SENSITIVITY ANALYSIS APPLIED ON BUILDING SIMULATION IN EARLY DESIGN STAGES

Resumo

The complexity of the building simulation task, including time consumed for modeling, testing, quality assurance and reporting is a difficulty to insert this practice in the early design stages of buildings. In this paper, building simulation was conducted to support design team to define strategies for energy efficient façade in an office Building in São Paulo, Brazil. The project was designed for LEED® certification in Core and Shell category. A sensitivity analysis was carried out through EnergyPlus simulation to help the architect to define the parameters: window-to-wall ratio; type of glass; the use of spandrel glass and wall construction. A simplified building model was developed to conduct the simulation in the early design stage. A total of 132 cases were simulated and the results were selected according to the energy savings achieved against the baseline building, according to ASHRAE Standard 90.1 approach. The use of fully glazed façade has become common in Brazil. Such strategy has been always criticized, as in tropical climate, the solar heat gain through windows is very significant to cooling loads. The sentivity analysis resulted in building models with energy savings varying from 5% to 11%. This work confirms that the façades of this type of building, with solar selective glazing system, high performance HVAC and lighting systems, have less impact on annual energy consumption than conventional building, with clear glass and low efficiency systems.