Research Area:
Resource Efficiency of Settlement Structures

Building Land Survey 2020

Nationwide representative sample of building land and infill development potentials

For an informed and future-oriented land management - between the acute call in many places for an increased provision of building land on the one hand and the reduction of new land use as a goal of sustainable development on the other hand - reliable basic data is needed. The main objective of the project is therefore, following on from earlier nationwide surveys, to collect up-to-date data and information on building land reserves and infill development potential as well as on the status and methods of monitoring and mobilizing building land in German cities and municipalities. The project is carried out on behalf of the Federal Ministry of the Interior, Building and Community (BMI) and the Federal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR) in cooperation with the German Economic Institute (IW, Cologne). The survey is supported by the German Association of Cities and Towns and the German Association of Towns and Municipalities.


For some years now, two major topics have been dominating the discussion on land use in the context of settlement development. On the one hand, the limitation of new land use and the protection of the soil are central goals of a sustainable development of the built environment on international and European level as well as in national programs. Thus, responsible use of global land resources is seen as an essential cross-sectional element in achieving the "Sustainable Development Goals". For the European level, the "Environment Action Programme to 2020" refers to the goal of "no net land take by 2050". The German sustainability strategy puts this objective into concrete terms with the aim of limiting the daily new land consumption to less than 30 ha/day by 2030.

On the other hand, in many places - and especially in growing settlement areas - the need for increased and accelerated provision of building land is an issue. Real estate prices and rents continue to rise and affordable housing might become so scarce that not all households will be able to provide themselves with sufficient living space. In order to ensure an adequate supply of housing, the Building Land Commission made suggestions in July 2019, including a recommendation for improved data on building land and greater transparency of building land potentials and requirements.

At the same time, a regular, nationwide comparable survey of core information on land management and building land monitoring is still not carried out in Germany. Independently of surveys at the municipal, regional or state level, the most recent cross-sectional surveys at the federal level are building land surveys from 2003 and 2006 and a survey of infill development potential from 2012. This means that there is a lack of essential up-to-date information for an informed policy towards a future-oriented supply of building land.


Accordingly, the main goal of this project is a nationwide investigation of the building land and infill development potentials by means of a survey of cities and municipalities. Area potentials for residential, commercial and other uses will be surveyed as a basis for nationwide and - as far as possible - regionalized projections as well as projections differentiated by typical spatial categories.

In addition to the quantification of building land and infill development potentials, a further focus of the survey is the mapping of the situation and development tendencies in land data monitoring and land management. This involves both the contents (brownfields, gaps between buildings, vacancies, etc.) and the practices and IT solutions used (land management systems, databases, "tools", etc.).

Finally, a third major concern of the investigations is to collect findings on the accessibility of building land and infill development potentials and mobilization activities, i.e. to estimate the actual accessible availability of potential sites and to identify promising approaches for building land mobilization.

And finally, in addition to national, country-specific and municipal examples, instructive international activities and experiences with the monitoring and mobilization of building land potentials will be researched and evaluated.

Research approach

The basic research approach of the Building Land Survey 2020 is based on 3 methodological approaches:

  • Preparatory research on the methods and status of land monitoring and mobilization

  • Implementation of an online survey among cities and communities

  • Conducting case study investigations

In the course of the preparatory research, existing experiences, approaches, methods and "tools" for land monitoring and mobilization are researched and presented. Initiatives on the different federal levels (federal government, states, regional planning, municipalities) will be considered. This research will be complemented by some interesting international approaches, which can also be transferred to Germany as best practice examples. The analysis also aims to concretize the scope of the investigation with regard to the monitoring of building land potentials, i.e. to determine, for example, which types of land are to be included (definitions).

The core of the project is the preparation, implementation and evaluation of the Building Land Survey 2020 as a standardized online survey. In terms of content, the project will build on core elements of the questionnaire of the Infill Development Survey of 2012 as well as on the questionnaires "Residential Building Land" and "Commercial Building Land" of the Building Land Survey of 2006. Following a suggestion of the German Association of Cities, the survey was in addition merged with a thematically related project of the German Institute of Urban Affairs (Difu, Berlin) on behalf of the Federal Environment Agency on questions of cost-benefit assessment of land development. The sample for the survey comprises about 3,000 cities and municipalities, including all cities and municipalities with 10,000 inhabitants or more as well as a suitable selection of smaller cities and municipalities. The survey will be conducted from July 2020.

In addition to the survey, several systematically selected municipalities of different spatial types and development contexts will be subjected to a more intensive analysis as case studies in cooperation with local practitioners. The central aim of the case studies is to extend and deepen the basic research and to identify innovative and groundbreaking approaches and experiences with the identification and mobilization of building land potentials. In addition, the case study investigations serve to qualitatively substantiate the results of the standardized survey.

Key research questions

The investigations aim to answer the following central research questions:

  • How much building land and infill development potential is available for building use nationwide and in the different regions according to the assessment of the municipalities in Germany?

  • What qualities (location, layout, possible contamination) and what origin (residential / commercial / open spaces / other) do the building land and infill development potentials have?

  • Which future uses are planned, how many residential or commercial units could be realized on the sites?

  • What is the situation regarding land monitoring, land information and land management; what approaches, instruments and development trends exist?

  • What experiences and approaches exist with regard to the accessibility of the land; how is the time frame for mobilization estimated (realized / currently mobilizable / planned)?

  • What national, country-specific and municipal activities and experiences with the identification and mobilization of land potential for building exist beyond the examples collected in the survey and the case studies? Which international examples and experiences offer suitable starting points for a transfer to the situation in Germany?

You can find further Information on the BBSR Project-Homepage (German Language)




Andreas Blum
TPhone +49 351 4679 245



BBSR Project-Homepage (German)


  • German Economic Institut (IW), Köln