Eco-design of renovation project
Renovation or new construction? Cycleco compared the environmental performance of the two options and shares his initial conclusions.
Cycleco and Etamine worked together on environmental comparison of rehabilitation solutions. The case study is an old building of collective housing in an urban area, with 2500m² of floors. Only the supporting structure and the floors are conserved. Two solutions for the building owner: major rehabilitation or demolition and new construction.
This study aimed at assessing precisely the environmental impact of each solution. For the solution of reconstruction for example, a distinction is made between the residual impact of the building to be demolished (this refers to the waste of still functional materials that are destroyed; in the case study: the supporting structure), the impact of the new construction materials, demolition and end of life (eol) of the old building, the reconstruction, the use for 60 more years, and finally the demolition and end of life of the building in 60 years. The following figure shows the comparison of both scenarios on the impact on climate change as well as details of the distribution of the impacts.
Comparison of scenarios and repartition of impacts
It is found that the impact of the use (energy consumption for heating, lighting, etc.) is the most important, followed by the new construction materials. The impact of the projects and the residual impacts of the building to be demolished are very low in comparison. Thus energy efficiency remains the key factor regarding impact on climate change. Therefore the reconstruction solution is preferable to the rehabilitation when it has a gain of energy performance. In this case study of large-scale renovation, as only the supporting structure is retained, if the reconstruction is from 5 to 10kWh/m².year more efficient, then it is preferable to rehabilitation.
This project complements Cycleco’s experience on life cycle assessment of renovation. More information on other projects:[list style="list-img2"] PUCA-REHA contest, “Cycleco partenaire du projet Tekhnê, lauréat du programme REHA 2″ and “Cycleco cited in ” Le Moniteur ” ” on ekoconception.eu or http://www.reha-puca.fr/IMG/pdf/2013_moniteur_reha.pdf [/list] [list style="list-img2"] iNSPiRe : «Cycleco partenaire du projet FP7 INSPIRe» on ekoconception.eu or inspirefp7.eu [/list]