PURKU - demolition as part of urban development - eco-efficient utilization of demolition materials in infrastructure and real estate construction

In the planning area, construction starts more and more often with the demolition of old buildings. A total of 85 % of construction and demolition waste is generated from renovation projects and the demolition of buildings, and the remaining 15 % from new construction. As a member of the EU, Finland was committed to utilizing 70 % of construction and demolition waste by 2020. However, our current utilization rate is still below 60 %. Attention must therefore be paid to the utilization of demolition materials.

When construction begins in a planned area, the old existing building stock typically must be demolished, meaning that easily accessible areas for building in urban areas have been built on at least once. At the same time, streets, pedestrian paths, parking areas, waterfront structures, noise barriers, etc. are being built and renovated on or near the sites, where the aggregates from the demolition sites could be utilized on site more efficiently than currently possible and in a way that minimizes the transportation of materials. This would bring significant financial savings in logistics, especially for heavy transport, but would also reduce environmental impacts such as heavy traffic emissions, the burden on the city's street network, and the need for virgin materials and raw materials. It would also improve traffic safety in urban areas by reducing congestion and the number of large vehicles.

The PURKU project develops a completely new value chain for construction, which starts with demolition as part of the beginning of the value chain and life cycle models. Traditionally, demolition is the end point of construction. During the project, new methods will be studied and tested at pilot sites as part of the demolition site's operating procedures. Particular attention will be paid to new working methods that crush aggregates for reuse at or near the site without transporting the materials away from the demolition site for processing and back again after processing. Demolition pilots monitor the amount of crushing dust, noise and vibration and develop methods to combat them. The laboratory studies demolition materials that cannot currently be utilized, for example, making asbestos fibres harmless. In addition, the aim is to build a test field where demolition rock materials are utilized. The work is divided into seven work packages, the purpose of which is that at the end of the project, there will be a group of stakeholders in the area who have adopted a new circular economy operating model which is wanted to be copied elsewhere in Finland. The results of the work will be shared with stakeholders in seminars, and those working in the field will be informed in workshops to deeply understand the need and significance of the change. Emission measurements will be made of the utilized demolition fractions, for example, for heavy metals and PAH compounds. The review of operational methods examines the stakeholders, operational processes, value networks and opportunities for their development in demolition projects. In particular, demolition projects are discussed from the perspective of the circular economy and life cycle assessment theory. Special attention is paid to the harmful substances in demolition sites and demolition materials and the safety and health of their recycling or reuse. Demolition materials are a mixture of recoverable materials, currently unrecoverable materials and various impurities, some of which are harmful to the environment and health or even dangerous. In demolition pilots, harmful and dangerous substances, such as asbestos, are identified in advance, separated or treated, and it is ensured that the demolition materials to be utilized do not contain harmful amounts of impurities. One of the goals of the project is to enable future use of currently unusable materials through research and to reduce the need for landfilling. Already during the project, efforts are being made to use demolition aggregates in road and bridge construction and in industry.

Materials

Report (in Finnish): Selvitys viranomaisohjauksesta ja lainsäädännöstä purkuhankkeissa

Report (in Finnish): Raportti toimialan muutostarpeista