Despite continuing disputes and threats of legal action, a temporary capping of housing costs for the existing stock of dwellings was adopted in Berlin in the wake of a successful citizens’ initiative demanding the nationalisation of big private housing companies. Hamburg and other German metropolises try to at least contain rising land prices through the renewal and more decided application of leasehold law and thereby hope to facilitate the implementation of affordable housing projects. Conversely, though, some German tax offices prohibit private landlords or landladies renting out affordable dwellings to write off advertising expenses related to their rental activities unless they charge rents markedly above the local rent indexes, in this way contributing to a further increase of housing costs.

What developments in society have led to this escalation of the housing issue in European metropolises? The answer to this simple question calls for an in-depth engagement with the social, economic, political and cultural development dynamics of our societies - dynamics that are also leaving their mark on urban housing markets. This socio-political mirror reveals the usefulness of an International Building Exhibition on New Social Housing even in a place like Vienna which, due to its municipal housing stock built and maintained over decades, is frequently praised as a social housing paradise by international standards.

Demographic and socio-cultural triggers of the housing question.

For the past 30 years at least, we have known that the populations of many European countries are stagnating or even dwindling as birth rates no longer offset mortality figures despite increasing life expectancy (cf. Berlin Institute for Population and Development 2017). However, national average values deflect attention from the fact that demographic development varies greatly across regions: In most European countries, there are urban growth poles with a sustained national and international influx of young, well-educated individuals hoping to find easier access to future-oriented training and employment opportunities. Thus, the number of Vienna’s inhabitants rose by 217,356 persons in the 2009 - 2019 period (cf. Statistik Austria 2019), while the population increase of Berlin over the same period even exceeded 350,000 persons (cf. Blanken 2019). These growth rates, which equal the population of a major city, are duly reflected in an increased demand for housing, green spaces andinfrastructures. For the past few years, this phenomenon has been the subject of discussion and analysis under the heading of re-urbanisation - an effect that is also noticeable in medium-sized centres and in the environs of compact smaller towns (cf. Scholich 2019; Matthes 2016). Conversely, largely rural areas with poor infrastructures are characterised by declining population figures in many European countries. Enterprises and service providers increasingly complain of labour shortage above all in areas with shrinking populations and hope to balance this lack through population inflow. If younger persons from the same country, other European states or third countries can be attracted to move, the population decline is mitigated by them and their often higher birth rates - but all forecasts indicate that this does not halt the population loss in the long run. Immigration contributes to the rejuvenation and cultural diversity of a population, while demographic ageing continues at the same time. Although the diagnosis that populations in economically stable European countries tend to decline and become both older and more diverse is still true with regard to national averages (cf. Eichner 2003), all studies of demographic change point out that the development of population figures as well as of their age structure and cultural diversity must be evaluated in a spatially differentiated manner to provide a basis for formulating and implementing regionally appropriate action plans for housing, environmental and infrastructure policies. Growth islands with younger and more heterogeneous populations can only emerge where workplaces ensure sufficient incomes, infrastructures meet the demand for childcare, education, healthcare, communication, mobility as well as assistance to the elderly, and tolerance and intercultural understanding support harmonious co-existence despite increasing diversity. Population decline is often accompanied by resentment and political resignation and therefore also calls for measures that contribute to a fundamental vitalisation of affected regions.

On its own, however, population growth cannot safeguard balanced social conditions. Even growth islands have younger and older inhabitants living in precarious income situations. The housing markets of growth regions are affected by housing costs that tend to increase above average especially where private rentals are concerned - a result of the high housing demand triggered by population influx but also because of a rising number of single-person households. At the same time, a privately financed luxury housing segment characterised by above - average land consumption has emerged in many cities, since investors want to benefit from more prosperous client groups able to afford bigger dwellings in attractive locations. Problems relating to the provision of housing exist in all social spaces for home seekers with low incomes or home seekers who due to their origin, number of children or health conditions stand no chance in the competition for the generally insufficient number of affordable dwellings, simply because there are plenty of other interested parties.

Economic and political dimensions of the current urban housing shortage.

In present-day Europe, the shortage of urban housing cannot be solely explained by demographic factors. Even during the recent technological transformation processes, future-oriented employment markets emerged first in urban centres and their peripheries, which traditionally have served as laboratories of social change. Due to sustained economic-political support, they are easy to reach, offer all necessary qualifications and, despite urban stress caused by noise and poor air quality, still boast attractive living conditions for persons who prefer professional success and the manifold advantages of cities to “happiness in the countryside”. Since saving money is no longer worthwhile because of unattractive interest rates, lucrative potentials for investing in commercial real estate and housing projects are likewise clustered in regions of economic and social growth, where companies and service providers required for realestate production and financing are readily available.

Investments in what is called “concrete gold” flourished in the past in all markets characterised by population growth and - if political regulation was lacking - led to above-average increases in prices for rental flats, condominiums and land (cf. Metzger 2018). As before in the 1970s, cities are realising that building land cannot be multiplied and that they need to safeguard and hold stocks of land if they want to be able to influence developments in housing markets and thus their own spatial and social future. All other means to curb housing costs - be it by regulating rents, imposing social rent caps or exercising the right of first refusal in case of property transfers - have proved no more than a drop in the housing shortage ocean amidst a housing market beset by financialisation processes (cf. Heeg 2013; Fields/Uffer 2016).

If then - as happens in Germany - tax offices cause rents to increase beyond the level permitted by the constantly rising local rent indexes [1],, it becomes evident why citizens tend to lose trust in the (by now somewhat optimised) German rent capping, which they find difficult to deal with. Given the rising costs, a freehold flat remains an illusion for all those whose salaries and wages are insufficient to finance a home of their own even with low interest rates in the foreseeable future. Just like all households outside the life phases characterised by paid work, they remain dependent on subsidised housing, whose production has been greatly neglected in Germany since the abolition of limited-profit housing companies. While big cities in particular try to balance this deficit by striving to provide new housing, they continue to meet with fierce opposition on the part of well-organised population groups demanding that the city remain the same - at least in their own residential environment. These groups fear that subsidised housing will entail lower realestate prices, a heterogenised neighbourhood and related confrontations with alien habits and lifestyles resulting from various immigration processes (cf. Arouna et al. 2019).

What can an IBA focusing on New Social Housing do to tackle current social challenges?

It is the central task and an important objective of IBA_Vienna to once more bring social housing issues to the attention of urban policy. Towards this goal, it may draw on the historic achievements of Vienna’s municipal housing programme whose effects help to put a novel spin on neighbourhood co-existence in present-day urban contexts and whose different and innovative new projects widen future perspectives for economic, ecological, political and social action. Yet not only new buildings and the renewal and adaptation of older estates to modern standards play a role here; rather, innovative stakeholder constellations, development and financing models, competition and participation processes, ecological innovations and hybrid forms of use, too, may serve as important assessment criteria for all projects.

Since IBA_Vienna takes place in a metropolis, it is also faced with the challenge of embedding individual projects in their respective urban contexts. This begins with the relationship that any project must have with the surrounding quarter and therefore calls for smart networking - even at the micro level - of all available institutional, economic and social resources; this is the only way to ensure that IBA projects will be able to contribute to the development of both central and peripheral urban quarters that are experienced as liveable by manifold usergroups and thus counteract socio-spatial segregation trends in the city. Such an approach requires the provision of all urban quarters around IBA projects with infrastructures in the form of social, cultural and educational facilities as well as the further development of Vienna’s already exemplary mobility services.

Last but not least, IBA_Vienna can also function as a think tank with its ongoing IBA Talks, international conferences, publications and research projects. Ideally, such formats for dialogue and knowledge transfer can widen the horizon of experts of urban policy and the housing sector and enrich the culture of human interactions in the city with novel knowledge regarding the changing tasks and possibilities of redesigning social housing in connection with other challenges to urban policy, such as climate change, digitalisation, global mobility of goods and people or political polarisation.

References

Arouna, Mariam; Breckner, Ingrid; Ibis, Umut; Schröder, Joachim; Sylla, Cornelia (2019): Fluchtort Stadt. Explorationen in städtische Lebenslagen und Praktiken der Ortsaneignung von Geflüchteten. Wiesbaden: Springer.

Berlin-Institut für Bevölkerung und Entwicklung (2017): Europas demografische Zukunft. Wie sich die Regionen nach einem Jahrzehnt der Krisen entwickeln. https://www.berlin-institut.org/fileadmin/user_upload/Europas_demografische_Zukunft_2017/Europa_online.pdf (Accessed: Oktober 2019)

Blanken, Tobias (2019): Quittung in fünf Jahren. In: DIE ZEIT Nr. 44/2019, 12.

Eichner, Volker (2003): Auswirkungen der demographischen Entwicklung auf die Wohnungsmärkte. In: Wohnungswirtschaft und Mietrecht, Heft 11 (November 2003), 607-612.

Fields, Desiree; Uffer, Sabina (2016): The financialisation of rental housing: A comparative analysis of New York City and Berlin. In: Urban Studies 53/7, 1486-1502.

Heeg, Susanne (2013): Wohnungen als Finanzanlage. In: https://zeitschrift-suburban.de/sys/index.php/suburban/article/view/5/104 (Accessed: Oktober 2019)

Matthes, Gesa (2016): Reurbanisierung und Verkehr. Schriftenreihe des Instituts für Verkehrsplanung und Logistik hrsg. von Heike Fläming und Carsten Gertz. Münster: Münsterscher Verlag für Wissenschaft.

Metzger, Joscha (2018): Betongold: Wohnungen und Immobilien als Kapitalanlage. http://www.bpb.de/politik/innenpolitik/stadt-und-gesellschaft/216876/wohnungen-und-immobilien-als-kapitalanlage (Accessed: Oktober 2019)

Scholich, Dietmar (2019): Reurbanisierung zwischen Wunsch und Wirklichkeit - Ein Blick auf nordwestdeutsche Städte und Regionen. Arbeitsberichte der ARL 27. Hannover: ARL.

Statistik Austria. (2019). Bevölkerung von Wien von 2009 bis 2019. Statista. Statista GmbH. https://de.statista.com/statistik/daten/studie/317867/umfrage/prognose-zur-bevoelkerungsentwicklung-in-wien/ (Accessed: Oktober 2019)

[1] This is a consequence of Germany's federal legislation for the calculation of rent indexes whose only yardstick are new rentals within a certain period, although these are always higher then rent leves for dwellings in existing buildings in the respective area.