## 4 Results
### Energy Demand According to the Energy Simulation  
To obtain the results of annual energy demands for all 6 scenarios and establish a comparative analysis between them, the methodology set out in Section 3.5 was followed, using the Design Builder tool. The model was first calibrated according to the climate data obtained in situ. Internal boundary conditions can be defined in three ways in DesignBuilder CFD. In this paper, surface temperatures are being defined for all zone surfaces. Temperature sensors were installed in each layer of the roof enclosure to measure the temperature variation in each of them. The way to accurately include the effect of radiation heat transfer in CFD calculations is to run an EnergyPlus simulation first, to compare with real monitoring data obtained and then import surface temperatures from the EnergyPlus simulation results as CFD boundary conditions. Figure 11 shows the monitoring data obtained for the flat. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{2}{c}{**Loft Flat Roofs. Housing Block**} & \multicolumn{3}{c}{**Exhibition Hall Roofs. MUA**} \\ \hline \hline \multirow{2}{*}{Sections} & \multicolumn{2}{c}{**Thermal Admittance Y11, Y22**} & \multirow{2}{*}{\begin{tabular}{c} \\ \end{tabular} } \\  & \multicolumn{2}{c}{\begin{tabular}{c} Internal \(Y_{11}\), \\ \end{tabular} } \\  & \multicolumn{2}{c}{\begin{tabular}{c} Internal \(Y_{11}\), \\ \end{tabular} } \\  & \multicolumn{2}{c}{\begin{tabular}{c} Sections \\ \end{tabular} } & \multicolumn{2}{c}{\begin{tabular}{c} External \(Y_{22}\), \\ \end{tabular} } \\  & \multicolumn{2}{c}{\
\begin{tabular}{c} Internal \(Y_{11}\), \\ \end{tabular} } \\  & \multicolumn{2}{c}{
\begin{tabular}{c} \(\left(\mathrm{W/m^{2}K}\right)\) \\ \end{tabular} } \\ \hline Q\({}_{\mathrm{R}}\)\_1 & 3.947 & 5.766 & Q\({}_{\mathrm{M}}\)\_1 & 9.471 & 2.282 \\ Q\({}_{\mathrm{R}}\)\_2 & 4.335 & 5.766 & Q\({}_{\mathrm{M}}\)\_2 & 6.454 & 2.342 \\ Q\({}_{\mathrm{R}}\)\_21\_0.15 & 9.392 & 5.751 & Q\({}_{\mathrm{M}}\)\_21\_0.15 & 9.392 & 2.344 \\ \hline \hline \end{tabular}
\end{table} 
Table 14: Internal and external thermal admittance values. Figure 11: Left flat. Q\({}_{\mathrm{R}}\)\_1. Temperature data obtained by monitoring, 1–7 August 2014. The second and final step was adjusting the values of ventilation or the interior air renewal and air infiltrations throughout the building envelope [71]. This was made possible using the data obtained from the meter on monthly energy consumption throughout 2014. In the case of the MUA Sempere Hall, annual consumption w 63.100 MWh/year, which--given that the useful area surface was 366 m\({}^{2}\) and deducting the lighting values of 2.8 kWh/m\({}^{2}\)year--accounted for an energy demand of 117.760 kWh/m\({}^{2}\)year. Although the value of the renewal air flow for 110 people according to the CTE is 3 aCH, the actual flow through the HVAC system measured in situ is 3130-3625 m\({}^{3}\)/h, so it varies between 1.90 and 2.20 aCH, depending on the external climatic conditions. The installation was designed with air renewal values lower than those required in CTE DB HS3, since the real average occupation of the Sempere Room is much lower than 0.3 people per m\({}^{2}\). Thus, a value within this interval was applied in this simulation according to the calibration method. It was adjusted to the value of annual energy demand, to match actual consumption per meter, obtaining a renewal air value of 1.95 aCH and infiltration air of 0.45 aCH. In the flat, meter consumption accounted for 7.447 MWh/year, with an annual energy demand of 60.06 kWh/m\({}^{2}\)year; air renewal values of 0.77 aCH and air infiltration through the envelope amounted to 0.23 aCH. In this way, the model was calibrated, adjusted to the annual energy demands obtained from the meter.