# Life Cycle Analysis Challenges through Building Rating Schemes within the European Framework
## 3 Results
### Expert Interviews
This is not sufficient to draw conclusions but gives a hint to the consistency of LCA-aggregated results, which are used by the taxonomy and the Nordic countries [80]. Concerning the mapping-gap analysis, some insights were identified by the experts. Firstly, not everyone was fully acquainted with the second version published in October 2020. All had been involved in the test phase between the first and second versions and were aware of the improvements. All agreed that many improvements in the second version can be credited to the dialogue between the BRS and the Level(s) development teams at DG Env and JRC. In practical terms, it means that the results presented are not fully updated to the second version. This does not affect the validity of the results. The gaps identified in the analysis were welcomed by the experts, who suggested future improvements within their respective BRS. For indicators 1.2 and 2.4, filling in these gaps means to add impact categories, add result interpretation, adjust cut-off rules, adjust reference study periods, and in the case of BREEAM-NL, adjust life cycle stages. Finally, for indicator 6.1, there is a need for all to adjust discount rates, reported costs, and add scenarios. The issue of the reference study period remains open. British and Irish cultures favour a 60-year period, but continental Europe marks 50 years for the use-stage of a building and is thus applied in LCA calculations. The first version of Level(s) used 60, but after the test phase, the second version functions with a 50-year study period. This reduction influences final LCA values. Furthermore, the question of making all life cycle stages as well as all impact categories mandatory remains open. While carbon metrics are best known and accepted, and climate mitigation uses GWP and GHG in CO\({}_{2}\) eq units as a star indicator, buildings have equally dire impacts on acidification, ozonification, and very clearly on abiotic resource depletion, including minerals, metals, and fossil fuel. In addition, its water footprint is well known but seldom included in LCA. Last, but not least, the GWP of land use and change (LULUC) might be as important as the energy-related GWP. The common understanding is that GWP acts as a spearhead for all the other impacts wherever relevant. Including all stages is more easily solved. In the detailed mapping and in Table 4, it is clearly identified how all BRS except BREEAM demand all stages for the best rated buildings. The effort to calculate LCA for all stages, as well as to include all impact categories, is high and might not be needed for early design. Once more, the three entry levels of Level(s) make sense. A final issue that arose during the interviews was that related to including all building elements in the LCA calculation, only BREEAM-NL failed to solve this, at least for the best rating. It is commonly agreed that it is not enough to include a few materials with EPD. Even all materials with EPD would not necessarily lower the LCA result. The life cycle of all building materials and elements should be analysed to call it a \begin{table}
\begin{tabular}{l l l} \hline \hline
**Averages** & **PED (kWh-m\({}^{-}\)2-yr\({}^{-}\)1)** & **GWP (CO\({}_{2}\) eq\(\cdot\)m\({}^{-}\)2-yr\({}^{-}\)1)** \\ \hline
**NF-HQE** & N/A & N/A \\ \hline
**VERDE** & 29.22 & 40.49 \\ \hline
**DGNB** & 61.10 & 18.22 \\ \hline
**BREEAM NL** & Between 25 and 40 & Between 15 and 35 \\ \hline
**HPI** & \textless{}42 & \textless{}300 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Average PED and GWP per BRS. building LCA. This raised another challenge, namely the insufficient availability of data, which are the very basis of LCA. The MLP methodology was not known to any of the interviewees. The GBCs, where they are active, are, in fact, key agents in the transition. This was well understood and accepted. Nevertheless, while acknowledging a positive recent evolution, all informed that their national markets offer resistance. They identify themselves as pioneers.