# A Case Study on Integrating an Eco-Design Tool into the Construction Decision-Making Process
## 3 Results and Discussion  
### Case Study: Comparison of Window Frame Solutions  
Tables 1-3 show data sourced from the EPD of the window frame solutions considered here. The three selected EPDs could be directly compared because they follow the same standard and possess the same functional unit and system boundaries (Table 1). In addition, the publication and expiry dates were consistent with the period of analysis (2023/2024). Table 4 shows the normalized environmental impacts of different window frame solutions. The normalized environmental impacts were computed by the eco-design tool, and the resulting radar chart can be seen in Figure 2. \begin{table}
\begin{tabular}{l c c c} \hline
**Parameters** & \multicolumn{3}{c}{**Case: Window Frame Material**} \\ \hline Code & A11 & A22 & A33 \\ Material/solution & PVC & Aluminium & Wood \\ Classification & New & New & New \\ Registration program & INIES & INIES & INIES \\ DAP registration code * & - & - & - \\ ECO platform code * & - & - & - \\  & EN & EN & EN \\ Standard & 15804:2012+A1:2013 & 15804:2012+A1:2013 & 15804:2012+A1:2013 \\  & [21] & [21] & [21] \\ Publication date & January 2021 & October 2022 & November 2022 \\ Expiring date & January 2026 & October 2027 & November 2027 \\ Manufacturer * & A & B & C \\ Region & France & France & France \\ Description & PVC window frame & Aluminium window & Wooden window \\ Functional unit & m\({}^{2}\) & m\({}^{2}\) & m\({}^{2}\) \\ System boundary ** & A/B/C/D & A/B/C/D & A/B/C/D \\ Recycled materials & No & Yes & No \\ Incorporated recycled & - & Aluminium & - \\ material & & & \\ \hline \end{tabular}  
* Commercial details have been intentionally omitted by the authors. ** A—production stage and construction process stage; B—use stage; C—end-of-life stage; D—benefits and load.  
\end{table} 
Table 1: Sourced data of different window frame solutions. \begin{table}
\begin{tabular}{l c c c} \hline
**Parameters** & \multicolumn{3}{c}{**Case: Window Frame Material**} \\ \hline Code & A11 & A22 & A33 \\ Material/Solution & PVC & Aluminium & Wood \\ GWP (kg CO\({}_{2}\) equiv.) & \(5.17\times 10^{1}\) & \(6.03\times 10^{1}\) & \(5.27\times 10^{1}\) \\ ODP (kg CFC 11 equiv.) & \(2.35\times 10^{-6}\) & \(5.57\times 10^{-6}\) & \(6.62\times 10^{-6}\) \\ AP (kg SO\({}_{2}\) equiv.) & \(2.65\times 10^{-1}\) & \(1.91\times 10^{-1}\) & \(2.03\times 10^{-1}\) \\ EP (kg (PO\({}_{4}\))\({}^{3-}\) equiv.) & \(4.70\times 10^{-2}\) & \(1.07\times 10^{-1}\) & \(7.11\times 10^{-2}\) \\ POCP (kg C\({}_{2}\)H\({}_{4}\) equiv.) & \(1.34\times 10^{-2}\) & \(2.14\times 10^{-2}\) & \(1.40\times 10^{-2}\) \\ ADPE (kg Sb equiv.) & \(2.24\times 10^{-3}\) & \(1.28\times 10^{-3}\) & \(1.31\times 10^{-3}\) \\ ADPF (MJ, N.C.V.) & \(9.03\times 10^{2}\) & \(8.64\times 10^{2}\) & \(6.41\times 10^{2}\) \\ \hline \end{tabular}  
* \(\overline{\text{GWP}}\)—global warming potential—total; ODP—ozone depletion; AP—acidification; EP— eutrophication; POCP—photochemical ozone formation; ADPE—abiotic depletion—non-fossil resources; ADPF—abiotic depletion potential—fossil resources; N.C.V.—net calorific value.  
\end{table} 
Table 2: Environmental impacts of different window frame solutions. The results show that the different window frame solutions present very distinct impact profiles. Aluminium window frames display the highest global warming potential (GWP), eutrophication (EP), and photochemical ozone formation (POCP), whereas PVC and wood window frames presented the lowest impact in different impact categories. Aluminium window frames presented a total impact area of 2.05 m\({}^{2}\), while PVC and wood window frames display similar impact areas of 1.51 m\({}^{2}\) and 1.56 m\({}^{2}\), respectively. These results demonstrate that selecting aluminum window frames entails higher environmental