Abstract
Historic buildings have originally embodied sustainable features. These features responded to the microclimate and site where the building is located. However, with climate change and urban density, active techniques become essential to ensure occupants' indoor comfort. In this regard, the present study attempts to examine and assess the sustainable retrofitting of a historic building in order to maximize energy efficiency without affecting its unique historic character. It also addresses the shortcomings in the literature by considering the cost variation among retrofitting strategies and cost reduction in terms of energy consumption. In this framework, a historic building located on Istanbul University was analyzed in the framework of the case study. The study evaluated the implementation of several retrofit techniques, active and passive, using the energy software DesignBuilder. The implemented retrofit strategies were subsequently evaluated in terms of life cycle cost (LCC), aiming to determine the most cost-optimal and energy-efficient solution. The resultant improvements in energy consumption can serve as a model for forthcoming historic retrofitting projects that take into consideration both economic feasibility and historic buildings' values. (c) 2020 American Society of Civil Engineers.