Passive cooling design strategies for retrofit of residential tower blocks in Northern Cyprus

This research investigates potential passive design strategies for improving the thermal performance of existing residential tower block (RTB) in Famagusta, Northern Cyprus. In a Mediterranean island that experiences hot and humid temperatures throughout the year, residential buildings need to be adaptable to the climate in order to improve the thermal comfort of occupants. The current housing stock includes a prevalence of high density, medium and low-rise residential tower block developments without implementing any insulation materials. The objective of this study is to develop and test passive cooling design strategies into retrofitting ill-performing residential tower blocks in the coastal city of Famagusta. As an initial step, the performance of a case study was modelled and simulated via employing Integrated Environmental Solutions Virtual Environment (IES-VE) software add-ins Apache-Sim Dynamic Thermal Simulation. The results from the base case model were analyzed according to the adaptive comfort of CIBSE Technical Memorandum 52 guidelines: The Limits of Thermal Comfort - Avoiding Overheating in European Buildings. The spaces studied (living room and bedrooms) within the case study sample flats were observed to exceed the acceptable limits of thermal comfort; particularly living rooms with this zone exceeding the upper limit for overheating by up to 9 hours daily. The main reasons for the problematic thermal performance were identified as resulting from: infiltration through the building fabric, the lack of sufficient ventilation through the living spaces and excessive heat gains through the large areas of glazing. The internal operating temperatures of the simulated flats remain high throughout the day and night in a typical summer day, ranging from a maximum of 36.5 ̊ C to a minimum of 28.5 ̊ CThe study also analyses the effectiveness of two basic passive cooling strategies (shading and night ventilation) of 3 sample flats sharing the same orientation, and floor plan but located at different levels within the RTBs. Furthermore, the implications in the seasonal cooling and assessment when considering the adoption of climate-related set-point temperatures (i.e. adaptive comfort approach), beyond the assumed common standard, are also evaluated