as motorin, natural gas, propane (LPG),electricity, coal (imported), and fuel-oil No. 4. As a consequence, resultsdemonstated that the optimum insulation thickness vary between 2.8 cm and 45.1cm, with energy savings between 16.4 ?/m~(2) and 479 ?/m~(2), and payback periodsfluctuating between 0.078 and 0.860 years, depending on the city, the insulationmaterial, and the cost of fuel.