Methodology to define cost-optimal level of architectural measures for energy efficient retrofits of existing detached residential buildings in Turkey

Building stock is playing a crucial role in the energy policy of every society. Number and area of residential buildings in every country provide a priority for this typology of building in large scale decision making. Uncertainties in users' behaviours make it difficult to have a proper assumption in residential buildings. In Turkey, buildings are responsible for a large amount of energy consumption and have tremendous energy saving potential. It is necessary to have more accurate results and consider different aspects of any retrofit action before application. To increase yearly retrofit rate, owners should involve in the actions as financiers otherwise relying solely on the amount of governmental contributions will lead to low retrofit rate thus disadvantages of enormous energy consumption will not be demolition. This study is trying to introduce a new methodology to define proper retrofit measures that are enthusiastic for building owners and make them encourage to involve in the action as financiers. In this way, three case study buildings with same geometry but different envelope properties in three of five main climates of Turkey defined to analyse. An adopted methodology focuses on the amount of money that should be paid by owners in any retrofit scenarios. When the amount is more than the payable amount, the possibility of staged action is discussed. The results are revealing that optimum measures should be applied in at least two stages to be acceptable from owners' satisfaction point of view. Except cold climate, the actions that are providing most energy savings are not desirable when considering the payback period and global cost issues.