## 3 Results and Discussion
### Assessment of Circular Economy Strategies

Table 4: Ranking of the importance of CE strategies. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Project Phase**} & \multirow{2}{*}{**CE Strategy**} & \multicolumn{8}{c}{**Participant Responses**} & \multirow{2}{*}{**Mean**} & \multirow{2}{*}{**RII**} & \multirow{2}{*}{**Rank**} & \multirow{2}{*}{**Feasibility Level**} \\ \cline{3-3} \cline{8-13}  & & **A1** & **A2** & **C1** & **C2** & **C3** & **CN1** & **CN2** & **CT1** & **CT2** & **D1** & \\ \hline \multirow{4}{*}{Design for Deconstruction/Dissassembly} & 2 & 3 & 3 & 2 & 3 & 3 & 3 & 3 & 3 & 2 & 2.70 & 0.54 & 10 & Medium \\ \cline{2-13}  & Design for Adaptability and Flexibility. & 3 & 3 & 3 & 2 & 3 & 3 & 3 & 3 & 3 & 3 & 2.90 & 0.58 & 6 & Medium \\ \cline{2-13}  & Design for Standardization. & 3 & 3 & 2 & 3 & 3 & 3 & 2 & 2 & 3 & 3 & 2.70 & 0.54 & 10 & Medium \\ \cline{2-13}  & Design for Unability and Longevity. & 3 & 3 & 5 & 4 & 4 & 4 & 4 & 5 & 5 & 5 & 4.20 & 0.84 & 2 & High \\ \cline{2-13}  & Design for Modularity. & 2 & 3 & 3 & 2 & 4 & 3 & 3 & 2 & 3 & 3 & 2.80 & 0.56 & 8 & Medium \\ \cline{2-13}  & Prefabrication and Offsite Construction. & 3 & 5 & 4 & 4 & 2 & 3 & 3 & 3 & 4 & 4 & 3.50 & 0.70 & 3 & High-Medium \\ \cline{2-13}  & Precuring Reused and Recycled Materials. & 2 & 2 & 2 & 1 & 1 & 2 & 2 & 3 & 2 & 1.90 & 0.38 & 13 & Medium-Low \\ \cline{2-13}  & Prooving Ro-based Materials. & 1 & 2 & 3 & 1 & 1 & 1 & 2 & 2 & 3 & 2 & 1.80 & 0.36 & 15 & Medium-Low \\ \cline{2-13}  & Renewable Energy Integration. & 5 & 5 & 4 & 4 & 4 & 5 & 4 & 5 & 5 & 5 & 4.60 & 0.92 & 1 & High \\ \cline{2-13}  & Adaptive Reuse. & 3 & 3 & 3 & 2 & 2 & 3 & 3 & 3 & 4 & 2 & 2.80 & 0.56 & 8 & Medium \\ \hline \multirow{4}{*}{End of Life} & Reuse of Materials and Products. & 2 & 3 & 3 & 2 & 3 & 2 & 3 & 2 & 4 & 3 & 2.70 & 0.54 & 10 & Medium \\ \cline{2-13}  & Closed-Loop Recycling (up-cycling). & 2 & 3 & 3 & 2 & 3 & 3 & 3 & 3 & 4 & 3 & 2.90 & 0.58 & 6 & Medium \\ \cline{2-13}  & Open-Loop Recycling (down-cycling). & 2 & 4 & 3 & 2 & 3 & 4 & 3 & 3 & 4 & 4 & 3.20 & 0.64 & 4 & High-Medium \\ \cline{2-13}  & Selective Demoition. & 2 & 4 & 3 & 3 & 3 & 3 & 2 & 3 & 4 & 3 & 3.00 & 0.60 & 5 & High-Medium \\ \cline{2-13}  & Deconstruction. & 1 & 2 & 2 & 2 & 2 & 1 & 2 & 2 & 3 & 2 & 1.90 & 0.38 & 13 & Medium-Low \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Ranking of the feasibility of implementing CE strategies in the Saudi Arabian building sector. The top five strategies in terms of importance were as follows: \"Reuse of Materials and Products\" addressing the end-of-life phase (RII = 0.98); followed by three strategies with the same ranking (RII = 0.96): \"Design for Disassembly\", \"Procuring Reused and Recycled Materials\", and \"Renewable Energy Integration\" applicable at the operation and maintenance phase, and, and lastly \"Adaptive Reuse\" at the operation and maintenance phase (RII = 0.94). When considering the feasibility of these strategies, as shown in Table 5, there were noticeable differences in implementation potential. For instance, \"Renewable Energy Integration\", and \" Design for Durability and Longevity\" were not only considered highly important but also stood out as the only two strategies rated as very feasible to implement with RIIs of 0.92 and 0.84, respectively, indicating strong alignment between perceived importance and practical application. Conversely, although \"Procuring Reused and Recycled Materials\" and \"Deconstruction\" were ranked high in importance, they faced significant challenges in feasibility, receiving \"Medium-Low\" feasibility scores (RII = 0.38), which highlights barriers to their adoption. In addition, \"Procuring Bio-based Materials\" reveals a complex perception among participants regarding its importance and feasibility within the CE framework. It received an RII of 0.74, categorizing it as \"High-Medium\" in importance, indicating recognition of its value in promoting circularity in buildings.