Possibilidades para o emprego do sistema de fachada ventilada opaca em edifícios comerciais nas oito zonas bioclimáticas do Brasil.

Abstract

On a scenario of economical stability Brazil has seen, since the millennium turn over, significant growth on the construction sector. It has been driven by the large supply of public credit, allowing the renovation of property inventories on the country. With a new political and economic perspective on the horizon, the concern on the buildings performance and the aim for a greater energy efficiency will allow a competitive differential for stakeholders, at a market that returns the competition for clients and resources. The idea of regulate and standardize materials, rationalizing process, in parallel with legal adjustment and new propositions for the area are welcome, and it is believed that will be better deepened and consolidated on the next years. This study presents the results of a comparative study, focused on the thermic and energetic performance, regarding the insertion on commercial buildings of a technology that is innovative at a local level: the double skin wall, also knows as opaque ventilated façade. This system provides a faster work execution and a lowest waste production, if compared with the sealing systems normally used by the construction industry. Within this scenario, the importance of this study is justified by the expectancy of the viability on the insertion of new technologies yet unexplored in our context. This study main objective is to present in what extend the double skin wall can contribute for the reduction of energy consumption through a smaller dependency of artificial conditioning and the enlargement of the users comfort in the country commercial buildings in the country. Considering a combination of a high occupation density and intense use internal energy, the thermal and energetic performance are evaluated, made since an exploratory model, to be adopted in all eight Brazilian climatic zones. The base building with the proposed system is evaluated and compared to another analogous with traditional envelope of concrete two cores blocks and layer mortar coating. Both the thermal and the energetic performance of the models have been studied, as well as the implementation costs, based on the energy savings potential on periods of ten, thirty and fifty years. The results show that, only with the use of natural ventilation, the proposed system has a higher comfort in three of the eight Brazilian Climatic Zones. Through the expected of energy consumption by calculated accounting for the need of air conditioning, the proposed system provides and better performance in four of Brazilian Bioclimatic Zones. The economic evaluation performed for these four areas with higher performance indicated that the installation of the proposed system is not possible only the value of the energy saved, although it may reflect the optimization of HVAC system installed.