BONUS project aims to reduce land consumption
HHow can the increasing land consumption in Austria’s cities be reduced and still create sustainable housing? The RSA FG Research Studio iSPACE provides with the Redensification Monitor a method to identify and monitor housing potentials in cities. In order to mobilize these potentials, the projects BONUS and BONSEI! create a consulting service that promotes socially and environmentally compatible, energy-efficient solutions.
Cities and metropolitan areas are increasingly confronted with decreasing land availability and simultaneous settlement pressure. In addition, cities in particular are facing the challenge of energy-efficient housing refurbishment as an important contribution to climate protection. One approach to finding solutions for more resource-efficient urban regions is to promote internal development and redensification. In Austria, a special role is played by private one- and two-family houses, which account for more than half of the building stock in many cities and have a high potential for densification.
The project BONUS (optimal use of existing buildings – strengthening the environment) under the lead of RSA FG Research Studio iSPACE[i], develops a standardized procedure of a qualitative post-compaction consulting of owners, for the evaluation and mobilization of post-compaction potentials in urban areas. The areas of mobility, open space and greening are explicitly integrated.
Holistic data analysis enables quality consulting
In the predecessor project BONSEI! a broad data basis was started as a basis for a targeted, efficient post-compaction consulting. With the help of innovative GIS methods, potentials for new living space were identified, taking into account density and distance specifications. Other property-related criteria such as location quality, heating requirements and distance to utilities were also integrated and used to prioritize the areas. In the course of BONUS, this database is now being expanded to include mobility and open space criteria.
Based on these calculations, the potential for the city of Salzburg, for example, (assuming 90 m² per residential unit / as of 2019) is 17,249 residential units.
In order to continuously map the progress as well as the further potential of redensification, a semi-automated GIS procedure on the property level was developed with the redensification monitor. The results are incorporated into a holistic, efficient consulting service designed to provide a basis for leveraging energy-efficient, resource-saving and socially acceptable housing potential.
Countering land consumption and climate change
With the implementation of qualitative and data-supported post-densification consulting and subsequent mobilization of housing reserves, cities can create additional living space without expanding or designating building land and thus reduce land consumption. A holistic approach that takes into account various sustainability aspects also contributes to climate protection and quality of life.
BONUS consulting is currently being standardized and implemented in Salzburg and Feldkirch.
[i] Project partners: Energy Institute Vorarlberg, architect Paul Schweizer, City of Salzburg;
LOI partners: Land Salzburg – Dept. 10 Housing and Spatial Planning, Energieberatung Salzburg, Innovations- und Technologietransfer Salzburg GmbH – ITG, Amt der Vorarlberger Landesregierung – Abt. Wohnbauförderung, Amt der Vorarlberger Landesregierung – Abt. VIIa – Raumplanung und Baurecht, Vorarlberger Architektur Institut – vai, Kammer der Architekten und Ingenieurkonsulenten für OÖ und SBG, Stadt Wien – Abteilung Stadtentwicklung und Stadtplanung – MA 18, Verein Bodenfreiheit, Bundesamt für Wohnungswesen (CH), Metron (CH), eza! Energie- und Umweltzentrum Allgäu gemeinnützige GmbH (D)
