## 3 Results
### Obtained Data and Validation  
#### 3.1.1 Validation of the Initial Building Construction  
In this case, information such as dimensions, typology of holes and carpentry, domestic hot water (DHW) facilities, boilers and heating installations--among others--were the main input data into the CE3X software. In particular, for all the certifications done, it was defined--for a static value of dry temperatures--to obtain the results of the energy certification shown Figure 7. In this case, the results showed an amount of a total primary energy consumption of 224,500 kWh/m\({}^{2}\) year. What is more,  
Figure 6: Building objective of this study.  
from the data obtained from the CE3X unified tool, a consumption distribution of 173,410 kWh/m\({}^{2}\) year for heating and 51,040 kWh/m\({}^{2}\) year for DHW was observed in Figure 8.  
After this initial analysis, the next step was to carry out the same automatic calculation procedure of the ISO 13790 standard by spreadsheets and validate the obtained results with the CE3X certification. In particular, it is interesting to highlight that the input data used in the spreadsheet are identical to those used with CE3X and the differences obtained are minimal, as we can observe in Table 1. At the same time, the real sample data showed that the information available only corresponds to fuel consumption for heating and reaches amounts to 74,910 kWh/m\({}^{2}\) year. Finally, Table 1 shows a sum up of the different analysis for the same building construction.  
This Table 1 showed an actual consumption much lower than the estimated data of the 177,410 kWh/m\({}^{2}\) year from the CE3X software. The reason why the energy consumption was not in agreement with the certified software resources indications are only the difference of occupation levels between the average expected by the standards and the real occupation. It implies a change in the liters per day of hot water and the real air changes in residential buildings being this effect explained in depth in the section \"H.3. Analysis of errors of the ISO 13790\". In particular, in agreement with this H3 section, the half of the obtained energy consumption of the software resources (86,705 kWh/(m\({}^{2}\)-year)) are similar with the real sampled primary energy 74,910 kWh/(m\({}^{2}\)-year).  
As it was explained before, this is a consequence of to employ average occupation values (Tabulated in the standard) instead real occupation, which is lower in this case for the particular characteristics of their occupants. Despite this, the aim of the work is to show a new methodology for decision making and, this is a certified software by the Spanish Ministry considering standard conditions.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Primary Energy Consumption** & & **Real Sampled Data** \\
**(kWh/(m\({}^{2}\) year))** & **CE3X** & **ISO 13790** & **(Previous Retrofitting)** \\ \hline Heating & 173,410 & 173,200 & 74,910 \\ Domestic hot water & 51,040 & 51,020 & \\ Total & 224,500 & 224,300 & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Calculation procedure validation and actual energy consumption.  
Figure 8: Energy certification from CE3X software.  
Figure 7: Energy certification of the building.  
In consequence, this difference respect real sampled data is not so important for this study and it is of more interest to compare the main results with both software resources (CE3X and ISO 13790 of our calculation procedure).