## 3 Obstacles to the Implementation of LCA in the Procurement Process of Buildings
### Organizational Obstacles
\begin{table}
\begin{tabular}{l c} \hline \hline
**Organizational Obstacles** & **Reference** \\ \hline _Discussion with stakeholders (owner/client, designer, and contractor) about_ & \\ _EPD implementation_ & \\ _Application of EPDs during the design and construction stage using an office_ & [58] \\ _building as case study_ & \\ \(\rightarrow\) Lack of time to apply an LCA & \\ \hline _Content analysis of the documents obtained from calls for tenders_ & [61] \\ _Comparison of environmental criteria in tenders_ & \\ \(\rightarrow\) Missing knowledge and skill regarding LCA and other GPP tools & \\ \hline _Semi-structured interviews about current practices and obstacles to environmental_ & \\ _requirements in construction_ & \\ _Survey about the existence of municipal policies dealing with environmental issues_ & [62] \\ \(\rightarrow\) Lack of skills related to LCA tools and methods & \\ \hline _Assessment of environmental impacts of two different hot mix asphalt (HMA)_ & \\ _materials to provide evaluation parameter in public bids_ & [93] \\ \(\rightarrow\) Lack of comprehensive approach for application to different civil works & \\ \(\rightarrow\) Lack of green alternatives & \\ \hline _Structured interviews on the assessment of environmental aspects and the review_ & \\ _of environmental requirements_ & \\ _Survey about including environmental requirements in procurement documents_ & [64] \\ \(\rightarrow\) Lack of knowledge of environmental strategies & [64] \\ \(\rightarrow\) Lack of input data & \\ \(\rightarrow\) Lack of expertise in assessing environmental impacts & \\ \hline _Assessment of the determinants and drawbacks of green procurement adoption_ & \\ \(\rightarrow\) Lack of training for employees & [65] \\ \(\rightarrow\) Difficulties in the preparation of tenders and purchases & \\ \(\rightarrow\) Lack of information about environmental impacts & \\ \hline _LCA is applied to wood windows to support procurement criteria definition_ & [66] \\ \(\rightarrow\) Lack of appropriate data & \\ \hline _Literature review of obstacles and drivers for sustainable buildings_ & \\ _Interviews about obstacles and drivers for sustainable buildings_ & \\ _Case studies on improving the sustainable building process and the impacts and_ & \\ _benefits of sustainable buildings_ & \\ \(\rightarrow\) Insufficient knowledge to develop clear targets and mitigating strategies & \\ \(\rightarrow\) Contractors are not able to explain the sustainability criteria & [67] \\ for subcontractors & \\ \(\rightarrow\) Client lacks an actor who supports him in setting targets for & \\ sustainability requirements & \\ \(\rightarrow\) No resources to supervise the realization of sustainability requirements & \\ \(\rightarrow\) Not enough time to compare alternatives & \\ \hline _Interview series to achieve insights into application of environmental preferences_ & \\ _in construction projects_ & \\ _Survey about the application of environmental preferences in the procurement_ & \\ _of construction contracts_ & [68] \\ \(\rightarrow\) Fear of high- and time-consuming bureaucracy & \\ \(\rightarrow\) Insufficient knowledge & \\ \(\rightarrow\) Fear of project delays & \\ \hline _Assessing the environmental impact of road works to promote green procurement_ & \\ _using multi-criteria analysis_ & \\ \(\rightarrow\) Lack of knowledge connected with LCA & [90] \\ \(\rightarrow\) Technical and organizational difficulties during the management & \\ of green tenders & \\ \hline _LCA is applied for two products to support procurement decision_ & \\ \(\rightarrow\) Additional time effort for LCA application & [91] \\ \(\rightarrow\) Lack of know-how in the field of LCA & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Organizational obstacles to LCA implementation in the procurement process of buildings. Among the organizational obstacles, the additional time required to conduct LCAs in the procurement process was cited as an implementation barrier. This obstacle cannot be completely eliminated, as additional tasks usually require additional time.