19 Septembre – Thesis defense - Ferran Yusta Garcia
10 h Amphi 3 - Ecole Nationale Supérieure d'Architecture et de Paysage de Bordeaux (Talence)
Climatic seasons method : proposition of a bioclimatic architectural approach for low energy consumption buildings in very hot climates.
The last 25 years have been ground-breaking in architectural design on low energy consumption in cold climate, mainly in north-western cultures. For an architect today, the method to design a passive house in cold weather and the choice of the Architectural Actions (AA), are clearly established. When the question comes to how to build a passive house in warmer, hot, and very hot climates, the strategies are poor and often results of a combination of western strategies with a local relook. From several visits in Middle East countries, Saudi Arabia, UAE, Oman, Palestine, Qatar, we concluded that the strategy for low consumption houses is not established yet and poorly grasped. The lack of training on low energy consumption in hot climate and the low price of energy, force designers and owners to relay on over usage of air-conditioning systems as measures to catch up on poor bioclimatic design.
This PhD proposes a new approach on bioclimatic design for hot climates from an architect point of view. It is based on a Cooling Degrees Days (CDD) and Heating Degrees Days (HDD) approach, a state of art of contemporary architecture and professional experience. Local climates are classified according to the six situation of the exterior temperature during night/day : cold/cold, cold/cool, cool/warm, cold/hot, cool/hot, and hot/hot as CDD and HDD of the twelve month of the year, January to December, are or not significant. A group of days on one of those situation will be called “climatic season”. In parallel we consider two main situations: people keep the house closed to the exterior or opened to the exterior, and will associate passive strategies to these two different ways to live in the house: “cold” and “hot” to a closed house and “cool” and “warm” to a house opened up to the exterior. This method allows classifying any climate in the world under these six climatic seasons. Our climate classification is associated to different strategies that we will call “architectural actions” as house is closed or opened. We could already start to design a house from here, but to better understand the influence of each action we have created a E+ thermic model to analyse individually the effect of a single architectural action. The performance of each action is evaluated under the situations of six representative journeys of the cold/cold, cold/cool, cool/warm, cold/hot, cool/hot, and hot/hot situations as well as a year round on a very hot city: Dubai. The result of the effect good or bad of action during each different season situation allows us to create the best combination of architectural actions that are best for a year round climate resulting of the combination of several climatic seasons. This low-tech method help us to find the common features of the houses of different hot climates of a big region and find the best typology. We have carried in parallel a cost study of the base house and the financial incidence of each single action to evaluate also the payback period by action. Three case studies done during the period of this study are analysed as examples of decision taking method for architects and engineers: Solar Decathlon Middle East house prototype named BaityKool (www.BaityKool.com) built for Dubaï, a family house in Makkah in Arabia Saoudia and the improvement of collective building in Nablus in Palestine.