# End-of-Life Scenarios for Mass Timber: Assumptions, Limitations and Potentials--A Literature Review
## 3 Results
### Cascading Use for EoL: Non-Demolition, Reuse, Recycling, Energy Recovery and Landfill
#### 3.6.2 Difficulties in Implementing Cascading Uses of Wood  
Even if the cascading use of wood could contribute to limiting climate change, the current building industry continues to follow a wasteful approach, with CDW accounting for 35% of global waste disposed of in landfills [61]. The barriers of optimizing CDW in EU are summarized by [PERSON] et al. [62] into a list of factors, including the perceived high cost of reuse and recycling relative to \"lower-value\" treatment options such as incineration and landfilling, the lack of local market, policy challenges such as chemical composition or safety regulations, and competition with low-cost products. Disposal in landfills is often the most cost-effective and convenient option. In addition, the market could project lack of confidence in the quality of recycled materials. [PERSON] et al. [45] have also stated that the current existing building stock is not designed for deconstruction, which is still driven by economic factors such as time and cost. However, selective dismantling for reuse and recycling could be achieved by bringing up the cost for disposal, transport and new raw materials. Therefore, policies, market and the industry are all responsible in implementing cascading use of wood. The public perceptions of circular use of wood are also investigated by other scholars. [PERSON] et al. [58] conducted surveys to explore the attitudes of the general public and professionals towards prolonging the life cycles of wood products through cascading in central and southeastern Europe. The study found that the end-of-life options for wood are still being developed in certain parts of Europe in comparison to the few leading organizations and associations mainly located in western Europe. Many of the sustainable processes must be better explained with detailed education and policy support involved. Implementation will take time since the industry and market in other parts of Europe--specifically Bosnia and Herzgeovina, Croatia, Serbia, and Slovenia, where the survey was conducted--do not sufficiently understand the cascading concept. Additionally, policies and systems lack incentives to adopt a fully circular approach to wood utilization [58]. The lack of knowledge about the circularity of wood products can be a global issue, particularly in regions where public perception is closely tied to economic growth and constrained policymaking. However, this could be interfered with by implementing new regulations and policies on the control of carbon footprint for building projects. So far, all Nordic countries have started regulations on the requirement of carbon footprint documentation in new buildings, and have set life cycle carbon limits for buildings at certain scales [23]. These measures set precedents in pushing for low-carbon building materials and construction techniques from top-down perspectives. As a result, more circular strategies and materials can be taken into consideration through building design, construction, and management throughout their life cycles. Thus, the perception of the circular use of wood by the public and the market could be shaped by sustainable policies. Several researchers have also pointed out the difficulties in assessing the impact with the cascading EoL of wood within the LCA framework. This is because multi-output cascading systems could be challenging due to the involvement of multiple products and recycling steps of wood, as well as the difficulty in distributing emissions, especially biogenic CO\({}_{2}\), over extended time periods [36]. They also acknowledged that the accounting of carbon flows is dynamic. Although it was concluded that longer cascade chains offer greater benefits compared to shorter ones in terms of biogenic CO\({}_{2}\) emissions, it still remains unclear how to distribute the burdens and benefits of recycling materials across their cascading uses within LCA [36; 63].