Built territories. Innovative regeneration processes for a participatory and sustainable design

Abstract Today we must definitively face the challenge of modified urban scenario, with a great presence of abandoned buildings that losing their stable function, often become reason of social tensions. The implementation of design processes to reverse this trend, called “architectural project for existing buildings”, requires innovative methodological approaches with simultaneous input of multiple knowledge and new interaction between design and sustainability. This proposal means to trace the profiles of some recent experiences characterized by the experimentation of alternative design procedures where the active participation of civil society becomes crucial. These planning practices must re-find their roots in the teaching practice, reclaiming the critical role of the education for setting up a design for the new generations. In this way, the experience of LABZONE2 (Politecnico di Milano) is oriented to develop urban regeneration design by activating a social condensers network in the Town Hall 2 (the most multi-ethnic of the city of Milan).


Introduction
Today we must definitively meet the challenge of the inheritance of urban scenarios which are the results of socio-economic conditions very different from the current ones : from the indiscriminate growth of the city during the economic boom age, to its planning by functions, etc. (Borja, Castells, 2002, p. 14). It is a huge presence of abandoned buildings that take up space, often becoming reason of social tensions. They are buildings that have lost stable functions, becoming empty spaces which future should be re-invented through voluntary initiatives, not planned or otherwise planned.
The configuration and implementation of design processes to reverse this trend, made by innovative methodological approaches, is an emerging topic for the definition of alternative methods of interaction between design and sustainability, aimed at the development of changing practices of regeneration of built areas and its social-economic and cultural organization. This redesign, that we call architectural project for existing buildings, involves new modes of vision of the relationship between man and urban space and requires the simultaneous input of multiple knowledge, towards the definition of renewed phenomena of practices of appropriation and use of built territories (Borsotti, Campanella, 2014).

Know or re-know: design for the existing built in the contemporary scenario
The definition of new geographies of centrality and marginality produced by global phenomena has the most sensitive receptor in the urban texture with direct implication on the urban asset. Today the built heritage is in fact at the center of a new and difficult redefined complexity that moves in constant tension between preservation and transformation of places (Sassen, 1997, p. 154). Despite this, the great unused built heritage of our cities represents a big potential resource: from one hand the transformation is necessary and cannot be postponed; from the other hand, in a context where the changes take place rapidly and on a large scale, it is essential to search for representative elements of a collective identity. As underlined by Levi Strauss, the identity is now more than ever to be considered: "not as a reactivation of a compact and monotonous ego, but rather as a control of the centrifugal and dispersive tensions present in relation between subjects interacting in the places: an issue of flexible and dynamic management of multiplicity" (Levi-Strauss, 2003).
The identity of these places is therefore a dynamic system, constantly rewriting and so changing, in relation to the changing of the context. The great challenge that today we have to face regards the construction of models able to provide answers. In this way, the built heritage becomes today an experimentation area where testing the social dimension of architecture. Here the design has to deal with "diversity", transforming it into a resource, taking the values of the past to make them a trigger of change (Pistidda, 2015, p. 21).
De Certeau defines the space as a "used place" (De Certeau, 2001) and it is precisely the concept of colonization and use that adds value to the project. Spaces that are now silent containers can become reconstruction spaces able to repair the fragmentation.
In this perspective today the abandoned heritage has more than ever a fundamental and structuring value, as it becomes metaphorically a kind of "cultural backbone", able to define reference points in the transformation process (Carta, 1999, p. 20).
The project for the existing built becomes a tool able to regenerate abandoned buildings and disused urban complex through innovative socio-economic and usage models, by re-placing them into the vital urban cycle. Protecting the permanencies does not mean to impede the transformation, but to act in synergy with it. It means not reduce and simplify, to recognize all the elements that make the diversity and deal with them, in new way of observing that goes beyond the macroscopic evidence (Viganò, 1998, p. 190). 2.1 Design social-oriented: a key for the transformation The speed of dynamics of transformation today requires a flexibility of action and a complementarity of the viewpoints, in an interdisciplinary dialogue. The need to shift the focus from an architectural issue to a more complex and integrated one, requires an openness to the complexity. The diversity is now a structuring condition of the current urban settings and its defense becomes an ethical issue that the project for the existing built try to face.
This speed has direct implications on the social dynamics of the cities. How to combine a progressive integration, by reducing the cultural vulnerability of the existing and future urban communities? Today the unused spaces are more and more a "point of contention" and sometimes they become a conflictual place.
Today the design for the existing built have to take responsibility for this dimension, for the changing relationship between man and urban space. Therefore it is necessary that the research/action approach is oriented: -to the definition of architectural and social models for the re-use of existing spaces able to implement, through a functional mix, synergies between the different actors involved, also through participation processes and social aggregation mix; -to the architectural and urban regeneration of the existing built, also considering the economic sustainability of the proposals.
The abandonment of the built heritage and the consequent progressive degradation has a direct impact on the social and urban dynamics of the surroundings, contributing to generate sensitive territories. The process of collective re-appropriation of the unused buildings plays a key role to ensuring the success of operations. In this way, the user-led design methodology helps to establish synergies between the different actors involved, promoting the participation and the construction of a system open to the local community through the promotion of care culture that directly involves people in the conservation process. The implementation of reuse models developed through participatory processes contributes to develop open innovation systems, based on collaboration and sharing (Manzini, 2015).

The design for existing built as social "device": tools
The design for existing built, assuming the human and social resources as main components of the urban and territorial texture, appears as a real social device, thus becoming a benchmark for the management of transformation. The final goal is to build an interpretative process that, starting from the understanding of the places, defines strategies and actions to ensure a "right to the city for all" as main way of inclusion (Burns, Cottam, Vanstone, Winhall, 2006).
The development of knowledge, the activation of a care process and the construction of participation are intermediate steps that make use of different tools: -Desk and Field Research: it includes the activate listening of the instances raised by the partners and stakeholder involved, even by comparison with similar Italian and European realities, as well as actions of study and monitoring: -Problem testing: systematization of resources and problems, identifying innovative models of interaction between associations, informal group and individuals, also through the development of App and technologies for the social survey (crowd-sensing). Through open days dedicated to the inhabitants, questionnaires, seminars, think thank it is possible to build participatory processes that can act as accelerators of ideas.
-Problem solving: the suggestions collected can be translated in operational actions and real project proposals, supported by economic models.

Some paradigmatic cases study
In the last 10 years many experimentations have been tested all around Europe. In fact, the scenarios generated by the economic crisis have led researchers, designers and civic associations to promote new practices for using and redeveloping neglected urban spaces. Participatory design, co-design, social innovation, public-private partnership are the key-words of a new approach which finds a common ground within the reflection about temporary uses, and whose promoters are very often the designers themselves (Inti, Inguaggiato, 2011 The project was organised as an interdisciplinary platform for research and public intervention in order to trigger a debate amongst architects and planners, pinpointing many unplanned uses of neglected and detached spaces which generate informal economies out of the borders of traditional urban planning. Many events have been organized, in order to develop strategies for integrating such processes into the design of contemporary cities, where citizens are the promoters rather than the final users of urban changes (Oswalt, Overmeyer, Misselwitz, 2013).

ZUS-Zones Urbaines Sensibles. A creative approach
In more recent years, the design of the Luchtsingel bridge in Rotterdam properly shows low cost methods and practices for «making the city» today in neglected central areas. The initiative is born within the fitfth International Architecture Biennale of Rotterdam (IABR), where the design studio ZUS-Zones Urbaines Sensibles, co-curator of the 2012 edition, has promoted, together with some local stakholders, the use of alternative financing tools and design methodologies in order to bring back people and activities to the so-called "Test Site Rotterdam" area ( The test run by ZUS in based on the construction of the Luchtsingel, a wooden pedestrian 350 metres long footbridge connecting Rotterdam North with the city centre. It is a light infrastructure which invites people to frequent neglected places in a different way (it crosses the railway that splits the area in two) and becomes a catalyst for the local economic growth. To build the bridge, a crowdfunding campaign ("I make Rotterdam") was launched: with 25 euros everybody could buy a plank with his own name engraved on it. Luchtsingel was assembled with more than 8.000 planks, throughout six building phases, from 2012 until 2014 (ZUS, 2012). With the canonical development strategies many years would be needed to trigger the change: in this case, choosing crowdfunding as the tool for bringing back urban qualities, giving the citizens the opportunity to develop small scale and low budget interventions with agile procedures, meant offering a successful alternative to traditional planning, no more suitable to the current market conditions.
In 2012 the project won the Rotterdam City Initiative with the 48% votes of the citizens called for choosing a series of projects running the competition, and was awarded with 4 millions euros for its realization. The award contributed to the implementation of the other goals of Test Site Rotterdam: the creation of new public spaces around the bridge, which was ended in 2015, and the consequent start of a number of activities in the area.
Luchtsingel indeed organizes three different places in Central District, encouraging their rediscovery and use, creating new paths not feasible before. The first landing place of the bridge is Schieblock, the office building owned by the City of Rotterdam, abandoned for many years. ZUS with the municipality and a local developer opened here a temporary "laboratory for urban development", where creative entrepreneurs can find spaces and conditions useful to develop their plans. Divided in private studios and semi-public spaces, Schieblock has opened its ground level filling it with public activities, encouraging the interaction between the city and the building: bars, restaurants, shops. On the roof, a collective vegetable garden (Het Schieblock, n.d.). They are all temporary activities: using temporality allows triggering different activities with sustainable economic investments, as well as testing (and eventually adapting) methodologies and actions during a given period of use. In some cases, temporality becomes a "long term temporality", almost permanent: uses take root in spaces, and the socio-economic fabric gets thicker.
In other words, ZUS's intervention in the Central District embraces the placemaking model, a shared approach to the design of public spaces targeting the regeneration of districts and cities. In this case, an ephemeral infrastructure such as a wooden bridge becomes the device which fosters the relationship between citizens and the places they share, exploiting the collaborative process between public and private actors, in every step of the process. One can define it as a creative model of use, that is particularly careful to management after design and construction, and presents a great benefit in terms of costs.
Besides the Schieblock, the construction of Luchtsingel involves the acceleration of the redevelopment of the railway viaduct Hofplein nearby, recently refurbished, under whose arches stand ateliers, shops, cafés. The yellow wooden bridge lands on its roof, bringing people to the cultural events that take place here (van der Kleij, G. et al., n.d.).
The third intervention area is the space crossed by Luchtsingel at high altitude, Pompenburg, once a storage area situated between busy roads and the railway. The project transformed this place in a green park, which provides space for recreation and urban agriculture, such as a lawn, sports courts and barbecue areas. The park is the pivoting point within a larger network of public green.

Gap Filler. Designer as a social mediator
Temporality means thinking about many beginnings, but also about a number of endings: how to manage the conclusion of an activity within the city in positive terms? This is not a dimension to whom the planning practice is used to. The recurring risk is to let many pieces be added to what has already been abandoned.
From this standpoint, a positive example -although it is about a different temporality from the one experimented in Rotterdam -is the experience led by Gap Filler in Christchurch, New Zeland (Bennet, Halliday, 2014). In 2010 and 2011 the city was struck by a tremendous earthquake, and a large part of its buildings was demolished. In 2011 one of the first answers to the urgent quest of public space in a town full of gaps was Pallet Pavilion, a project for a new collective space presented by Gap Filler, a group created by researchers and professionals from different disciplines in order to bring life to the city promoting and coordinating public initiatives in the countless voids left in the urban fabric. The space selected for such an experience was the block once occupied by the Crown Plaza Hotel, whose land was owned by the council and leased to the hotel company. Gap Filler got permission from the lease holders and the owner to use the land for free. Planned by young designers supported by established professionals and built in 2012 in six months entirely by volunteers, the temporary architecture work of Pallet Pavilion was composed of 3.000 wooden blue pallets assembled on large concrete slabs coming from demolitions. Pallets were sponsored, as well as electrical and steel. In summer 2012 this new space housed 25.000 people attending more than 70 events. The pavilion was intended to be deconstructed in May 2013, but the people's question for preserving it was such massive that Gap Filler was persuaded to open a crowdfunding campaign in order to renew its activities for another year. The initiative got a major success. The Pallet Pavilion was disassembled in May 2014.
Again, thanks to the designer's networking and fundraising capability, this experience brought positive outcomes on urban spaces, fostering the construction of a transformation model where the designer himself is the promoter of economic, social and urban regeneration, and at the same time, a mediator among the different interests of the many players on the scene.

The critical-application role of experimental teaching process
The research, understanding and experimentation of new architectural practices where "the social mobilization has to meet the capacity of the institutions to make space to the social innovation" (Pasqui, 2014, p. 8), are essential to set up innovative design approaches, useful to face the problems that the existing built offers to the new generations.
These "alternative" practices have to recover their experimental basis in the teaching experience, presenting the critical role of education as an important tool to develop a different design sensitivity. The University therefore must act as a favorite place of reference and comparison at every level of competence: teaching, experimental, research.
Especially, the work on disused existing built at an urban scale, has interesting opportunities to develop synergies between architectural renovation and alternative models for their management and reintegration in the cycle of activities of the urban community.
"The empty spaces can be intended as urban reserves for the experimentation of collective dreams. For a while they are spaces resistant to economic pressures, free to receive and leave to settle a social capital". (I. Inti, G. Cantaluppi, M. Persichino, 2014, p. 128) 4.1 LABZONE2: urban regeneration experiments "Architecture, by definition, is an agent in the process of manipulation and transformation of goods (whether private, public or common) but it also participates increasingly in the process of affirmation of values such as identity, awareness, appropriation: values involved in any process of construction (and management) of space and goods, and all the more so when they take on the character of the common good. (…) the process itself constitutes a common good, capable of generating new knowledge, a sharing of resources, the spread of democracy and greater comity". (TAMassociati, 2016. p. 30) In this spirit the experience of LABZONE2 (Politecnico di Milano, School of Architecture, Urban Planning, Construction Engineering) was carried out. It is a multidisciplinary research project for the development of urban regeneration proposals for disused buildings, based on social innovation strategies oriented to cultural policies of inclusion. These proposals aim at the development of innovative ideas to create multifunctional urban spaces for social and productive aggregation, with easy economical access and with promotion of historical, cultural and environmental contents.
The projects, developed within the laboratories of the Master of Science are focused on the Municipality 2 in Milan: a large area of the North-West with a complex spatial nature and a great social and cultural mixture. In fact, here there is the highest multi-ethnic concentration of the city and a surprising vitality of citizens' associations.

LABZONE2 declaration
LABZONE2 takes the mission of diversity as primary resource: territorial, social, cultural, political and productive. It becomes a focus point in the transformation process of the area. The goal is to develop alternative examples of local governance, according to bottom up strategies, by configuring reactivation models of disused buildings, aimed to involve and support disadvantaged people (in particular immigrant communities, elderly people and economically less protected persons). The different projects will provide together a territorial network of reference and they will be based on functional mix: in fact, each intervention want to trigger collective functions based on social innovation principles, able to generate new attractiveness of the area, strengthening its role within the entire urban context.
This design strategy uses these tools: -Analytical mapping of the resources of the territorial system (paths system, urban system, open spaces, elements of cultural interest, dynamics of use and colonization of the space, etc.), highlighting constraints and opportunities; -Development of social models for the re-use of the buildings, integrating social orientation services, support to start up for handicraft and production activities and spaces for cultural and artistic exchange; -Development of participative methods for defining models with the direct involvement of social realities, associations and local government.
The main goal of LABZONE2 is the establishment of municipal spaces, into buildings already existing and recognizable as meeting and social cohesion places, able to set new mode of perception and use of public structures. In these spaces, the usual activities "at desk" of the municipal offices are redesigned through the interaction with new functions such as small new generation libraries (with book sharing vocation), aggregation spaces for social and cultural initiatives (recognition and exchange among the different ethnic components of the area), spaces for leisure facilities (art workshop and self-managed activities), rotating space for welfare activities (non -profit organization, associations), spaces for vocational training of first employment (even with self-managed multiethnic forms), study rooms, conference hall, exhibition spaces and places for temporary commercial activities (bike shops, home assistance, etc.). The outlined strategies will have to act as a force for the consolidation of the inclusive cultural policies as standard practice with the involvement of the most representative institutions, by activating innovative participation, productive and cultural forms.

Conclusion
Quoting Françoise Astorg Bollack "the architectural problem can be defined as the problem of the relationship of the old to the new and the way to manage this relationship is being worked out, not based on imitation, composition or modularity, but by working out idea of separation, integration and the idea of designing with history" (Astorg Bollack, 2013. p. 21).
But, it's necessary to add, the contemporary design for the existing built must face the comparison between past and present, also by restoring its natural multidisciplinary vocation, with a renewed sensitivity to the social, political and economic trends to propose regeneration models (of the buildings, of their use and of the context) able to reactivate the entire urban context.
As observed by Liliane Wong with a sensible musical metaphor "in modern-day performance, the second violin describes a group of 14 to 16 musician that make up the strings section of an orchestra. As musicians, second violins are equally skilled as first violin but play separate and different parts of the score. The first violins play the melody and the second violins play to support the melody through harmonic and rhythmic parts. (…) The practice of adaptive reuse is much like playing the second violin to the melody of the host building. It is a song of redaction in which the minor keys humbly and sweetly negotiate between existing context and new content" (Wong, 2017 p. 245-246) The regeneration process must arise by reviewing the current design practice which often looks to the territory as a mass consumer item and that considers the architecture able to innovate only through great interventions [Borsotti, Campanella, 2013]. It is instead necessary to work with "small mending operations, minor building sites and transplants to be carried out with the participation of the inhabitants of the neighborhood". (Piano, 2016. p. 9)