On the ranking criteria for energy retrofitting building stocks: Which building goes first? The role of the building size in the establishment of priority lists

The energy retrofit of the existing building stocks is considered a preeminent strategy to lowering the energy consumption of the building sector. Other than the definition of the most successful combination of energy saving measures, the definition of a suitable ranking of all the buildings of the stock, on which implementing established energy retrofit measures, is quite a relevant issue. The most eligible criterion for prioritizing the buildings seems their energy consumption because it combines the building energy performance and their size. To investigate the role played by the building dimension in determining the order of priority of all the buildings of a given stock, this paper presents and compares different hierarchical orders of 25 existing buildings that were obtained with and without consideration of the size of the buildings. Results show that, when the size of buildings is covered in the calculations, the generated prioritized order differs significantly. In addition, it has found that the entity of the variations compared to the hierarchy that does not contemplate the size of buildings, is logarithmically correlated with the net surface. Additionally, some concerns have arisen regarding the role of the EP index for the building energy classification.