A comprehensive cost-optimal approach for energy retrofit of existing multi-family buildings: Application to apartment blocks in Turkey

This research presents a comprehensive cost-optimal approach for existing building retrofits. Theapproach incorporates energy efficiency measures related to building envelope, building energy systemsand renewable energy, all at once. Moreover, the cost-optimal calculation scope is extended throughintegration of occupant behaviour.The comprehensive approach is implemented for a reference building which represents high-rise apart-ment blocks in Turkey; these building types accommodate 4500 families corresponding to 23.1% ofthe national households. Three different climatic regions, that show significant distinction from eachother, were selected for the sample application of the approach in order to refer different climates. Cost-optimal calculations were performed for more than 1300 scenarios. Integration of occupant behaviourinto this calculation procedure was demonstrated with sensitivity analyses; the present application ofthe approach was focused on the use of window openings by occupants.Results reveal that cost-effective energy saving potential is higher than 70% in high-rise apartments.Moreover, occupant behaviour related to window openings is able to raise this rate above 80%. Thefindings indicate the necessity of comprehensive approach and demonstrate that integration of occupantbehaviour into cost-optimal calculations is fundamental in order to reach significant and stable results