Ali Sedki Yassin
IMPROVING INDOOR THERMAL COMFORT IN RESIDENTIAL BUILDINGS IN HOT-ARID CLIMATES THROUGH THE COMBINATION OF NATURAL VENTILATION AND INSULATION RETROFITTING TECHNIQUES - Case study: Existing social housing stocks in Greater Cairo
Abstract
Achieving thermal comfort in buildings has currently become an urgent need, because of excessive demand in energy consumption across the length and breadth of the world. Accordingly, academics, policy-makers, regulators and governments are striving to find solutions that can be applied to achieve thermal comfort in buildings without excessive consumption of energy. Corollary to this, thermal comfort and energy efficiency in buildings are two faces on the same coin. Egypt is characterised by haphazard utilisation of prototypical design in public housing projects. The haphazard utilisation of prototypical strategy is in stark contrast with the conventional strategy, which takes into account the various climatic design issues in carrying out social housing projects. Previous studies indicated that the thermal behaviour of same building stock varies across Egypt due to different climatic regions. This evidence overtly illuminates that in order to ensure thermal comfort in residential buildings in Egypt, a combined strategy that takes into consideration the prevailing climatic condition is imperative. It is therefore, against this backdrop that this study examined how the combination of natural ventilation behavioural strategies and insulation retrofitting technique influences indoor thermal comfort without using any mechanical cooling or heating systems. In order to accomplish the research aim, the problem of thermal comfort in the prototype design social housing building stocks within the hot arid climate of Egypt was identified. Further, the Integrated Environmental Solution – Virtual Environment (IESVE) was adopted to predict the building thermal behaviour whilst applying natural ventilation behavioural strategies on the one hand and its combination with insulation retrofitting technique on the other hand. Predictions were comparatively analyzed to identify the optimum strategy during each month of the year. Cross analyses were carried out to ascertain either this strategy highlights the differences among building orientations or otherwise. In addition, a comparison between typical and upper floor was conducted to highlight their differences. By applying natural ventilation behavioural strategies, scenarios of natural ventilation were categorized into three; the base case scenario, the actual behavioral scenarios and the hypothetical suggested scenarios. The results illuminated that, In terms of the summer season, the hypothetical suggested scenario of cross night purge ventilation revealed a considerable improvement in indoor thermal comfort. Moreover, whilst natural ventilation scenarios had a modest improvement in thermal comfort in springautumn period, it had a negative effect in winter season. In regards to the combination strategy, simulation results revealed that whilst this strategy played a major role in increasing indoor thermal comfort and reducing cooling demand in summer period, it had very slight impact on enhancing indoor comfort and reducing heating demand (in winter) and heating or cooling demand (in spring-autumn periods). However, by comparing the combined strategy with natural ventilation only, it was deduced that the insulation technique had relatively small impact on thermal comfort enhancement in all periods of the year. Improving indoor thermal comfort in residential buildings in hot‐arid climates through the combination of natural ventilation and insulation retrofitting techniques II The study further assessed the effect of orientation on indoor thermal comfort via the utilisation of natural ventilation only as well as the combined strategy in winter, summer and spring-autumn periods. The observable fact illuminated that the orientation has no significant effect on indoor thermal comfort in winter, summer and spring-autumn seasons. Finally, the comparison between typical and upper floor confirmed that the difference between them is negligible in terms of thermal comfort.
XXVI Cycle
Tecnologia dell'Architettura
Home Institution: Università degli Studi di Ferrara
ICAR 12
Tutor: Theo Zaffagnini
