Mainstreaming passive houses: more gradual reconfiguration than transition

ABSTRACT

Buildings are major contributors to greenhouse gas emissions and energy consumption. A transition to low-carbon housing requires the introduction of very energy-efficient buildings on a global scale and effective policy measures to support such a transformation. In this article, we study one such radical solution for energy-efficient buildings – the passive house – through a national case study in Sweden. We identify three societal domains where passive houses increasingly become embedded in the building sector: Firstly, the framing of passive houses in the public debate shifted from being presented as a radical alternative for a future low-carbon housing sector to being perceived as a specific low-energy building market segment. Secondly, passive houses have become part of a broader regional institutional and political context rather than a niche. Finally, passive houses have become a driving force for stricter building regulations but in a way that rather led to the assimilation of selected passive house features into existing sectoral structures. We conclude that the dynamics of change we find is rather a ‘mainstreaming’ process of gradual adaptation of construction sector structures and passive houses than a radical transformation of the built environment or the diffusion of new building technology.

KEYWORDS:

• Housing policy
• transition
• mainstreaming
• passive house

1. Introduction

Buildings are major contributors to greenhouse gas emissions (GHG) and energy consumption, both through the energy used to heat and operate buildings and through the ‘grey energy’ embodied in building materials. In Sweden, energy use in buildings is responsible for 40 percent of GHG (SEA, 2020). According to the International Energy Agency (2017), a transition to low-carbon housing would require the introduction of highly energy-efficient building solutions on a global scale. In 2017, the Swedish parliament voted for a national objective of net zero greenhouse gas emissions by 2045 (Government Offices, 2019). Main actors in the Swedish construction sector have proclaimed ‘to take part in this transition and present solutions’ (Fossilfritt Sverige, 2018, p. 3).

One such radical solution on the way to zero-emission buildings is the passive house: a concept that puts particular emphasis on the minimization of heat losses, heat recovery from ventilation, and passive solar gains. The aim is to be ‘truly energy-efficient, comfortable, affordable and ecological at the same time’ (Passipedia, 2019). The concept has strong roots in Sweden and passive houses have been built in Northern Europe since the early 1990s (Müller & Berker, 2013). However, in contrast to the urgency expressed in environmental policy documents, passive houses still have a rather low and uneven uptake in Sweden (LÅGAN, 2020), in comparison with, for example, Germany or Austria where an increasing share of new buildings follow this standard (Ornetzeder & Rohracher, 2009) or Norway where the passive house standard has been made obligatory in the building code for new buildings (Nykamp, 2020). At the European level, the Energy Performance of Buildings Directive (EPBD) sets a target for all new buildings to be nearly zero-energy buildings (nZEB) from 2020. Nevertheless, the requested urgent transition to a highly energy-efficient building stock appears to be much more slow-moving than political targets suggest.

Over the past twenty years, studies on how to understand and manage sustainability transformations in sectors such as energy, transport or housing have become increasingly common, particularly in the field of transition studies (Köhler et al., 2019; Markard et al., 2012). The transition towards low-energy buildings such as passive houses has been the empirical focus for a number of studies drawing on a range of concepts such as transition management (Killip, 2013; Rohracher, 2001; Scrase & Smith, 2009), strategic niche management (Heiskanen et al., 2015; Lovell, 2007; Mlecnik, 2014; Quitzau et al., 2012; van der Grijp et al., 2019), the multi-level perspective (Berry et al., 2013; Gibbs & O’Neill, 2015; Rohracher & Späth, 2014) or technological innovation systems (Faber & Hoppe, 2013; Ornetzeder & Rohracher, 2009).

However, this transition perspective with its focus on radical systemic change does not seem to adequately capture the very gradual shifts in the construction sector observed in Sweden. Also, the alternative approach of analysing the uptake of passive houses as a diffusion process (Rogers, 2010/1962) falls short of capturing the characteristics of this development. Concepts of technology diffusion work best under stable context conditions where traditional buildings are eventually substituted by low-energy buildings, but they are rather blind to systemic reconfigurations such as new forms of collaboration, new industry structures or new forms of regulation, which characterize the dynamics of the Swedish construction sector. While a radical transition to passive houses thus does not seem to take place in Sweden, the low numbers of certified passive houses in Sweden do not reflect the changes in the construction sector either.

In this article, we aim to better understand the gradual shifts in the established practices of housing construction through an analysis that is more sensitive to the change and adaptation processes we observe in relation to passive houses in Sweden. We analyse the introduction of passive houses as a process of mainstreaming, meaning a normalization process in which passive houses increasingly become more common and accepted – not only as a new product through its increased adoption but also through gradual institutional adaptations and new socio-technical configurations around very low-energy buildings. This normalization process entails battles over both the meaning of the passive house concept as well as how and where these buildings are to be introduced in the housing sector.

Three key domains where mainstreaming of passive house development is taking place have been identified in the empirical material in Sweden: policymaking and regulation, regional socio-technical contexts and the discursive understandings of the passive house concept. We hope to contribute to an understanding of the introduction of green technologies and concepts more broadly, as such gradual regime reconfiguration processes which do not result in radical change are widespread in this field.

2. From radical transitions to mainstreaming as negotiated change

As pointed out above, the concept of transitions as systemic innovation and radical transformation of socio-technical systems has been widely used to understand the ongoing transformation of the building sector towards greater energy efficiency and reduction of greenhouse gas emissions. The multi-level perspective of innovation has arguably been the most influential theoretical framework in this field (Geels, 2002; Rip & Kemp, 1998). The concepts of socio-technical niche, regime and landscape (and the interaction between these levels of structuration) are central in transition studies. Niches are protected testbeds of new technological solutions, shielded from selection processes in the regime, while the socio-technical regime represents the established system with its social norms and rules, sectorial structures, etc. Regime structures explain the remarkable stability of established socio-technical systems and the incremental innovation and optimization processes they comprise, while emerging niches represent potentially radical alternatives which may eventually lead to a fundamental overturning of established regime structures as we have seen for example with the disruption of earlier mobility regimes through the introduction of the car.

Without a doubt, passive house development can be analysed as the emergence of a new socio-technical niche that challenges existing regime structures (Mlecnik, 2014). What has been less explored empirically, however, is the dynamics between niches and regimes and the types of change unfolding not only in growing niches but also in the respective regime (building sector) as a consequence of niche-regime interactions. Smith (2007, p. 431) asks in this context for a ‘theory of linking’ between niche and regime developments. Conceptually, Geels and Schot (2007) have shown how very different types of transition dynamics or pathways of change can unfold dependent on the timing and nature of interactions between niches and regimes. This typology opens transition concepts up for more gradual dynamics of change, such as transformation or reconfiguration pathways where regime structures largely remain intact or are gradually reconfigured by adopting elements from radical niche technologies, such as passive houses. Smith and Raven (2012) in turn, conceptualize different dynamics of niche-regime interactions from the perspective of niche actors, who may resort to strategies of ‘fit and conform’ by furthering niche development within existing sectoral structures or of ‘stretch and transform’ where the strategy is to change and adapt regime structures to the requirements of niche configurations.

In our analysis, we are particularly interested in how new sustainable building concepts such as passive houses become partially integrated into the established construction sector through institutional change and technological adaptation – not by eventually overthrowing it. Moreover, the emergent networks and initiatives around passive houses which we study can hardly be described as ‘strategically managed niches’, as Lovell (2007) also observes for the UK low-energy building sector, and direct uptake of innovations from demonstration buildings is often barely visible (Heiskanen et al., 2015; van der Grijp et al., 2019). Moreover, it is far from clear at this stage whether these new building technologies will eventually lead to a full-scale transformation of the housing sector.

We find these processes of gradually adopting selected elements of alternative building concepts more appropriately described in the mainstreaming approach put forward by Berker (2010) and Sørensen (2015). Berker studies two strategies that innovators employ to deal with uncertainties: substitution and mainstreaming. Substitution as a strategy means the replacement of existing technology with new, innovative technology. In contrast, mainstreaming as a strategy aims to incrementally improve existing solutions and is more focused on adapting to local conditions rather than striving for standardized solutions for different markets. The core understandings of the role of negotiation and adaptation in implementing technologies draw on Berker’s use of the concept.

Sørensen (2015) takes the idea of mainstreaming further to study the incorporation of small-scale and sustainable technologies into established industry sectors. As the analysis of several cases of ‘alternative’ technologies promoted by grassroots movements show, many of these technologies (wind turbines, electric cars, ecological architecture) have meanwhile become an element of established sectors without fundamentally altering them. Sørensen highlights that mainstreaming is processual and diverse: for the same innovation, technological changes are central sometimes, design changes at another time and conceptual changes at yet another point in time. Consequently, this diversity entails many different negotiation processes. The characters of – and tools for – negotiation thereby differ depending on where in the process and in the timeline they take place. Importantly, both Berker and Sørensen emphasize that the outcome of mainstreaming is open and the process could mean that alternative ideas take over or that they adapt to existing solutions. The process is gradual, shifting and depends on different actors negotiating innovation and change at different places and times. Thus, the identification of relevant practices and domains of negotiations are of great importance for the perception of the mainstreaming phenomenon.

In recent years a small but growing body of literature has begun conceptualizing socio-technical change towards low-carbon and low-energy buildings as such a process of mainstreaming. A special issue of Buildings & Cities has focused on the role of mainstreaming zero-carbon solutions in built environment education and training, showing successful examples and models of how education and training can ensure the creation of zero-carbon built environments (Stevenson & Kwok, 2020). Fastenrath and Braun (2018) present the historical development of incorporating passive houses in Freiburg, emphasizing the role of integration in land use planning processes. Niskanen and Rohracher (2020) shows how investment calculations, energy models and collaboration strategies play a key part in facilitating mainstreaming in Swedish housing companies. And Figueiredo and colleagues (2020) show how leading regions in Austria, Belgium and Germany have become successful in mainstreaming passive houses through for example local and regional governments promoting long-term policy instruments and regulatory frameworks or vocational training programs.

In this article, we thus analyse the development of passive houses as a process of mainstreaming through the gradual re-organization of the Swedish construction sector rather than a radical transformative change process or simple product diffusion. Despite this different focus, we see this approach largely in line with the ambition of transition concepts. In their overview of sustainability transition literature, Markard and colleagues (2012) have identified four main fields for future studies: further elaboration on ongoing transitions; understanding the politics involved in transitions; more focus on the agency of different actors; and the need to consider geographical dimensions. We see our approach in line with these demands by focusing on context-specific negotiations between relevant actors in ongoing processes of change. Just as in transitions, such processes are ‘likely to unfold unevenly through sudden advances and setbacks, depending on changing coalitions and contexts, unintended consequences and learning processes’ (Geels et al., 2016, p. 911).

We address mainstreaming empirically as well as conceptually in order to learn more about how normalization of low-carbon and low-energy buildings takes place in practice through negotiations in different domains. These negotiations as key practices in understanding the implementation of passive houses in Sweden are studied in the domains of policymaking, regional socio-technical development and the construction of discursive understandings of the concept. This conceptualization has several effects: first, it means that the term negotiation is broadly understood as all the practices in which relevant actors compete to identify and establish the material and discursive properties of passive houses. Second, it means that negotiations differ in expression and method: relevant actors ‘meet’ differently in the public debate, in the policy process, at the construction site, or at the architects’ office. Finally, this means that different negotiations might need different theoretical conceptualizations to be fully understood.

3. Methodology

Our empirical research has been set up as a multi-case study. In a first step in the years 2014–2015, passive house projects in Sweden were identified through scanning of newspapers, policy documents, the Swedish Passive House Center data and the national low-energy building database ‘LÅGAN’. Through this material, three particularly pertinent domains were identified where mainstreaming was enacted through the negotiations of relevant social groups: the domain of public discourse, the domain of regional networks and institutions and the domain of regulation and policy making. The word ‘domain’ is used to describe a subset of the buildings sector with its own rules for negotiation: in the public discourse negotiations take place through debate posts and conversations in the news media where actors aim to convey specific passive house depictions, institutional milieus depend on the competition and cooperation between different players resulting in regional specifics of the housing sector and in the policy making process different actors shape legislation by presenting their arguments for the specific design of particular laws.

In a second step during the years 2015–2019, the three domains were researched through interviews and the reading of documents. The study design is shortly presented here – a more in-depth description of the specific methods can be found in (Niskanen, 2018). All documents and interviews were transcribed and coded. Based on recognizable patterns and relationships, the initial codes were merged into broader themes: for example ‘the historical development of passive houses in the Western region’ or ‘the introduction of the energy performance of buildings directive in Sweden’. Finally, these themes were analysed in order to identify relevant negotiations in each domain.

To study negotiations in the public debate, 1418 business paper articles and 385 national and local newspaper articles have been studied through textual analysis (to identify common themes and patterns), focusing on how housing companies, politicians or interest groups and other relevant actors present passive houses from a socio-technical, economic and ecological perspective.

To study regional negotiations, two regions were identified as interesting to compare: western and eastern Sweden, where the first is characterized by a comparatively large number of passive house forerunners and the second by a low uptake of these buildings. Through interviews with 21 key actors and textual analysis of local policies and local newspaper articles, institutional support for passive houses regarding funding, competence and political strategies were studied (see appendix A for a list of interviewees and newspaper articles). Choosing two different regions allowed us to differentiate how regional settings are negotiated and how this affects passive house development.

Finally, to understand negotiations in the policy process, four major Swedish housing policy proposals and 183 statements from the ensuing public referral process have been textually analysed to identify the role played by the passive house concept in the formation of policies and regulations. In these referral processes, affected actors may respond to legal propositions as part of the law-making process. Referrals are thus an important aspect to understand negotiations about new laws and regulations.

4. Results

In this section, we discuss the enactment of mainstreaming through negotiations in the three domains identified in the process of empirical analysis: public discourse, regional networks and institutions and national building norms.

4.1 The mainstreaming of passive houses in public discourse

A first domain where passive houses became increasingly integrated into the established housing regime is the news media. This subsection identifies different framings of passive houses in newspapers and the business press in the 2001–2018 period (see appendix A for a list of newspaper references). By framing we mean the understandings and perceptions of a phenomenon that people hold and use to understand and shape reality (Goffman, 1974). Specific aspects of reality are highlighted in frames and have precedence in the characterization of a phenomenon, leading to a specific problem and solution formulations (Entman, 1993). We use the concept of framing conceptually to highlight how actors communicate about passive houses and we analyse framings to understand how passive houses have been negotiated in public discourse. With Pinch and Bijker (1984) we also argue that the interpretative flexibility of competing for passive house framings can in turn be stabilized through a rhetorical closure. This closure leads to a few (temporary) stable understandings of what passive houses entail and what roles they play in the worlds of the relevant actors.

Even as the passive house concept has part of its origin in Sweden (Müller & Berker, 2013), very few of these buildings were built early on in the country and they were hardly visible in the news media in the first decade. Only between the years 2006 and 2009 did passive houses gain more significant national attention. At least up until the 2009 Copenhagen United Nations climate meeting, Swedish environmental politics were dominated by ideas that the country would be world leading through investments in green technologies and export (Anshelm, 2012). In line with the zeitgeist, passive houses were presented in newspapers as ecologically sound and as part of the electrified solar cities of the future. This sustainable society frame presented passive houses as both rooted in the architecture of 1970s eco-villages and in highly technical avantgarde architecture. This framing suited many actors, for example progressive city planners and politicians who could present attractive visions of green urban utopias, environmentalists who could promote a truly sustainable building solution, and parliamentarians presenting Sweden as an international powerhouse of the green industry. In this representation, passive houses were the symbol for a radical change to a truly sustainable society.

Over time as passive houses became more common and the debate focused more on specific passive house projects and the integration of passive houses in existing energy systems, this framing lost its more dominant position and a frame with a more local focus took hold. Swedish municipalities were early adopters of passive houses (LÅGAN, 2020), and these buildings played a central role as they lobbied for stricter energy performance requirements in their positioning as ‘green municipalities’. These municipalities presented themselves as sustainability pioneers, who took environmental responsibility while the established construction companies went on with business as usual. Through this local pioneer frame, the functionality of passive houses and specific technical characteristics came into focus as politicians and public housing companies highlighted that passive houses were qualitatively different from traditional buildings. These buildings required more insulation and more energy-efficient building components, but they were also presented as being more comfortable homes.

With the establishment of a Passive House Center in the city of Alingsås in 2009, the development of standards for passive houses took hold in the public debate. One main result of this early attempt of formalizing the concept was the development of a Swedish Passive House standard (FEBY). In this formalization frame, passive houses were to play a key role in achieving local and national energy-, climate- and building policy objectives. In this framing – co-existing with the previous framings – low-energy passive house principles were presented as an innovative break with conventional unsustainable practices in the construction industry, and it was promoted to become a new national building code standard. Through this, the passive house concept was picked up by more mainstream market actors and it was absorbed into the mainstream construction sector – the ‘radicality’ of the passive house concept turned into a selling point.

Many of the larger construction companies questioned whether mandatory passive house principles would really lead to increased sustainability in the housing sector. Sweden’s four largest construction companies at the time framed passive houses as one of many low-energy or green building products. These companies wanted to be able to position their own building types as the market leader in the green building segment and they mobilized the passive house moniker to market less radical low-energy buildings through the industry-backed environmental certification agency the Swedish Green Building Council. A sole focus on passive houses was deemed as a potential market barrier for the large-scale development and construction of low-energy buildings: ‘Passive house technologies put special demands on projectors, builders and residents. Nationwide companies experience difficulties in maintaining consistent quality between different parts of the country’ (Harryson, 2009, p. 1). This market framing of passive houses ought to be understood as part of a wider struggle over the emerging green building niche market. A less regulated housing market with a diversity of low-energy building types was also promoted by the National Board of Housing, Building and Planning. The main argument was that passive houses were an unnecessary nuisance for a national energy system already deemed to be ‘close to climate neutral’, but at the same time in need of higher construction volumes.

A more market led development of low-energy buildings helped normalize the passive house concept in the debate, as the concept was often used as a reference point in explanations and discussions on energy efficiency in buildings. While one key building principle of passive houses – the limited installed heating capacity – was not adopted by traditional market actors, other basic passive house principles were included in mainstream building practices: such as increased floor-, roof- and wall insulation, limited cold bridges, passive solar heating and highly insulated windows (Kiss & Neij, 2011). At the same time, the passive houses developed during this period had installed a greater heating capacity. This positioned passive houses closer to more conventional buildings in the market, but it also helped bringing the topic of energy use into the main discourse on the development and construction of buildings.

Summing up, passive houses went from being framed as an innovative breakthrough technology with strong ecological values to being absorbed by more mainstream narratives about low-energy buildings and energy efficiency norms. During the 2001–2018 period, development of different low-energy building concepts took place and the constructed area of all types of ‘low-energy buildings’ went up nationally from 5000 m² to 1.1 million m² (LÅGAN, 2020). While passive houses never were the dominant theme in the low-energy construction debate, they played a part in influencing and shaping the debate through an increased focus on energy use.

4.2 Mainstreaming as alignment of regional innovation systems

Another domain of mainstreaming was found in the context of regional development. This regional domain refers to a whole ecosystem of conditions that may favor the development of passive houses – the supportive role of regional politics and public administration, the availability of competent supplier companies, construction companies with appropriate business models for passive houses, the establishment of networks of cooperation, the knowledge and expectation of various regional actors and stakeholders, etc. (see appendix A for a list of interview references). This entails a focus on connections between political institutions and relevant housing- and energy-actors and their networks (Coenen et al., 2012; Truffer, 2008).

The regions of western and eastern Sweden differ in their historical development regarding passive houses. The first is considered the birthplace of the passive house concept in the country and passive houses are more common in the region (LÅGAN, 2020). Moreover, it is the location of Sweden’s only Passive House Center in the town of Alingsås. In contrast, the eastern region has a very low uptake of passive houses and is dominated by a strong publicly owned energy utility providing a main part of the region with district heating (Palm, 2004). In the western region, various companies re-oriented their organizational processes towards the affordances of passive houses, such as the need of a more sophisticated energy modeling, a closer integration of the design and construction process and its actors or new ways of calculating long-term economic viability. Housing companies in the eastern region have been more hesitant to scale-up passive house development and rather want to demonstrate their ability to produce highly efficient buildings without re-organizing their way of doing business.

In the frontrunner western region, the introduction of passive houses was accompanied by the buildup of an alliance of private construction companies, public housing companies, passive house enthusiasts and local and regional policymakers. Since the 1970’s, a small group of supporters of alternative building and energy solutions in the region questioned the excessive consumption of energy in the housing sector and started experimenting with solar energy and different early low-energy building solutions (interviews former CEO of Eksta, 2015; NCC, 2016). Many of these enthusiasts have had a long-term impact on the development of the housing sector in the region. For example, Sweden’s most famous passive house proponent – architect Hans Eek – was one of the founders of Efem architects in Gothenburg, a company that specialized early in designing eco-villages and built a ‘passive solar house’ already in 1978 (interview Eek, 2016). Later, he was central in establishing the Passive House Center in Alingsås.

Public housing companies and strict local energy performance policies have also been central for reconfiguring the regional housing sector and its institutional environment in the western region. Key factors have been a regional government funding low-energy building programs, local politicians implementing strict energy performance requirements, private and public companies constructing less resource intensive buildings and tenants being engaged or successfully convinced (interview NCC, 2016). Previous research shows that local governments can play key facilitating roles in the implementation of sustainable building solutions (Kivimaa & Martiskainen, 2018; Ornetzeder & Rohracher, 2009; Smedby & Quitzau, 2016). Municipalities in the region took up such a facilitating role as they developed loose knowledge networks where private and public actors gradually built competence around passive houses projects. These projects engaged several regional key players such as small building companies, some large national construction companies based in the Gothenburg area, Chalmers Technological University and researchers at the Technological Institute of Sweden.

The Passive House Center played a key operational role in the western region and gave institutional stability to the networks. The Center was the leading passive house competence hub in Sweden in the 2010–2018 period, acting as project managers, taking on architectural responsibilities, leading EU research projects, organizing conferences for builders and planners and also disseminating passive house knowledge nationally. Through its roles and its networks, they offered a ‘narrative for focusing capital and other resources’, an important aspect of establishing passive house regions (Späth & Rohracher, 2010, p. 451).

While the Passive House Center was a central operative actor, it was also guided by the strategies (and funding) of the Western Regional Council. The council put in place a green growth program in the early 2000s with two specific focus areas: biogas and passive houses (Lindsten, 2010). This program included dialogues with 49 municipalities, leading to a reconfiguration of how many municipalities worked internally to ensure local rules facilitating the construction of more energy-efficient buildings.

Despite the comparative successes of the western region, institutional mainstreaming of passive houses has been an uneven process in Sweden with great regional differences. In the eastern region, in comparison, a normalization of passive houses has not yet taken place. We argue that this depends partly on the lack of local and regional institutional support of passive house deployment. The lack of enthusiasm for building efficiency can in part also be explained by the central role of municipal utilities such as Tekniska Verken AB, situated in the region’s largest city of Linköping, and their strong investment in district heating infrastructures. In this context, it was more favorable to work for the provision of sustainable heat than for the reduction of heat demand through efficient buildings. Still, there have been several passive house deployments in the region.

In the eastern region, municipal and regional planners present detailed accounts of what they consider to be institutional barriers to entry. There are few engaged SME’s developing buildings for the local and regional market; public companies in the region lack joint strategies for the development of passive houses; passive houses are described as potential nuisances in regional policies: ‘ … new low-energy buildings … place new challenging demands on district heating in the future’ (Östsam, 2014, p. 18); and, finally, municipal actors in Linköping claim that there is a tradition in the municipality to play it safe and follow legal minimum building energy requirements rather than push for innovations. Despite this lack of targeted institutional strategies, the passive houses built in the region have all been developed or supported by local municipalities or the regional government as part of their environmental policy objectives.

In sum, despite the differences in creating regional environments for passive houses between the two regions, a common feature is that passive houses are part of the broader institutional and political context of the region and not a radical outlier or niche. The network of energy-conscious SMEs, the competence building and political support in the western region also were at the service for the whole construction sector, just as many of the dedicated passive-house-companies were municipally owned and part of the establishment rather than radical newcomers.

4.3 Standardizing low-energy buildings through national regulations

Gradual processes of mainstreaming can also be observed in a third domain: a rather incremental shift in the building code and regulations despite radical rhetoric of carbon-neutral buildings. We studied the introduction of the European Energy Performance of Buildings Directive (EPBD) into national law in Sweden. The EPBD presents a framework for implementing so called nearly-zero energy buildings (nZEBs) in the EU but allows for country-specific flexibility. The Swedish Energy Agency and the National Board of Housing, Building and Planning were both tasked by the Swedish Government to work out a suitable nZEB definition for Sweden and a plan for how to merge this with the national building code. We have analysed relevant documents and policy proposals produced in this process together with 183 comments on the proposals from all major Swedish construction sector stakeholders as part of the law-making process and identified two main controversies with relevance for passive houses and their fit with nZEB standards.

The first controversy was acted out between Swedish authorities and concerned with the setting of a mandatory energy performance level for nZEBs. The Ministry of the Environment (based on Board of Housing data) and the Energy Agency each presented proposals for minimum energy performance requirements for nZEBs in 2010–2011. The national agencies argued for different calculation methods and used different data sources and systems of accounting for nZEBs in Sweden. The Board of Housing made use of economic statistics, the flexibility provided by the EPBD for defining cost-optimal levels of energy performance and the aim of keeping the costs of additional building efficiency below the predicted cost of new low-carbon electricity production in Sweden. The result was a suggestion for the minimum energy performance requirement for nZEBs of 90 kWh/m²/year which was almost the same as the existing national building standard. In contrast, the Energy Agency made use of national environmental objectives, data from municipal passive house demonstration programs and encouraged the inclusion of demands on better building envelopes and alternative energy sources in the building code. Hence they argued for a much lower minimum energy performance requirement of 55 kWh/m²/year. This had also the support of several municipalities which already had implemented programs for energy-efficient buildings such as passive houses. In 2017, a version of the Ministry of the Environment proposal was passed as a national law. The law meant a lenient energy efficiency requirement on buildings (compared to the requirements in passive house certifications), with a gradual tightening of the performance of buildings. Despite the outcome of this process, passive houses were an important reference point in the negotiations about the future of the Swedish building sector.

In 2015, a second controversy arose as the Board of Housing presented a report with definitions and guidelines for the energy performance of buildings to be incorporated in the national building code. The controversy focused on how to calculate the energy performance of buildings and what elements to include. The Board of Housing report presented different potential system boundaries for calculating building performance. Should for example renewable energy generated on-site (e.g. through PVs) be regarded within the boundaries and thus reduce the energy demand of the building? The Board of Housing settled on a system boundary called ‘delivered (purchased) energy’ (Board of Housing, 2015, p. 7) which means that only energy from external sources delivered to the building's technical systems (heating, warm water, etc.) should be considered when calculating the buildings energy performance. Energy generated at the site of the building would be considered within the building boundaries and reduce energy demand. Obviously, such definitions also interfere with power constellations and interests in the housing and energy sector. The suggested solution favored heat pumps (making use of on-site energy) but disfavored district heating (a major player in the Swedish heating sector). In the further policy process, various actors thus weighed in with their position and achieved the inclusion of a ‘weighting factor’ for electricity which shifted the balance from heat pumps to district heating. Consequently, building performance became a down-prioritized issue.

The seemingly neutral Swedish definition of ‘nearly-zero energy buildings’ – which as we pointed out was nevertheless imbued with politics and interests – had a significant impact on the pathway of the housing stock and was definitely not in favor of a significant shift towards passive houses. Such developments are clearly in line with a tradition of Swedish climate policy making where much weight is put on finding consensus with large corporate actors on policy measures and strategies (Kronsell et al., 2019). Again, we see how the concept of passive houses or nZEB becomes a driving force in the domain of building regulation, but then does not lead to massive changes and instead is gradually assimilated into existing sectoral structures.

5. Concluding discussion

In the previous section, we have described three domains where the Swedish construction sector undergoes piecemeal systemic changes as a reaction to low-energy buildings becoming more widespread and normal. The first of these domains we investigated was the realm of public discourse where we identified different framings and narratives (Entman, 1993; Goffman, 1974) of passive houses. Over time these framings shifted and went from presenting passive houses as radical and advanced alternatives for a future low-carbon society to understandings of passive houses as a specific market segment with particular qualities and disadvantages. Passive houses lost their role as radical counter-imaginary of the construction sector, as they became reframed and redefined by softening the standards required to call a building a passive house. Other energy-efficient buildings which were part of the portfolio of ‘normal’ buildings and share certain qualities of passive houses (high insulation, heat recovery, etc.) also became part of the description of standard low-energy buildings in the sector.

Another domain was the regional socio-technical system related to buildings – the technologies used and types of buildings constructed, the competencies developed and available with regional actors, the establishment of networks of competent actors around low-energy buildings, the establishment of intermediary actors coordinating the development of (certain segments of) the construction sector, the familiarity of tenants and building owners with different types of buildings and the regional political support invested in shaping the housing sector. As with public discourse, passive houses did not become the new normal, but they became the energy-efficient end of a spectrum of well-established building types and had an influence on reconfiguring the whole construction sector and its regional context. A salient feature was however the geographic ‘unevenness’ of this development with certain regions or cities developing eco-systems for low-energy buildings and others lagging behind.

The final domain investigated was the building code and regulatory standards for buildings, where we also found processes of gradual change and adaptation of the whole sector, but no decisive shift towards passive houses. In this domain, nearly-zero energy buildings and passive houses were at the center of controversies and negotiations about future performance standards of buildings. Instead of making passive houses the benchmark for new buildings, definitions of performance levels and ways to calculate building performance were tweaked and renegotiated in ways to accommodate established structures and interests of the construction sector such as the dominance of district heating. Again, we rather see a partial adaptation of construction sector structures with passive houses as an important reference point in negotiations and controversies.

These processes are rather in line with the concept of mainstreaming presented earlier than the management of an emerging niche. What we could observe so far in our case was the adaptation and assimilation of formerly radical alternatives by the established construction sector and not the substantial growth of a separate passive house niche or a replacement of the regime by new alternatives. In a sense, radical passive houses were domesticated and lost their radical edge, but at the same time, the construction sector became reconfigured and normalized requirements for low-energy buildings. How far this domestication would go and to which extent the whole building sector would need to adapt to radical demands of zero-carbon was however an issue of negotiation, controversies and politics. We do not claim that this scheme is equally followed in other areas, but it appears to be one possible pathway of socio-technical change towards more climate-friendly solutions and structures. In Geels and Schot’s (2007) typology of transition pathways, the changes we observe in the construction sector lie somewhere between a transformation pathway (with the established regime architecture remaining intact) and a reconfiguration pathway (where elements of the alternative solutions adopted eventually reconfigures regime structures).

Analysing passive houses as a socio-technical niche would have made it difficult to capture the lack of clear boundaries between a passive house niche and the established building regime. Along with this we also do not observe significant growth of the niche by developing internal structures and stable configurations. In our case, the niche is constantly ‘seeping’ into the regime and passive houses eventually become normalized in different domains. Sector structures such as discourses around sustainable buildings, regional innovation systems around low-energy buildings, building codes and regulation, eventually accommodate these developments. In consequence, passive houses remain a very minor fraction of new houses built in Sweden and it remains unclear whether they will ever become the standard of buildings in Sweden. Nevertheless, they have been a driving force for the restructuring of the construction sector even without significant niche expansion. What we find in our case is thus a specific form of linking between niches and regimes, as requested by Smith (2007), which leads to a particular pathway of change.

There are several more characteristics highlighted by the concept of mainstreaming. In contrast to a transition perspective, the focus of mainstreaming is more on ongoing activities and processes and less on outcomes. The innovations we find in our study are mainly organized around specific problems and require local and multi-actor solutions. While a stable new regime configuration is at least implicitly part of the transition concept, processes of mainstreaming are open-ended and less coordinated. Even if policymakers might have a strategic view of the problem such as the implementation of the EPBD in a Swedish context, such problems break down into smaller local problems when being translated into solutions. Mainstreaming can thereby lead to different types of normalization of radical alternatives without necessarily resulting in radical change.

Such a focus also has implications for the mix and design of policies aiming to achieve a low-carbon construction sector. While a transition-oriented policy rather would have its focus on the protection and growth of a passive house niche and on staking out long-term objectives and transition pathways, policies informed by a mainstreaming perspective would pay increased attention to the incremental and short-term changes and micro-political struggles in the established building sector. The three domains we have identified in our analysis of passive house development could be arenas for such political interventions. The gliding of passive house discourses from radical alternatives of the built environment into a techno-economic framing could for example receive more attention in the policy making process. The way passive house discourses are framed in the policy discourse can play an important role in maintaining pressure on the established building sector to adapt. Also, questions of how to calculate building energy performance are often left to experts and interest groups without acknowledging the extent to which these calculations are congealed politics and contain decisions about further transition pathways. The importance of regional innovation milieus also demands more attention to local and regional politics (and in consequence multi-level governance arrangements and national policies designed with sensitivity to regional differences) which facilitate experimentation, the establishment and funding of intermediary organizations such as the Passive House Center or the implementation of regional building programs with stricter standards than national requirements. Moreover, it highlights the need to integrate industry-oriented policies with environmental and low-carbon building policies.

In conclusion, we can thus say that a mainstreaming approach captures incremental reconfiguration processes in the Swedish housing sector while keeping the outcome of the normalization of passive houses open. Mainstreaming focuses on the negotiations taking place at different transition domains between relevant actors. Analysing mainstreaming activities is particularly helpful for a better understanding of ongoing changes which happen in a rather uncoordinated and unmanaged manner, but which still may contribute to gradual systemic change. This lack of systemic coordination is also reflected in the policies which have been involved in the mainstreaming of passive houses in Sweden and which did not pay sufficient attention to incremental change processes in the established building sector such as the politics of regulatory design, the creation of innovative regional milieus or the framing of discourses of low-carbon housing.

The main limitation of this study is its focuses on a few specific domains of the Swedish housing sector. Future research could benefit from adding other domains such as the use of certification schemes, as well as from comparisons with development in further Swedish regions and other countries. More broadly, we see a need for more empirical studies on the relationships and linking between emerging niche configurations and established regime structures also in other fields than the housing sector. Such studies would provide a stronger empirical grounding to pathways and dynamics of socio-technical change.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This paper is funded by research project grants from the Swedish Energy Agency (Energimyndigheten).

Notes on contributors

Johan Niskanen

Johan Niskanen is a postdoc at the Department of Technology and Social Change at Linkoping University and his research is concerned with how perceptions of energy and environmental change are transformed into practice, focusing on sustainable innovations and circular economies.

Harald Rohracher

Harald Rohracher is professor at the Department of Technology and Social Change at Linkoping University and his research deals with infrastructural change particularly in the field of energy systems – the introduction of renewable energy technologies, sustainable and energy efficient buildings, or the transformation of electricity grids.