Heidelberg wants to become a circular city. In the Patrick Henry Village pilot project, urban mining is to be practiced in existing buildings. The starting point was set with the Urban Mining Screener program developed by EPEA and the Madaster building database.
On the one hand, there is an American housing estate from the 1950s that is ready for demolition and is difficult to convert, and on the other hand, Heidelberg’s ambitious strategy: to become a circular city. So it makes sense to use the huge site of the old barracks to show what is currently possible in terms of the circular economy: to create materials from existing buildings that do not end up in the trash, but are reused on site or recycled in a high-quality way. The principle is called urban mining. Urban prospecting. Use existing houses and roads as raw material storage. It is currently one of the most important concepts in the construction industry for transitioning to a resource turnaround in the long term
More than 300 buildings are to be demolished, renovated or converted and reused in the best possible way in Patrick Henry Village, a district with future apartments for 10,000 people and space for 5,000 jobs. But what exactly can be used for new construction? A question that the so-called digital building material cadastre can answer. The cadastre provides information on which materials, in what quantity and quality can be expected in the event of a building demolition or comprehensive renovation. The two pillars: Urban Mining Screener from EPEA and building database Madaster.
Urban Mining Screener is a program that can estimate their material composition at the touch of a button based on building data such as construction location, year of construction, building volume or building type. EPEA analyzes the existing components and building materials used and maps the data in a Building Circularity Passport, where they are evaluated according to their recyclability. The collected data is then uploaded to the Madaster building database, so that a variety of helpful building data is then available for project development and regional material flow management.
Urban mining in existing buildings and circular construction is not only interesting from a climate point of view. In an economic sense, circular buildings are veritable goldmines for investors. For example, costs for future dismantling, conversion and landfill are saved and the asset value increases by taking into account the residual value of the material, there is potential for value security and long-term value retention through circular building design and future-proof buildings, the image is improved and much more.
A lot has already happened in the former soldiers’ town. The buildings were analysed according to age, size and construction and provided data on the materials used. In this way, options can be shown even before dismantling as to whether and which processing options and recycling routes are available for the individual material flows and what can be needed for new projects, what makes sense for the project, what saves costs, raw materials and CO2.
For Heidelberg, the project represents a further expansion of its pioneering role in the areas of circular construction, the reuse of materials from existing buildings, and the management of building materials and secondary raw materials. Patrick Henry Village (PHP) could become a lighthouse project within the city’s Circular City strategy, lay the foundation for sustainable building material recycling and construction, and be a blueprint for many other projects in other cities.
