Town Planning Review

Climate-resilience-oriented transformations of housing policy: strategic impulses from a multi-level real-world lab in the Ruhr

Town Planning Review (2022), 93, (2), 211–233.

Abstract

In response to the climate emergency declared in many German cities in 2019, political decision makers, planners and researchers began promoting climate resilience in policy areas such as housing. This article discusses the potential impact and implementation of housing-market monitoring and housing action plans on analytical and strategic capacities at local and regional levels by presenting findings from a transdisciplinary, multi-level real-world laboratory in the Ruhr city region in Germany. It proposes an integrated multi-level approach to raise awareness and provide an accessible database for housing policies in climate-resilient city regions across administrative levels and sectoral borders.

Published open access under a CC BY licence. https://creativecommons.org/licences/by/4.0/

Climate-resilience-oriented transformations of housing policy: strategic impulses from a multi-level real-world lab in the Ruhr

Abstract

In response to the climate emergency declared in many German cities in 2019, political decision makers, planners and researchers began promoting climate resilience in policy areas such as housing. This article discusses the potential impact and implementation of housing-market monitoring and housing action plans on analytical and strategic capacities at local and regional levels by presenting findings from a transdisciplinary, multi-level real-world laboratory in the Ruhr city region in Germany. It proposes an integrated multi-level approach to raise awareness and provide an accessible database for housing policies in climate-resilient city regions across administrative levels and sectoral borders.

Published open access under a CC BY licence. https://creativecommons.org/licences/by/4.0/

Introduction: transforming the housing sector for climate resilience

In 2019, municipalities in Germany and many other countries declared a state of climate emergency. Political decision makers and researchers began to look for strategies to mainstream climate resilience in policy areas that had formerly been more or less unaffected by debates about climate change. One of these policy areas is housing. The housing sector, and housing policy, play a key role in reaching global, national and local sustainability and resilience goals, such as Sustainable Development Goal 11: make cities and human settlements inclusive, safe, resilient and sustainable (United Nations, 2015).

Current academic debates distinguish between climate-resilient housing and housing for climate-resilient cities (see Vale et al., 2014). Climate-resilient housing policies focus on structural stability and adaptations in technical terms to provide residents with better (physical) protection, but neglect adaptability to changing climatic and environmental conditions. This approach is far from meeting the wider holistic housing agenda for climate-resilient cities that includes various dimensions of resilience. Housing for climate-resilient cities addresses the living environment more comprehensively, including social networks and participation as well as other social, economic and environmental factors (Ahmed and Charlesworth, 2015; Vale et al., 2014). This holistic housing agenda calls for a demand-oriented, affordable, preventive and adaptable housing supply that contributes to mitigating both greenhouse gas emissions and local impacts of climate change, while strengthening social cohesion and environmental justice. So far, the international debate on climate resilience in the housing sector has mostly focused on social housing (e.g. Gibb et al., 2016; Mavrogianni et al., 2015) and on housing conditions in megacities and the global South, where vulnerability is particularly high (e.g. Lau and Murie, 2017; Nurdini et al., 2017; Kijewski-Correa and Taflanidis, 2012). In this article, we present an integrated approach to combining housing and climate resilience in a polycentric metropolitan city region in Europe, based on a multi-level case study in the Ruhr, Germany.

German city regions currently face manifold housing challenges, and issues of climate resilience and environmental justice make housing an even more complex matter. Housing development has diversified over the past decades in many German regions. While the demand for single-family homes in suburban environments continues to be high, an increasing number of single-person households - among them many seniors - prefer housing in suburban and urban centres close to local amenities and public transport, but also urban green spaces. For affluent population groups, housing is an important dimension of consumption and means of self-fulfilment (Koch, 2020, 172 ff.). The quality of living environments is a decisive factor in their choice of housing. Location and environmental quality are important drivers for housing prices both in owner-occupied and in rental housing-market segments, which bear the risk of exacerbating residential segregation. As a result, vulnerable residential groups tend to live in neighbourhoods with less access to green spaces and higher pollution (see Ohlmeyer et al. in this issue; Greiving and Fleischhauer in this issue). Nonetheless, housing as a social good competes with housing as a commodity. The ever-increasing demand for (inner-city) urban housing collides with political targets such as the reduction of land consumption. One example is the German national target of a maximum additional land consumption of 30 hectares per day until 2020, which has not been reached. For decision makers, it often seems that they must choose between new housing construction and environmental-protection goals, and that these targets cannot be reconciled. Up until now, there has been no consensus among housing and climate experts about common goals, reliable structures and strategies. Sectoral thinking determines both policy areas, and underlines the need for a common information base for decision making.

Due to the increasing impact of climate change and diversified housing demands at the local scale, many municipalities have recognised the need to take a more proactive role in housing policy. Paradigms have shifted from promoting social-housing supply through tax incentives and supporting low-income households through rent subsidies (Heeler, 1994) to a broader use of holistic and adaptable strategies and plans (Borchard, 2011). Municipal decision makers have also started to pay more attention to the regional level, as households who cannot fulfil their housing aspirations in one municipality might just move on to the next. Competition for residents - and for the tax revenues they bring with them - leads to the neglect of shared regional interests or political objectives such as the preservation of green open spaces (which fulfil important functions in climate adaptation). Divergent municipal interests complicate collaboration to integrate housing and climate-resilience challenges at the regional level. Currently, scholarly researchers - not only in Germany but also in other European countries - are analysing the role that the regional level may play in both the provision of affordable housing and capacity building for resilience (Zimmermann, 2020).

This article discusses housing-market monitoring systems (HMMSs) and housing action plans (HAPs) as potential mechanisms and instruments for municipal and regional decision makers to provide demand-oriented and affordable housing. In addition, the article considers housing quality and targets for climate-resilient cities from a multi-level governance perspective. We present findings from a three-year transdisciplinary research project, funded by the German Federal Ministry of Education and Research (BMBF). For this article, we focus on the content, creation and implementation of HMMSs and HAPs against the background of local and regional governance systems related to climate resilience and housing policies. This integrative perspective helps to deal with conflicting objectives (e.g. between energy retrofitting, affordability and accessibility) and to exploit potential synergies at an early stage. The research followed a multi-level real-world laboratory (RwL) approach at district, municipal and regional levels with administrative project partners on each level (see Sieber et al. in this issue).

In the following section, we further elaborate on our methods and database. Afterwards, we present our empirical findings about the integration of climate resilience into housing-market monitoring systems and housing action plans at the municipal and regional levels. Then, we discuss the strategic challenges of integrating climate resilience into the multi-level governance of housing in the Ruhr and in more general terms. In the following section, we provide options for climate-resilient housing policies by enhancing the discussed governance mechanisms and their governance prerequisites. Finally, we reflect on how the two housing policy instruments can initiate transformation in the short and longer term, and which opportunities RwLs offer in this regard.

Case study, methods, database

Transdisciplinary research is an important framework for research that aims to generate solid knowledge and solutions which address real-world environmental and social challenges. In our research, we used the RwL framework (see e.g. Schäpke et al., 2018; Wanner et al., 2018), characterised by a transformative approach (real-world) experiments, transdisciplinarity, long-term orientation and transferability, as well as reflexive learning. The transdisciplinary co-research team consisted of university researchers and representatives of municipal and regional administrations. It employed a variety of methods ranging from traditional techniques of empirical social research (interviews, participant observation) to transdisciplinary forms of elicitation, validation and elaboration.

Our case study is located in the polycentric Ruhr region. With about 5.1 million inhabitants and an area of almost 4,440 square kilometres, the Ruhr is the largest German urban agglomeration and one of the largest in Europe. The self-governed regional association includes eleven urban municipalities and four counties. The city region is characterised by a significant urban-rural gap (see Figure 1), with highly compact and sprawling settlement areas lying side by side, regardless of municipal boundaries. The region’s industrial heritage still characterises its social structure, even though it has become much more socially heterogeneous in the course of structural change. Not all social groups have benefited from this change: on average, the Ruhr is one of the economically weakest regions in Germany, in terms of both municipal and private households. Only ten of 53 cities expect population growth, while the remaining 43 are expected to stagnate or even shrink (Iwer and Alfken, 2018). But there is small-scale differentiated growth and shrinkage within all municipalities. The polycentric and financial situation of the municipalities intensifies their competitive behaviour for residents, especially high-income ones. The regional institutional body Regionalverband Ruhr (RVR, Ruhr Regional Association) has no formal competence for housing but has nonetheless set up a working group of municipal-housing experts from the urban municipalities and counties to enhance mutual learning, intercommunal exchange and the development and coordination of new regional housing instruments such as a regional HMMS.

Population density in the Ruhr

Source: Authors’ own figure based on Iwer and Alfken (2018, 29); database: IT.NRW

The study focussed on housing-market monitoring systems (HMMSs) and housing action plans (HAPs) at the municipal and regional levels as instruments to link housing objectives with urban development, climate and environmental policy (MBWSV NRW, 2016). We conducted a comprehensive document analysis of municipal housing-market reports (n = 9) and municipal HAPs (n = 28) in the Ruhr. Similarly, we examined the regional housing-market reports of the Ruhr (n = 4) and all regional HAPs existing nationwide (n = 5) for best-practice examples. To validate the results, we carried out two transdisciplinary workshops, which also became an important knowledge base for the following initiative and for the development of an integrated regional HAP in a series of transdisciplinary workshops. An evaluation of the implementation process will be the next step.

Climate resilience in municipal and regional HMMSs and HAPs: empirical findings in the Ruhr

Cities in the Ruhr face several challenges that are not easily reconciled, such as the creation of a demand-driven housing supply and the provision of affordable, yet high-quality, housing. The operationalisation of these targets is controversial and depends on the operationalisation of the resilience concept. Therefore it is ultimately a matter for negotiation at the particular local and regional levels. Demand-orientation, for example, empirically often refers to actual and projected household types in connection with preferred locations and housing quality. Those households which depend upon certain housing requirements (e.g. accessibility) deserve more attention. To measure affordability, housing-market observers often use the share of the available net household income as a guide. In this section, we present instruments that might potentially support the negotiation of these issues and thus the development of a climate-resilient city region.

In our initial analysis, we identified key tasks for the integration of climate-resilience issues into housing policies: raising awareness among politicians and housing experts in public administrations, extending an accessible database for public and private decision making, and developing common guidelines and objectives across administrative levels and borders. HMMSs and HAPs are instruments that potentially allow the integration of climate and environmental issues. An HMMS aims at the systematic, differentiated and contemporary analysis of the municipal housing market (Forum KomWoB, 2020; Rohr-Zänker, 2002). Based on this monitoring, a HAP presents strategies for active housing policies and allows the linking of housing issues with urban and regional development goals, from overall objectives to concrete implementation measures.

Housing market monitoring systems (HMMSs)

Only nine out of 53 cities in the Ruhr produce a public municipal housing-market report, and only three of them conduct continuous monitoring with at least three consecutive reporting intervals (see Figure 2, as of December 2019). This is the result of housing-market monitoring being a voluntary municipal task, which is always in danger of falling victim to austerity measures in the notoriously insolvent Ruhr municipalities.

Housing-market monitoring reports in the Ruhr

As municipal HMMSs are not standardised planning instruments, there are great differences in content and quality, ranging from no systematic monitoring at all to high-quality surveys and comprehensive evaluations at the borough or district level. The reports differ greatly regarding indicators and levels of detail. Although there is a non-binding set of indicators proposed by a national association for the establishment and development of municipal HMMSs (Forum KomWoB in German), the final design depends on the interests of the particular municipality and ends at its administrative boundaries. Nevertheless, most reports consider the topics and (proxy) indicators shown in Table 1. The statistical or qualitative data in the reports are not differentiated on a small scale or linked to geodata, which reduces the informative value of the monitoring.

Topics and examples of frequently used (proxy) indicators in the municipal housing market reports

Topic Subtopic Criteria of differentiation Examples of frequently used (proxy) indicators
Real-estate and property market / Sub-markets and/or segments Land values, (average) prices for building plots, land prices, number of purchases, etc.
Housing supply New residential constructions Sub-markets Relative construction activity, number of construction completion, number of construction permits, etc.
Housing stock Sub-markets Number of residential buildings and apartments, living space in square metres per person, etc.
Social housing Sub-markets Total amount of grant funding, number of social-housing units, etc.
Housing vacancies Sub-markets Number of vacant apartments according to electricity meters, etc.
Housing demand Development of the population Demographic market segments Natural population development, number of inhabitants, demographic structure, etc.
Development of households Demographic market segments Number of households, number of different household sizes and types/household structure, etc.
Projection of population and households Demographic market segments Population projection, projections of household development
Migration Demographic market segments Moving frequency within the city, urban-rural migration/migration balance, etc.
(Rent) price development / Sub-markets and/or segments Qualified rent index, quoted rents, consumer price indices, etc.

No HMMSs - with one exception, which we describe below - include indicators that in any way address aspects of climate resilience or environmental justice. The stakeholders mostly ascribe the missing integration to

  • a lack of responsibility for and awareness of climate/environmental issues,

  • a lack of personal and financial resources,

  • a lack of available data and

  • an overload caused by too many indicators.

  • Apart from the lack of awareness, integration of climate-related issues into housing monitoring seems to be an organisational problem. Only the City of Duisburg manages to include environmental justice in an excursus. Its representatives stress the importance of good interdepartmental relations between the housing and environmental department and the importance of the availability of competent staff. As a result, the report relates micro-scale data on noise emissions, air pollutants and bioclimatic impact to data on poverty (see Table 2; City of Duisburg, 2018). Duisburg’s excursus on environmental justice underpins the benefits of interdisciplinary cooperation, of not only considering questions of future environmentally friendly and resilient urban development adequately, but also initiating awareness-raising processes among and beyond the processing team.

    Indicators used in the excurses on environmental justice in the housing-market report of Duisburg

    Topic Indicator(s) used in the excurses Classification
    Noise pollution Share of settlement area per residential district with noise levels above 55 dB(A) at night and 65 dB(A) during the day Classification into the characteristics ‘low’, ‘medium’ or ‘high’ according to the affected settlement area per residential district
    Air pollution: nitrogen dioxide pollution Share of settlement area per residential district where the threshold for nitrogen dioxide (40 µg/m3) is exceeded Classification into the characteristics ‘low’, ‘medium’ or ‘high’ according to the affected settlement area per residential district
    Bioclimatic conditions/heat stress Share of settlement area per residential district with negative bioclimate for human health Classification into the characteristics ‘low’, ‘medium’ or ‘high’ according to the affected settlement area per residential district
    Poverty Share of households in a residential district receiving either minimum benefits or housing benefits Classification into the characteristics ‘low’, ‘medium’ or ‘high’ according to the percentage of households (reference: entire city) per residential district

    Source: Authors’ own table based on City of Duisburg (2018)

    In contrast to the more or less fragmentary reports at the municipal level, the Ruhr has a rather long-standing tradition of regional housing-market monitoring. Since the first regional report in 2009, the responsible working group published further reports every three years. The catalogue of indicators comprises information about housing supply and demand and the land and property market at the large-scale city level (Städteregion Ruhr, 2009). However, up to now, the regional reports have not considered aspects of climate resilience and environmental justice. Similar to the municipal level, the actors involved identify a lack of resources as a great challenge. In addition, the problems lie in the data availability and comparability at the regional level as well as in the different frameworks and responsibilities of member counties and urban municipalities.

    However, it is possible to combine existing housing-related and climate-related data based on the already existing geo-monitoring systems ruhrFIS (land and demographic data information system), KlimaFIS (geodata-based information system on climatic conditions), and the regional solar and green-roof register, which we will further elaborate on below. ruhrFIS combines (1) monitoring of settlement areas (with reference to municipal and regional land-use plans) with (2) reserve areas for housing and determination of future requirements, and (3) data on public services and social infrastructure (RVR, 2020). The RVR regional association and its member municipalities have not yet fully exploited the potential of ruhrFIS either in content or in organisation. Additionally, municipal competition in the polycentric city region plays an important role: some municipalities do not want to share their small-scale municipal data with neighbouring municipalities. As a result, only the RVR as the organiser of the database has full access to the available regional data on ruhrFIS, while the municipalities have access only to their own city area. For a city region to become climate-resilient, regional data need to be accessible to all.

    In summary, although a municipal HMMS offers many flexible possibilities of linking housing and climate resilience, integration has so far struggled either with a lack of awareness and/or competencies or with structural problems caused by data management and resource availability in financially weak municipalities. The same applies to regional housing-market monitoring: comprehensive regional information, which addresses the challenges of a housing policy by meeting the needs of a climate-resilient city region, does not exist. The city region and its municipalities and counties need to combine comprehensive and small-scale data with a regional geo-information system to intersect data layers. As Gibb et al. (2012) point out for the case of Belfast, housing markets in many polycentric regions depend less on administrative than on functional market boundaries (due to high levels of commuting and multi-local homes). This is also true for the Ruhr. Therefore regional monitoring has to take functional interrelations into account.

    Housing action plans (HAPs)

    Monitoring alone is not sufficient to ensure that decision makers and planners are able to consider climate resilience in current and future housing policies. It must rather be a part of city- and region-wide strategies for housing, such as dedicated action plans. Similar to HMMSs, a housing action plan is an informal, flexible and non-standardised instrument. Currently, 31 out of 53 cities in the Ruhr have an action plan in place or in process (see Figure 3, as of December 2019). The processing of a regional HAP has just started. Again, there are large qualitative and quantitative differences in thematic depth (i.e. objectives, strategies, measures and instruments) in the existing municipal action plans. While some cities define concrete measures, such as building a certain number of new homes in a specific area, other HAPs only include general objectives without giving further information on how to reach them.

    Housing action plans in the Ruhr

    Municipal HAPs have become popular only recently; more than half of them are no older than five years. This is due to a more proactive attitude to housing policy, caused by increasing pressure on the housing market, the increasing demand for single homes mentioned above, and the temporary population growth following high numbers of incoming refugees in 2015. However, municipal HAPs also fulfil another very specific purpose, as they are a prerequisite for applying for subsidies. Most HAPs contain components of housing, such as land and housing development, revitalisation of housing stock, housing for specific target groups such as students and the elderly, and neighbourhood development. These components show the differentiated market situations in the polycentric city region. Some HAPs focus on the refurbishment of housing stock, others directly on land development. Even in shrinking areas, the creation of new high-quality housing is important for the municipalities to attract residents, regardless of available living space in neighbouring municipalities. Municipalities with a high demand for housing are in a position to define and implement high-quality standards. Overall, however, municipal HAPs barely take account of climate resilience.

    Environmental requirements in the housing sector have a lower priority than more urgent problems, from a political and administrative perspective. The authorities have not yet recognised the importance of climate resilience in the field of housing policy. Adaptation to climate change is a primary objective in only one municipal HAP in the Ruhr. In general, only other primary objectives, legal requirements and public support indirectly reflect objectives and measures to increase climate resilience. These are, for example:

  • modernisation of energy systems in the housing stock (a legal requirement especially for social housing, including specific funding structures),

  • small-sized area mobilisation (infill building),

  • demolition and reconstruction of buildings in underused areas and

  • land recycling of brownfields and vacant plots (to fulfil the goal of thirty hectares per day noted above).

  • All these aspects relate to a rather technical definition of climate-resilient housing as introduced above. To reach the more comprehensive goal of housing for climate-resilient cities, the municipal HAPs need broader perspectives. For example, the designation of former greenfield sites as building land often contradicts the ideal of climate-resilient land development as it neglects the need for space for precipitation, cold- and fresh-air production, community building, etc. In general, the only relevant topics addressed in HAPs are deconstruction and energy retrofitting, but rarely climate-resilience criteria for new residential construction. Even climate-mitigation requirements for new residential construction appear to depend primarily on political regulation at the national level (e.g. efficiency standards), but do not go beyond these legally prescribed requirements, which are sometimes considered too strict. Some local authorities see energy-efficiency improvements as an opportunity to minimise additional housing costs for residents (for heating and warm water) in the long term, while others argue that they will lead to rising rental costs (Grossmann, 2019).

    Interestingly, many municipalities commission the same private consultancies to create their HAP. As a result, many HAPs contain best practices from some cities in similar ways, such as a ‘climate bonus’ for rents paid by municipalities for recipients of social welfare. With a climate bonus, the municipality allows tenants who depend on welfare to exceed the permitted maximum amount for the base rent, if the owner has modernised the dwelling in accordance with a defined energy standard. This is intended to create modernisation incentives for the owners while keeping heating costs for the tenants at a low level. However, municipal HAPs very rarely take up new perspectives, inspirations, or even innovations. To promote follow-up contracts, private consultancies strive to develop HAPs that will, in the end, be ratified politically. Thus the current reluctance of politicians towards quantifiable goals or other liabilities influences the work of administrations and private consultancies. The need for political ratification of HAPs seems to be one of the main obstacles in the integration of climate resilience into these plans. At the same time, it is also a future opportunity to give more political weight to climate-related objectives and measures for housing, not least due to the climate emergency.

    At the regional level, the Ruhr offers good prerequisites for the development of joint strategic action plans. In 2019, the RVR regional assembly - in contrast to most other German city regions, the Ruhr has a democratically legitimate decision-making body - declared a climate offensive (similar to a climate emergency). Thus the region aims to foster regional strategies for climate mitigation and adaptation in the near future, and decision makers are currently discussing a regional HAP for the Ruhr. The political mandate to develop a consensual regional housing concept opens up the opportunity not only to fulfil an obligatory task, but also to act with foresight and to directly take up further policy objectives to create a housing market for a climate-resilient city region and to supplement the municipal concepts.

    In addition to the housing-market monitoring reports described above, the municipal housing experts working group published a strategy paper with recommendations for regional action and starting points for joint further development of housing policy and planning instruments (AG Wohnungsmarkt Ruhr, 2014). Together with a private consultancy, they conducted an analysis of regional housing demand in the Ruhr up to 2040. This analysis supplements existing monitoring with the important element of the future development of the quantitative and qualitative demand for housing (Abraham et al., 2018). With this analysis, the basis for a regional housing-market strategy is already in place, even though the analysis does not yet address the issue of climate resilience. Obstacles to the realisation of a common strategy are the heterogeneity of local housing markets, small-scale differentiated population development and the availability of building land in municipalities with tight housing markets. Besides, all municipalities in the region compete for upper- and middle-class residents by providing more and more building plots, which makes it more complicated to put this strategy into practice.

    Strategic challenges for the integration of climate resilience into housing in the Ruhr

    HMMSs and HAPs are becoming an increasingly important basis for municipal housing policies, although municipalities have not yet fully exploited the potential for linking them to climate-resilience objectives. In particular, monitoring systems are under increasing pressure due to a lack of staff and financial resources. As a result, some cities have reorganised their former public housing market reporting so that it has become purely internal monitoring within the administration. This is more resource-efficient, even if reporting is then only available to a smaller audience and does not serve as an adequate means of communication and awareness raising. Resource availability also plays a role when the HMMS experts in the Ruhr discuss a possible overload or loss of the instrument’s actual focus through the additional consideration of climate resilience. However, integrated monitoring enhances efficient resource management since it provides decision makers with essential information (Forum KomWoB, 2020; Rohr-Zänker, 2002). This is particularly important as decision makers always feel the need to choose between housing and environmental objectives. Linked to climate and environmental data, (municipal) housing-market monitoring makes problem areas visible at an early stage, e.g. defined by high shares of vulnerable populations, high environmental pollution, high vulnerability to climate-induced events, etc. Such a visualisation reveals the responsibilities of the actors in housing policy.

    The impacts of climate and environmental changes, as well as challenges for housing markets, do not end at administrative borders. Housing markets in metropolitan areas have always been regionalised due to high mobility and regional economic linkages. Municipal information is therefore insufficient to explain municipal housing market processes; rather, a regional dimension of housing-market monitoring is important. This is especially true for the Ruhr, since in this densely populated polycentric region changes in one municipality directly affect neighbouring municipalities and municipal borders sometimes run directly through residential areas. This also applies to the field of climate resilience as climate impacts such as heat, flooding or water scarcity are of a cross-border nature and therefore require intensive communication and coordination and large-scale solutions. Competitive behaviour and parochial thinking hinder an integrated regional view based on a common regional small-scale database. Monitoring the housing market with regard to the climate and the environment only makes sense if it is implemented throughout an entire region.

    The empirical findings above also show that information systems, stakeholder networks, reports and estimates of future developments, which are assets when it comes to the development of regional monitoring systems and housing strategies, do exist at the regional level. A regional HAP can strengthen the city region’s competitive position, the provision of a diverse housing supply for different target groups and housing needs, specific regional qualities, and identity. However, the political coordination of collaborative approaches - both in monitoring and in collaborative action - seems to be difficult. A polycentric region such as the Ruhr is heterogeneous in many ways and particularly with regard to its housing markets. Politicians need to consider a variety of - partly contradictory - interests, for example in low- and high-density areas, growing and shrinking areas, or rural and urban structures, as well in areas with higher or lower flooding risk, heat stress or pollution. Moreover, at the regional level, specific features of governance meet. The RVR itself has no direct authority. Since housing policy is a municipal task, the involvement of, and consensus building among, municipal decision makers is essential in considering the various municipal needs of member cities. However, the Ruhr benefits from a special feature: the RVR regional assembly. This is an essential prerequisite for binding action. Regional housing strategies are a new policy area; so far, there are only a few in Germany, e.g. in Hanover and Bremen, which as monocentric regions are not easily comparable to the Ruhr. However, the housing experts of the city region can take ideas from these processes and strategies into consideration and, where appropriate, adapt them to the specific situation of the Ruhr. Climate change does not stop at municipal boundaries; therefore pursuing housing for climate-resilient city regions is a perfect regional complement to existing municipal strategies. Even if it requires some effort, a consistent regional funding framework and a regional consensus on the supply of affordable housing are helpful in implementing a regional HAP. Further challenges for housing markets, such as increasing social polarisation and its links to environmental pressures, must be taken into account.

    Housing policies for climate-resilient city regions: options for a strategic multi-level approach

    In the previous section, we used the findings of our case study to illustrate the particular framework in the Ruhr and, at the same time, to show the broader challenges of integrating climate-resilience objectives into housing policies. These challenges will be found in many - not only polycentric - regions. In this section, we present the options for a multi-level approach to developing housing policies for climate-resilient city regions. We argue that there is an urgent need for integrating or even mainstreaming climate resilience in other policy areas, since ‘[t]he decisions we make today about how we build and live in cities will affect generations to come’ (Wigginton et al., 2016, 905). Taking into account resilience, quality of life and energy efficiency are essential dimensions of urban transformation (Kabisch et al., 2018).

    Housing and climate challenges are pressing issues, which require a joint discussion involving local and regional housing and climate experts. Striving for climate-resilient cities calls for a further paradigm shift in housing policy towards a transdisciplinary approach to social and environmental issues. Because of the polycentricity of the Ruhr, different initial situations and competing interests collide, even though many local experts recognise the need for collective climate-resilience strategies in the housing sector. To raise awareness of climate issues among housing experts and of housing issues among climate experts,

  • HMMSs need to provide a continuous, comprehensive, cross-border accessible database for decision makers, and

  • HAPs need to be based on integrated and common guidelines and objectives across administrative levels and borders.

  • In particular, the repertoire of informal housing policy tools has great potential to facilitate a transdisciplinary link with climate and environmental issues. Although the member municipalities of the city region have increasingly used such instruments - especially HAPs - in recent years, these instruments still have a strong sectoral focus, which must be expanded to develop a climate-resilient city region.

    Comprehensive regional and municipal housing-market monitoring systems

    Since climate and housing issues do not end at municipal borders, housing monitoring also has to cross administrative boundaries. To extend HMMSs with data on climate resilience, environmental justice and development indicators, the city region and its member municipalities must take account of theoretical, methodological, practical and political requirements (UNDP, 1997; 2002). By doing so, the indicators must meet certain criteria, including quality of operationalisation, measurement, implementation/feasibility and political recognition. Following these criteria and based on a municipal investigation of environmental justice (see Ohlmeyer et al. in this issue), we developed a set of indicators (see Table 3). To address the concerns of housing experts about overloading and the loss of the HMMSs’ actual focus, housing-market observers should successively add only climate-resilience-related information that is particularly relevant to housing, starting with data that are already available and regularly updated. Simultaneously, they can gradually build up further relevant data sets.

    Set of information for considering environmental and climate issues in housing-market monitoring

    Building-related criteria/information
    Criterion Indicator(s) Data source
    Potentials of photovoltaic systems Localisation of suitable roof surface for photovoltaic systems/solar thermal plants, level of solar potential for photovoltaic systems/solar thermal plants, average strength of irradiation Solardachkataster (solar register), available at regional level, provided by the RVR regional association
    Potentials of roof greening Localisation of suitable roof area and level of potential for green roofs Gründachkataster (green-roof register), available at regional level, provided by the RVR regional association
    Energy efficiency Energy-efficiency classifications (energy demand/consumption), etc. /
    Building insulation Quality of building insulation, availability of facade greening, etc. /
    Building technology Quality of heating system, technology, degree of networking of technical devices (smarthome), etc. /
    Damage potential Damage potential (in euros) due to winter storms, hail, heat, heavy rainfall, forest fire, lightning, and snow load GIS ImmoRisk Naturgefahren, available at national level, provided by the Federal Institute for Research on Building, Urban Affairs and Spatial Development
    Spatial criteria / information
    Criterion Indicator(s) Data source
    Land-use restrictions in favour of environmental and climatic functions Localisation of flood areas, cold-air-producing areas, areas transporting cold air, etc. KlimaFIS & Regionalplan (regional land-use plan), available at regional level, provided by the RVR regional association
    Allocation of urban green areas Localisation of urban green areas German Digital Landscape Model (ATKIS Base-DLM), available at national level, provided by ATKIS®
    Accessibility of urban green areas Localisation of a supply area (500 m distance measured around the access points to the urban green area) /
    Air pollution Average level of air-pollutant concentration (e.g., particulate matter, nitrogen oxide, etc.) Emissionskataster Luft NRW (emissions register for air pollutants), available at state level, provided by the state of NRW
    Noise pollution Average level of noise pollution of different sources (i.e. road traffic, rail traffic, air traffic, ship traffic, etc.) Strategische Lärmkarten (strategic noise maps), available at state level, provided by the state of NRW and the German Federal Office for Railways
    Bioclimatic conditions/heat stress Local climate zones, number of hot days (≥ 30 °C), number of tropical nights (≥ 20 °C), Physiological equivalent temperature (PET), etc. KlimaFIS and Klimatoptypenkartierung (map of local climate zones), available at regional level, provided by the RVR regional association
    Flood risk Residential buildings within inundation areas in case of a 100-yearly flood Hochwassergefahrenkarten (flood hazard maps), available at state level, provided by the state of NRW
    Radiation Average intensity of ultraviolet radiation, localisation and average intensity of mobile phone antennas, etc. /
    Light pollution Localisation and average intensity of illuminated advertising, floodlights, etc. /

    For the Ruhr, most necessary climate- and environment-related spatial data and instruments for systematic housing monitoring are available and housing market observers only need to link with each other and monitor on a small scale. This implies that municipalities share their micro-scale land-use data. Merged micro-scale monitoring provided by the RVR would allow more detailed, continuous monitoring compared to the current regional monitoring. By using an online tool, the possibility of deactivating particular layers counteracts the fear of overload. In conclusion, the primary challenge is not the implementation of data linkage, but rather awareness and governance frameworks.

    Holistic and integrated municipal and regional housing action plans

    So far, municipal action plans for housing in the region have only defined some objectives and measures for climate mitigation. This goes along with the required paradigm shift to connect housing and climate resilience to each other and to the regional perspective of the housing market. At the regional level, housing experts can ideally address integration in the context of regionally coordinated land and housing-stock development. This means:

  • the coordination of real-estate, land development and land-use policies;

  • the reduction of land consumption;

  • land-use restrictions in favour of climate-ecological functions;

  • compensation mechanisms for municipalities affected by restrictions in building-site development;

  • regional standards for housing quality (e.g. accessibility, affordability, climate resilience) which must be applied by investors in all municipalities;

  • the support of networks for innovative forms of co-housing with socio-environmental standards, also as regional pilot projects; and

  • regional funding instruments and networks to activate property owners.

  • By interlinking the municipal and regional levels - not only with climate resilience - the Ruhr can take a pioneering role in German housing policy and provide the region with a new image as a climate-resilient city region.

    Making climate resilience a quality standard for the development of the housing supply means including both climate adaption and mitigation in the planning, design and construction of housing and housing environments. This means more than energetic modernisation. Rather, energy-plus buildings with forms of energy generation (photovoltaics, bio-reactive facades, etc.), sustainable materials and roof or facade greening are mandatory in housing stock and new construction. According to the housing concept for climate-resilient cities from Vale et al. (2014), land development and consideration of the physical structures of buildings are not sufficient without considering the living environment with its ecological and social dimensions. A climate-resilient housing environment minimises risks of climate-related and environmental hazards (e.g. heat islands, noise and air pollution, etc.) and their impacts. It also guarantees fresh-air corridors and the accessibility of green areas, for example for recreation. Innovative housing concepts - such as co-housing - can open up opportunities for environmentally sound and socially resilient neighbourhoods.

    For many housing actors, designating new building plots is the key task in providing affordable, demand-driven housing. The rising demand for housing - especially for single homes - seems to underpin the need for new construction, which opposes the objective of reducing land consumption. Therefore municipal and regional decision makers need to define mandatory climate-resilience standards for land development in multi-level governance settings. For new constructions, policy makers must establish regional climate-resilience standards that address both construction and the living environment. These standards will reduce competition among local authorities if everyone is obliged to follow them. Once municipal competition has been abandoned, municipalities can network to promote climate-resilient urban development through coordinated land and building-plot development, supported by a regional compensation mechanism (i.e. a financial or spatial compensation mechanism). Urban planning competitions and public-private partnerships can then offer the opportunity to ensure climate resilience and socio-ecological quality if the focus goes beyond price and takes developers’ concepts in quality of land use into account.

    Most municipalities see the need for land recycling; however, they must take the needs and interests of property owners into account. A funding programme which provides incentives and a funding network that spreads knowledge about subsidies are good starting points in making climate-resilient refurbishment more attractive to landowners. In addition, they need specific regional funding instruments for region-wide implementation (e.g. regionalisation of funding schemes) and improved interfaces between development banks, approval authorities and investors, e.g. by setting up a regional competence pool for social-housing promotion and climate mitigation and adaption. This would allow planners to support land developers who aim to create climate-resilient neighbourhoods on soil-sealed land, taking into account the (small-scale) differentiation of the regional housing market.

    To provide climate-resilient housing stock, convincing owners to modernise their houses is fundamental. There are sufficient funding opportunities, including funds for climate resilience, but they, and the possibilities of linking them, are often unknown. A regional funding network can bundle human knowledge and financial capacities and even facilitate contact with individual property owners. To supplement the regional network, contact persons are necessary for personal exchange in neighbourhoods that are particularly in need of modernisation, that have high environmental impacts and - in terms of environmental justice - that are socially deprived (for example, high poverty or unemployment rates).

    The renegotiation of the existing strategy paper (see AG Wohnungsmarkt Ruhr, 2014) offers an ideal framework for taking up these substantive priorities and developing an integrated regional HAP. For this purpose, researchers and practitioners must generate more knowledge about the concrete interrelations between housing, climate and environment at meso- and micro levels, and about forecasts of future population and climate developments. However, the climate impact analysis in the Ruhr partly addresses the latter (see Kirstein et al. in this issue) and can serve as a foundation. This analysis reveals possible future climate impacts (e.g. (flash-)flood hazards, etc.) in the present and possible future residential areas of the region.

    Governance frameworks at the municipal and regional levels for integrating climate resilience into housing policy

    The successful integration of climate-resilience issues into housing policy has to meet certain institutional requirements. Governance frameworks can be both the greatest obstacle and the greatest opportunity. The paradigm shift in housing policy must consider an explicit multidisciplinary and multi-level approach since, with their strategic instruments, policy makers negotiate and practitioners deal with issues of housing and climate at different levels.

    In the Ruhr, where budgetary deficits affect many municipalities, the lack of resources (monetary, personnel and time) is a major weakness, while competent and innovative personnel in strategic positions and interfaces is a great asset. Strategic positions include the editors of housing-market reports and action plans, who need to collaborate with environmental and statistics departments and experts and with political decision makers. A thorough collaboration requires opportunities and the willingness for intensive exchange on a horizontal level between different departments and on a vertical level across hierarchies. Exchange networks with other housing-market stakeholders and civil society inside and outside the municipal boundaries encourage ‘thinking outside the box’. This serves as a source of inspiration for new ideas. Overcoming ‘silo thinking’, which is a major obstacle to effective integrated development (Galderisi and Limongi, 2017), is crucial.

    There are also obstacles at the political level. Innovative governance structures (including administrative structures, committees, instruments, etc.) will remain ineffective unless practitioners involve politicians at an early stage. Politicians’ awareness, support and courage adopting an innovative approach are the linchpin in linking housing policy with environmental and climate policy. Since the city council (or the regional assembly) approves housing action plans, it has more influence on HAPs than on housing-market reports, which allows experts inside or outside the administration to be more flexible. Researchers, administrators, housing economists and civil-society actors must emphasise the urgent need for integrated rather than conventional action in transdisciplinary forms of collaboration or exchange.

    At the regional level, municipal administrations must overcome not only silo thinking, but also parochial thinking, among cities. An effective long-term housing policy requires a coherent understanding of the housing system at local and regional levels (Gibb et al., 2012). Municipalities need to recognise and understand the common challenge as an opportunity to reposition the regional housing market. Even if they have different housing needs and preconditions, climate change is a common issue. The region has the chance to take a pioneering role in housing politics in Germany. To this end, it is important to address the heterogeneous initial municipal situations in a common strategy and develop a dynamic approach. At the same time, regionally agreed objectives, standards and compensation mechanisms can reduce competition between cities (e.g. for investors or for residents and their tax revenues).

    Conclusion

    This article has shown that the housing action plan and housing-market monitoring, if implemented consistently, have great potential as instruments for integrating climate resilience into housing policy. In terms of resilience, the combination of informal, more flexible and less standardised instruments, i.e. a housing action plan with regular housing-market monitoring, offers the opportunity to link housing, climate and environmental policies on the one hand and to ensure adaption to uncertain climate and population projections on the other. Conflicting political objectives (e.g. designating new building plots versus preservation of green space) can be identified. Monitoring provides the HAP with a basis for necessary adjustments. The design of planning instruments is important for transformation-oriented resilience. The combination of formal or legally binding and informal instruments ensures that the instruments are both robust and flexible.

    The adaptive planning approach we propose shows similarities to the real-world laboratory approach, as it is based on the four elements of learning, experimentation, dialogue and flexibility. Moreover, this approach places great emphasis on the development of flexible and integrative cooperation between public, private and societal actors and on consensus building. Although informal housing-policy instruments have more flexibility for development, they are also more dependent on political support, and on the awareness and willingness of everyone involved.

    The RwL approach addresses the challenges outlined above by promoting interand transdisciplinary collaboration and initiating transformation processes. An RwL creates the opportunity for unconventional, experimental but crucial cooperation between different disciplines from research and practice, between mutual awareness and understanding. It helps to overcome silo thinking and to bringing together different interests and logics. Our experience shows, however, that it is a time-consuming process: it takes time to establish a common working basis and trust, but also to convince all those involved to cooperate and to highlight the respective benefits. In transdisciplinary working groups, different expectations of success, timelines and motivations meet, and do not always fit together. Although RwL collaborations face specific challenges (see Sieber et al. in this issue), we argue that our case study shows their enormous potential for implementation-oriented transformative research. But drawing up our findings for a broader academic audience - as in this article - has also confronted us with potential dangers of RwL research formats: the transformative knowledge produced is not always equally exploitable in scientific and professional contexts. Finding the necessary balance between seeking pragmatic solutions, as sometimes demanded by practitioners, and scientific rigour, as expected of senior scientists and PhD candidates, is an inevitable and potentially conflictual process, which we nevertheless found worthwhile. However, it challenges the boundaries between different spheres of action and requires openness on all sides. As this type of research is likely to advance in the future to produce transformative knowledge for a wide range of socio-spatial planning problems, we expect this openness to increase, and we look forward to further discussions on the scope of this type of research, its opportunities and its risks.

    References

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    References

    ABRAHAM, T., GRADE, J. and WILBERT, K. (2018), Regionale Nachfrageanalyse Wohnungsmarkt Ruhr 2040 (final report), Bonn, Empirica. Google Scholar

    AG WOHNUNGSMARKT RUHR (eds) (2014), Strategiepapier Perspektive Wohnungsmarkt Ruhr (strategic paper of the Ruhr Housing Market Working Group), Dortmund. Google Scholar

    AHMED, I. and CHARLESWORTH, E. R. (2015), ‘An evaluation framework for assessing resilience of post-disaster housing’, International Journal of Disaster Resilience in the Built Environment, 6, 300-12. Google Scholar

    BORCHARD, S. (2011), Kommunale Wohnungspolitik als Urban Governance: Der Dortmunder Weg - ein Modell mit Transferpotential?, Dortmund, SURF - Stadt- und regionalwissenschaftliches Forschungsnetz Ruhr. Google Scholar

    CITY OF DUISBURG (2018), Wohnbericht 2017: Daten & Analysen zum Duisburger Wohnungsmarkt (municipal housing-market report), Duisburg. Google Scholar

    FORUM KOMWOB (2020), Warum kommunale Wohnungsmarktbeobachtung, https://www.wohnungsmarktbeobachtung.de/kommunen/warum-eine-kommunale-wohnungsmarkt-beobachtung (accessed 30 March 2020). Google Scholar

    GALDERISI, A. and LIMONGI, G. (2017), ‘Beyond a fragmented and sector-oriented knowledge for a sustainable and resilient urban development: the case of the metropolitan city of Naples’, in S. Deppisch (ed.), Urban Regions Now & Tomorrow, Wiesbaden, Springer Fachmedien Wiesbaden, 41-71. Google Scholar

    GIBB, K., McNULTY, D. and McLAUGHLIN, T. (2016), ‘Risk and resilience in the Scottish social housing sector: “We’re all risk managers”’, International Journal of Housing Policy, 16, 435-57. Google Scholar

    GIBB, K., O’SULLIVAN, T. and YOUNG, G. (2012), ‘Analysing the Belfast housing market: learning lessons from extreme volatility’, Town Planning Review, 83, 407-30. Google Scholar

    GROSSMANN, K. (2019), ‘Energy efficiency for whom? A conceptual view on retrofitting, residential segregation and the housing market’, Sociologia urbana e rurale, 119, 78-95. Google Scholar

    HEELER, B. S. (1994), ‘Housing policy and the underclass: the United Kingdom, Germany, and the Netherlands’, Journal of Urban Affairs, 16, 203-20. Google Scholar

    IWER, N. and ALFKEN, C. (eds) (2018), ruhrImpulse: Beiträge zur Regionalentwicklung, Bevölkerung und Wirtschaft, Essen, Regionalverband Ruhr. Google Scholar

    KABISCH, S., KOCH, F., GAWEL, E., HAASE, A., KNAPP, S., KRELLENBERG, K. and ZEHNSDORF, A. (2018), ‘Introduction: urban transformations - sustainable urban development through resource efficiency, quality of life and resilience’, in S. Kabisch, F. Koch, E. Gawel, A. Haase, S. Knapp, K. Krellenberg, J. Nivala and A. Zehnsdorf (eds), Urban Transformations, Cham, Springer International Publishing, xvii-xxviii. Google Scholar

    KIJEWSKI-CORREA, T. and TAFLANIDIS, A. A. (2012), ‘The Haitian housing dilemma: can sustainability and hazard-resilience be achieved?’, Bulletin of Earthquake Engineering, 10, 765-71. Google Scholar

    KOCH, A. (2020), ‘Stadtökologie statt Ökologie: Kommentar zu Lisa Vollmer und Boris Michel “Wohnen in der Klimakrise. Die Wohnungsfrage als ökologische Frage”’, Suburban, 8, 167-76. Google Scholar

    LAU, K. Y. and MURIE, A. (2017), ‘Residualisation and resilience: public housing in Hong Kong’, Housing Studies, 32, 271-95. Google Scholar

    MAVROGIANNI, A., TAYLOR, J., DAVIES, M., THOUA, C. and KOLM-MURRAY, J. (2015), ‘Urban social housing resilience to excess summer heat’, Building Research & Information, 43, 316-33. Google Scholar

    MBWSV NRW (MINISTERIUM FÜR BILDUNG, WOHNEN, STADTENTWICKLUNG UND VERKEHR DES LANDES NORDRHEIN-WESTFALEN) (2016), Leitfaden Handlungskonzepte Wohnen: Vom Beschreiben zum gemeinsamen Handeln, Düsseldorf. Google Scholar

    NURDINI, A., YOVITA, W. and NEGRI, P. (2017), ‘Resiliency and affordability of housing design, Kampong Cieunteung-Bale Endah in Bandung Regency as a case study’, IOP Conference Series: Earth and Environmental Science, 99, 12013, DOI: 10.1088/1755-1315/99/1/012013. Google Scholar

    ROHR-ZÄNKER, R. (2002), ‘Wohnungsmarktbeobachtung als Informations- und Steuerungsinstrument’, Forum Wohnen und Stadtentwicklung, 4, 175-79. Google Scholar

    RVR (REGIONALVERBAND RUHR) (2020), Flächeninformationssystem Ruhr - ruhrFis: Siedlungsbezogenen Raumbeobachtung, https://www.rvr.ruhr/themen/regionalplanung-regionalentwicklung/ruhrfis-flaecheninformationssystem/ (accessed 30 March 2020). Google Scholar

    SCHÄPKE, N., STELZER, F., CANIGLIA, G., BERGMANN, M., WANNER, M., SINGER-BRODOWSKI, M., LOORBACH, D., OLSSON, P., BAEDEKER, C. and LANGET, D. J. (2018), ‘Jointly experimenting for transformation? Shaping real-world laboratories by comparing them’, GAIA: Ecological Perspectives for Science and Society, 27, 85-96. Google Scholar

    STÄDTEREGION RUHR (ed.) (2009), Wohnen in der Städteregion Ruhr (first regional housing-market report), Dortmund. Google Scholar

    UNDP (EVALUATION OFFICE) (ed.) (2002), Guidelines for Outcome Evaluators: Monitoring and Evaluation Companion Series 1, New York, UNDP. Google Scholar

    UNDP (OFFICE OF EVALUATION AND STRATEGIC PLANNING) (ed.) (1997), Results-Oriented Monitoring and Evaluation: A Handbook for Programme Managers, New York, UNDP. Google Scholar

    UNITED NATIONS (2015), Transforming Our World: The 2030 Agenda for Sustainable Development, https://sustainabledevelopment.un.org/content/documents/21252030%20Agenda%20for%20Sustainable%20Development%20web.pdf (accessed 24 April 2020). Google Scholar

    VALE, L. J., SHAMSUDDIN, S., GRAY, A. and BERTUMEN, K. (2014), ‘What affordable housing should afford: housing for resilient cities’, Cityscape: A Journal of Policy Development and Research, 16, 21-50. Google Scholar

    WANNER, M., HILGER, A., WESTERKOWSKI, J., ROSE, M., STELZER, F. and SCHÄPKE, N. (2018), ‘Towards a cyclical concept of real-world laboratories’, disP: The Planning Review, 54, 94-114. Google Scholar

    WIGGINTON, N. S., FAHRENKAMP-UPPENBRINK, J., WIBLE, B. and MALAKOFF, D. (2016), ‘Cities are the future’, Science, 352, 904-5. Google Scholar

    ZIMMERMANN, K. (2020), ‘What is at stake for metropolitan regions and their governance institutions?’, in K. Zimmermann, D. Galland and J. Harrison (eds), Metropolitan Regions, Planning and Governance, Cham, Springer International Publishing, 59-75. Google Scholar