Methodology to enhance the Portuguese thermal regulation accuracy for existing buildings

The goal of this study is to evaluate the accuracy of the Portuguese thermal regulation simplified methodology for existing buildings and to assess the influence of different parameters on the building final energy performance evaluation. Simple “in-situ” measurement techniques were carried out to calibrate the input data in this methodology. The results obtained with the simplified methodology, with and without the input data calibration, were compared with the results obtained with the detailed methodology and it was concluded that the “in-situ” calibration could contribute to improve the accuracy of the energy needs estimation and that the simplified methodology results are, in average, 11% higher than the detailed methodology.