Desempenho de edificação residencial no Sul do Brasil sob a ótica energética e econômica: da NBR 15575 à Passive House

Abstract

The need to reduce costs and to accelerate the construction process in social housing is based on rationalized and low quality building systems, generating inefficient buildings in many aspects, including thermal and energy performance. From 2013, with the publication of NBR 15575 (Brazilian Standard of Housing Buildings - Performance), it became mandatory to meet a series of criteria and requirements, to improve the quality of buildings in the country. However, this standard is not very demanding, and does not guarantee the proper performance of the buildings. In this context, the objective of the work is to improve the performance of social housing, considering the NBR 15575, through the definition of different envelope solutions, to meet the Level A classification of the Brazilian regulation RTQ-R (Technical Regulation of the Quality of the Energy Efficiency Level of Residential Buildings), and the German Passive House standard, to the climate context of Southern Brazil (bioclimatic zones 1, 2 and 3). Results were analyzed under two approaches: energy and economics. Methodology is divided in 5 steps, in which the EnergyPlus® software was used for the configuration and simulation of the models: 1) analysis of thermal and energetic performance of the model with thermal envelope according to NBR 15575; 2) sensitivity analysis, varying parameters in the thermal envelope of the model, in order to meet the A-level classification, according to RTQ-R; 3) optimization of the thermal envelope of the model configured according to the RTQ-R, through an evolutionary multi-objective algorithm; 4) optimization of the thermal envelope of the model configured according to the standard Passive House; and 5) optimization of the thermal envelope and systems of the model configured according to the Passive House standard. The analysis of the thermal and energetic performance was carried out to analyze the economic viability of the solutions obtained. Conclusion was that the solutions according to the RTQ-R and the Passive House standard provide a great reduction in energy consumption in relation to the solution according to NBR 15575 in the three bioclimatic zones. However, there was a high additional investment for the application of the regulations, with solutions for RTQ-R presenting an additional investment between 26% and 27% and solutions according to the Passive House standard showing an additional investment between 39% and 42%, in the three bioclimatic zones. The RTQ-R solutions were considered viable in bioclimatic zones 1 and 2, where payback was lower than the useful life of the building. Passive House solutions were considered feasible only in bioclimatic zone 2, however, they presented a long payback due to the high cost of the ventilation system with heat recovery.