## 6 Conclusions  
The construction industry, which is among the industries with the least amount of digitalization, can significantly benefit from digitalized solutions. The 3 DCP technology is one of the digitalization methods that has notable implications for construction efficiency. In this research, we calculated the cost and completion time differences for a housing construction project using different methods, supply chain configurations, and designs. We excluded the parts of the process maps that were identical for all scenarios, such as the foundation slab work, roofing, painting, and tiling. This research illustrated that 3 DCP is both time- and cost-competitive with on-site conventional construction. More specifically, we found that the cost of on-site conventional construction methods for round houses is more than two times higher than that of on-site 3 DCP for the same design. This suggests that 3 DCP is more cost-efficient for the construction of round walls. Similarly, while comparing the cost of the on-site conventional construction method for the rectangular design and on-site 3 DCP for the same design, we observed a 80.1% higher cost for the on-site conventional construction method. The cost efficiency of 3 DCP was related to the lack of formwork, which reduced the material costs significantly and also decreased the cost of labor. We also found that, although complex design proved to be costly for conventional construction, for 3 DCP, it had positive effects on the efficiency and process time. On-site 3 DCP proved to be significantly more time-efficient than the other scenarios due to the elimination of assembly work and the fact that drying could take place on-site while other activities were being performed concurrently. This is interesting since prefabrication is known to be cost-effective and time-efficient, but 3 DCP proved to be a worthy competitor. The contributions of this research are threefold:  
1. The cost and time competitiveness of conventional construction methods versus 3 DCP was evaluated;
2. The impact of the design on the cost and time efficiency of 3 DCP was analyzed;
3. The impact of supply chain configurations (off-site versus on-site construction) on the cost and process time competitiveness of 3 DCP was uncovered. This research was limited to investigating the effects of house design variations. Moreover, we did not study gantry-based 3 DCP. Future research must focus on case studies of real-world designs, cost and schedule comparisons for different 3 DCP methods, and comparisons with a wider range of traditional construction methods. Conceptualization, S.H.K., Y.W. and M.L. ; methodology, S.H.K., J.H., M.T., A.M. and A.P. ; software, A.M.; validation, S.K, A.M., M.T. and A.P. ; formal analysis, S.H.K., M.T., and A.P. ; investigation, S.H.K., Y.W., J.H., M.T., A.M., A.P. and M.L. ; resources, A.M.; data curation, S.H.K. ; writing--original draft preparation, S.H.K., M.T., A.M. and A.P. ; writing--review and editing, S.H.K., Y.W., J.H., M.T., A.M., A.P. and M.L. ; visualization, A.M.; supervision, S.H.K. ; funding acquisition, J.H. and A.P. All authors have read and agreed to the published version of the manuscript. **Funding:** This research was funded by ACADEMY OF FINLAND, grant number 323831. **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable. **Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. **Appendix A**  
**Table A1. ** The architectural 3D model of the cases. The buildings' dimensions and specification:  
The thickness of external walls is 230 mm and the thickness of internal walls is 110 mm. The height of the walls is 2.5 m. The density of walls made by 3 DCP in this research is assumed to be 40%.