## 6 Conclusions
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Evaluated Data** & & **Findings and Results** & \\ \hline \multirow{4}{*}{\begin{tabular}{c} All Data (without \\ using the approach) \\ \end{tabular} } & Old homes (built before & \multirow{4}{*}{\begin{tabular}{c} Improving energy \\ efficiency is achieved \\ by installing insulation \\ in the roof of \\ residential buildings. \\ \end{tabular} } \\  & & & \\  & & & \\ \hline \multirow{4}{*}{\begin{tabular}{c} Low-consumption \\ cluster \\ \end{tabular} } & & & \begin{tabular}{c} Not using tariff 7 leads to \\ better energy efficiency. \\ Using the tariff leads to \\ poor energy efficiency in \\ small and old houses \\ (less than 51 m\({}^{2}\)). \\ (new finding) \\ \end{tabular} & \begin{tabular}{c} Improving energy \\ efficiency is achieved \\ by installing insulation \\ in the roof of \\ residential buildings. \\ \end{tabular} \\ \hline \multirow{4}{*}{\begin{tabular}{c} Medium-consumption \\ cluster \\ \end{tabular} } & & \begin{tabular}{c} Flats have a more \\ favorable energy \\ efficiency; even \\ newly-built flats. \\ (new finding) \\ Old homes in Wales \\ which have a detached \\ structure, and have \\ installed boilers have a \\ good energy efficiency. \\ (new finding) \\ \end{tabular} & \begin{tabular}{c} Using this tariff leads to \\ a better energy efficiency \\ in big (over 151 m\({}^{2}\)) and \\ old houses. \\ (new finding) \\ \end{tabular} \\ \hline \multirow{4}{*}{\begin{tabular}{c} High-consumption \\ cluster \\ \end{tabular} } & \begin{tabular}{c} Installing boilers leads to \\ a better energy efficiency. \\ In mid-terrace and \\ end-terrace structures, \\ boilers lead to better \\ energy efficiency. \\ (new finding) \\ \end{tabular} & \
\begin{tabular}{c} The newly constructed \\ flats have the best \\ efficiency. \\ (new finding) \\ \end{tabular} &
\begin{tabular}{c} Households living in \\ Wales have better \\ energy efficiency. \\ (new finding) \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Assessing the results of the proposed approach. that in the low-consumption cluster, old and small houses (less than 51 m\({}^{2}\)) that use this tariff have a poor energy efficiency. Also, among the old and big houses (over 151 m\({}^{2}\)) of the medium-consumption cluster using this tariff has a positive impact. The approach shows that the home structure influences energy efficiency. In the high-consumption cluster, installing boilers in mid-terrace and end-terrace structures, and detached structures in Wales in the medium-consumption cluster, leads to better energy efficiency. In the medium-consumption cluster, it was seen that flats are better in energy efficiency than other structures, even compared to newly-built houses. Different geographic regions also had a different behavior. The high-consumption cluster shows better energy efficiency in the houses in Wales. Definitely, having more comprehensive and adequate information of the different regions of England and Wales could extract more knowledge. The accuracy of modeling in the approach presented was better than modeling without it and detailed findings can be discovered. Through its new and in-depth results, this approach has shown that it is capable and beneficial in the field of retrieval knowledge. These new findings demonstrate that we cannot make a similar decision for all homes. As homes in a cluster have their unique behavior, policies and decisions must be unique for them. The knowledge obtained is suitable and useful for residential buildings of similar features and nature to plan and upgrade energy efficiency, and also to improve EPCs.