## 3 Results
### Energy Demand
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Building Type**} & \multirow{2}{*}{**Year**} & \multirow{2}{*}{
\begin{tabular}{c} **Climate** \\ **Zone** \\ \end{tabular} } & \multicolumn{4}{c}{**Surface U-Value (W/m\({}^{2}\)-K)**} & \multicolumn{2}{c}{**AUg**} & \multirow{2}{*}{\(\mathbf{g}_{\bot}\)} & \multirow{2}{*}{\(\mathbf{c}_{100}\)} & \multirow{2}{*}{\(\mathbf{ns}\)} \\ \cline{3-3} \cline{6-10}  & & & & **Wall** & **Roof** & **Floor** & **Window** & **(W/m\({}^{2}\)-K)** & **(\(\mathbf{m}^{2}\)/h\(\cdot\)m\({}^{2}\))** & **(\(\mathbf{n}^{-1}\))** \\ \hline \multirow{6}{*}{Detached} & \multirow{6}{*}{1979} & A & 1.43 & 1.12 & 1.59 & 4.05 & & & 30.9 & 18.5 \\  & & B & 1.11 & 0.86 & 1.23 & 3.13 & & & & 30.9 & 18.5 \\  & & C & 0.93 & 0.70 & 1.05 & 2.84 & 0.21 & 0.83 & & & 28.2 & 16.8 \\  & & D & 0.86 & 0.56 & 0.92 & 2.76 & & & & & \\  & & E & 0.84 & 0.42 & 0.95 & 2.68 & & & & & \\ \cline{2-10}  & \multirow{6}{*}{2019} & A & 0.35 & 0.26 & 0.41 & 2.72 & 0.08 & 0.72 & & & \\  & & B & 0.36 & 0.28 & 0.39 & 2.38 & 0.08 & 0.70 & & & \\  & & C & 0.20 & 0.17 & 0.24 & 1.82 & 0.21 & 0.66 & 10.1 & 6.0 \\  & & D & 0.19 & 0.15 & 0.19 & 1.40 & 0.21 & 0.63 & & & \\  & & E & 0.27 & 0.23 & 0.27 & 1.51 & 0.08 & 0.64 & & & \\ \hline \multirow{6}{*}{Attached} & \multirow{6}{*}{1979} & A & 1.71 & 1.33 & 1.90 & 4.84 & & & 32.0 & 9.0 \\  & & B & 1.32 & 1.03 & 1.47 & 3.73 & & & 32.0 & 9.0 \\  & & C & 1.10 & 0.83 & 1.24 & 3.37 & 0.18 & 0.83 & & & \\  & & D & 1.03 & 0.66 & 1.10 & 3.30 & & & 27.7 & 7.8 \\ \cline{2-10}  & & E & 1.01 & 0.51 & 1.15 & 3.22 & & & & & \\ \cline{2-10}  & \multirow{6}{*}{2019} & A & 0.35 & 0.27 & 0.42 & 2.73 & 0.05 & 0.72 & & & \\  & & B & 0.37 & 0.29 & 0.40 & 2.44 & 0.05 & 0.70 & & 17.6 & 5.0 \\  & & C & 0.23 & 0.19 & 0.26 & 1.90 & 0.17 & 0.67 & & & \\  & & D & 0.32 & 0.27 & 0.32 & 1.92 & 0.05 & 0.67 & 15.0 & 4.2 \\  & & E & 0.19 & 0.15 & 0.19 & 1.31 & 0.17 & 0.62 & & & \\ \hline \multirow{6}{*}{Semi-detached} & \multirow{6}{*}{1979} & A & 1.51 & 1.18 & 1.68 & 4.27 & & & & 31.4 & 12.9 \\  & & B & 1.17 & 0.91 & 1.30 & 3.30 & & & & 31.4 & 12.9 \\ \cline{1-1}  & & C & 0.98 & 0.73 & 1.10 & 2.99 & 0.18 & 0.83 & & & \\ \cline{1-1}  & & D & 0.91 & 0.58 & 0.97 & 2.90 & & & & 28.0 & 11.5 \\ \cline{1-1}  & & E & 0.88 & 0.44 & 1.00 & 2.81 & & & & \\ \cline{1-1} \cline{2-10}  & \multirow{6}{*}{2019} & A & 0.34 & 0.26 & 0.41 & 2.71 & 0.06 & 0.72 & & & \\ \cline{1-1}  & & B & 0.36 & 0.28 & 0.39 & 2.40 & 0.06 & 0.70 & & & \\ \cline{1-1}  & & C & 0.22 & 0.18 & 0.25 & 1.88 & 0.18 & 0.67 & 14.6 & 6.0 \\ \cline{1-1}  & & D & 0.30 & 0.25 & 0.30 & 1.86 & 0.06 & 0.67 & & & \\ \cline{1-1}  & & E & 0.28 & 0.24 & 0.28 & 1.54 & 0.06 & 0.64 & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 5: \(Cont.\)single-family homes and is underlined in Figures 2 and 3. These two figures show the simulation results for each building model at the reference conditions. In Figure 2, we can observe with detail the expected heating demand range for the Spanish reference buildings, as well as the wide range of heating demand values of 1979  
Figure 3: Cooling demand at reference set-point temperature for each building model and construction year in peninsular Spain. Figure 2: Heating demand at reference set-point temperature for each building model and construction year in peninsular Spain. buildings compared with the latest buildings. This highlights the impact of improving the thermal envelope and the importance of incentivising building renovation, especially in a scenario where less than 2% [57] of the existing buildings were constructed under Directive 2010/31/EU, and 55% of Spanish buildings were built prior to the 1979 Building Technical Code [58]. Similarly, in Figure 3, one can observe the impact of improving the thermal envelope on the reduction of cooling demand.