Modernising and modifying an existing building: a paradigm for sustainability in construction
The city’s new center of gravity is a converted department store that now also is a multifunc-tional lecture center. This saves resources (sustainability), brings together diverse population groups (inclusion) and revives the city center (quality of experience).
A small major city that has been shaped by its industry is reinventing itself. That is only possible be-cause the municipality and university cooperate tightly in order to shape a new future.
Regional
Germany
Landesregierung Nordrhein-Westfalen, City of Siegen, Kreis Siegen-Wittgenstein.
It addresses urban-rural linkages
It refers to a physical transformation of the built environment (hard investment)
No
No
Yes
2020-10-01
As a representative of an organisation
Name of the organisation(s): University of Siegen Type of organisation: University or another research institution First name of representative: Matthias Last name of representative: Meinecke Gender: Male Nationality: Germany Function: Assistant to vice-rector for resources and governance Address (country of permanent residence for individuals or address of the organisation)<br/>Street and number: Unteres Schloß 3 Town: Siegen Postal code: 57072 Country: Germany Direct Tel:+49 271 7402182 E-mail:matthias.meinecke@uni-siegen.de
10 years ago, an opportunity arose for relocating three faculties when real estate at the city center was available: the castle “Unteres Schloss” and the former municipal hospital. These buildings were renovated from the very foundation, converted and modernized with regard to their new function.
None of the renewed buildings available could offer the requirements for a modern lecture center. A 1970s-style department store is located vis-à-vis the castle. Owing to the development in retail, it faced the thread of closure repeatedly which would have been a severe threat for the development of the upper town. The idea emerged to convert the topmost floor of the building into a modern lecture center and was finally turned into reality. But first, solutions had to be developed: integrate a lecture theater with upward-sloped seating, design a new façade, and implement these in the running department store.
The project follows the vision of multiple circularities in 10 aspects:
1. Renovation of existing building fabric for re-use (circular constructing).
2. Prevention of new construction by cooperative use of area reserves (circular area recycling).
3. Flexible use of buildings (circular urban mining design)
4. Replacement of pollutant materials with pollutant-free/low-pollutant materials (circular downcycling).
5. Development of a socially separated university infrastructure into a city-integrated university infrastructure (circular upcycling).
6. Integration between modern university and urban development (circular local sustainability).
7. Directing purchasing power into local retail (circular prosperity).
8. Creation of knowledge- and culture-based rooms for potentials (circular creativity).
9. Manifestation of urban talent pools (circular innovativeness).
10. Intensive involvement of all participants and stakeholders (circular governance).
All these aspects support the urban resilience as well as the mobilization of a modern university.
Refusbishment
City Center Renewal
Participation
Encounter
City Society
The project is part of the project "Siegen. Knowledge unites" and focuses on two fundamental problems of sustainability: the re-use of real es-tate and the reshaping of quarters in transformation.
The narrow goal is the re-design of a former department store while integrating the existing building fabric. The modernization does not only improve the energy balance of the building, but rather the resource balance as there is less use of building material and area. Restructuring this very building from 1971 means restructuring one from the grey inventory that never had to meet any goals of heat insula-tion or energy efficiency. A new life cycle started for the building that was initially not anticipated.
By adding a floor on the top and renewing the façade of what’s now the lecture center, it was possible to raise the energy standards to modern levels of building insulation. The building now meets high efficiency standards: the ventilation system uses CO2 sensors to identify the demand which saves energy, while LED technique saves up to 75% compared to conventional lighting. Since the building has just been completed in autumn of 2020, in the middle of a pandemic, it has seen little use and it is hard to testify about its energy savings.
The second - wider - goal manifests in urban planning. City centers lose their attraction: department stores break away in anchoring customers for retail and the pandemic exacerbated this situation. Moving three faculties to the city center, the university creates attractive, vivid and sustainable quarters that function as anchor for retail and open public spaces for recreation and discourse.
The lecture center is nucleus and hinge-joint for a city center university: it links campus of three faculties and opens up the university to a wider public. Compact, multi-role quarters are created that sus-tainably reduce traffic, in addition to short-distance routes and new mobility concepts for the city center.
The layout of the existing building’s entries was completely misplaced for the new purpose of a lecture center. Opening up to the “Schlossplatz” (castle square) was necessary due to the students moving schemes. Thus, the buildings former backside had to stand up as face façade vis-à-vis the castle. The strictly ordered façade of the late-baroque castle meets a qualitative equivalence in the clearly structured concrete supporting façade which picks up the historical principle of order but translates it into a contemporary shape scheme. Exposed concrete was chosen for material in order to adopt the texture of the other three façades and to complete it.
The interior’s development of the upper floor was turned to the castle square and emphasized by a broad foyer, which in combination with the façade creates a convincing entry space in front of the lecture halls. The triple-run stair complex with free space, ca. 9m wide und with big skylights, develops the upper floor from the castle square. The supporting structure of the concrete rib deck had been uncovered during interior works. It essentially determines the room’s character and exemplifies a part of the constructing history and cultural history of the 1970s and its concept of time. The heart of the new complex is a lecture theater with 600 seats. Skylights supply daylight to the rooms and the wide-span steel beams refer to the steel processing history of Siegerland.
The building also stands pars pro toto for a concept that accompanies the university’s planning approach: it opens up spaces to a public beyond university members and increases staying quality in the city center as a whole. Thus, a third space is created, where different kinds of people encounter and meet to form one city society.
By combining an existing department store with a lecture center, the project is quite a unique fusion. It opens up the university to a broader public in a one-of-a-kind way because of its integration into an existing city structure, the cooperative use and its transparency
From a perspective of urban planning, the building is going to unfold an integrative impact: while the closure of other department stores in the upper city of Siegen erased important frequency anchors for the center, the new lecture center will keep the flow of people in the city, thus countering a devaluation of this important public space.
In the future course of project Siegen. Knowledge unites there will be a creation of more high-quality semi-public areas to retreat for university members and entirely public areas for recreation for anybody: Siegen citizens wander through their town and through the university simultaneously.
Three newly arranged quarters will also unfold an interior integrative effect: each quarter is arranged as an organic location of a specific faculty which is going to a scientific unity as well as opening up to the remaining university as a single unit. Furthermore, the faculties open up to the city’s public and will grow to an essential part of their respective quarter.
Accessibility is an important part of the project. People with limitations can explore the building com-pletely independent. A lift links the entrance level with the upper floor. Wherever the weight of doors places an obstacle, electric operated doors will open. Induction loops and additional technical equipment were integrated in the lecture theater in order to improve voice transmission. A newly standardized tactile pathing system has been introduced with the seminar center and will be placed in all subsequent buildings (cafeteria etc.).
The establishment of the lecture center and the campus means the creation of new frequency anchors in the upper town and a development perspective for this urban interaction space. The innovative concept for the additional floor on top of the department store will also be open to a number of public functions. It offers gregariousness and encourages diverse groups to frequent social interaction, in-creases the society’s social capital, fosters cohesion in the quarters and increases life quality in total. Amongst other things these rooms will be open to citizen science approaches.
Here a meeting place was opened: citizens and students traverse through the department store, pass the lecture center and step onto the central square of the city, the castle square, were they experi-ence art exhibitions, concerts, Christmas markets or public viewing of soccer together.
Diverse authorities are integrated into the process and committed. The working group “cityscape of-fense” was formed in 2011 for a regular exchange about questions of climate protection, city ecology and cityscape between authorities and citizens, and this has been intensified for the project Siegen. Knowledge unites. The public opening for the wider discourse started 2019 in the Apollo theater, in October 2020 the winner of the urban planning contest was presented to the public at the same place and in the summer of 2021, several city walks and other information opportunities – now many online – were initiated.
In June 2021, the masterplan of the complete project will be presented to the public. A fruitful and active interpose, especially with citizens, is installed between all these steps in order to discuss what matters to stakeholders. This discourse on traffic, integration of quarters and cityscape created impulses that found entry into further development plans. The current status of the project and ways for entries are continuously communicated on the project page www. siegen-wissen-verbindet.de
At the local level, first the City of Siegen and the University of Siegen were involved in the project as primary drivers.
The city was well aware of the tensions in the city center that have arisen by the opning of the shopping center at the train station and the negative effect of e-commerce on shops, while the university had to deal with the problem of having a multitude of locations to maintain and service. They were the first movers in this project and coordinated closely. The university and the city formed a common task force and named contact persons to service the project.
With this first coordination setup, the university approached the state of North Rhine-Westphalia (regional/national) to evaluate room for manoeuvre, especially financially and to lay paths for procedures. The coordination between city, university and state was crucial as this is a long and complex planning process.
When this milestone was reached, two other local stakeholders were included in the planning process: the Karstad company and citizens. Karstadt proposed a scheme for re-configurating it's department store and keeping it running while simultaneously renovating.
And last but not least the citizens of the city were invited to participate at the various stages of the project. Since the lecture center is only the starting point of macro project of moving the university into the city, this participation is still running and evolved from mere sessions to inform cirizens to collaborative formats and a 24-hour channel via the projects website.
The different stakeholders constantly made inputs that found their way into the project interatively, up to this date, since other projects of the relocation are on their way.
The University of Siegen added it's unique knowledge in the administration of a vast institution and the comlex realm of Germany's university sector. This includes business aspects of running the institution as well as bringing together distinct institutions and stakeholders. The process of aqcuiring only the land slots for this project was itself a complex problem that needed a lot of combined effort of the university and the city.
The City of Siegen added distinct value in the fields of city and especially traffic planning. Since the university relocates primarily from the outskirts to the city, a huge change in guiding traffic streams and in traffic itself is needed. Furthermore, the city brought in it's knowledge of the complex matter of building law and priotised the needs of this project.
The architect's office helped solving two critical issues: first, offering a aesthetically pleasing proposal that integrates into the Schlossplatz (castle square), while solving the technical problems of opening up and re-building the building's structure while the shop was running. Now, as the project enters the second phase, i.e. forming two new campus areas, the university's archtecture students are getting involved in various planning stages for the project. Thus, the university makes itself a project of consideration.
The establishment of the lecture center and the campus means the creation of new frequency anchors in the upper town and a development perspective for this urban interaction space. The innovative con-cept for the additional floor on top of the department store will also be open to a number of public functions. It offers gregariousness and encourages diverse groups to frequent social interaction, in-creases the society’s social capital, fosters cohesion in the quarters and increases life quality in total. Amongst other things these rooms will be open to citizen science approaches.
Here a meeting place was opened: citizens and students traverse through the department store, pass the lecture center and step onto the central square of the city, the castle square, were they experience art exhibitions, concerts, Christmas markets or public viewing of soccer together.
Diverse authorities are integrated into the process and committed. The working group “cityscape offense” was formed in 2011 for a regular exchange about questions of climate protection, city ecology and cityscape between authorities and citizens, and this has been intensified for the ongoing project Siegen. Knowledge unites. The public opening for the wider discourse started 2019 in the Apollo theater, in October 2020 the winner of the urban planning contest was presented to the public at the same place and in the summer of 2021, several city walks and other information opportunities – now many online – were initiated.
In June 2021, the masterplan of the complete project will be presented to the public. A fruitful and active interpose, especially with citizens,is installed between all these steps in order to discuss what matters to stakeholders. So far the discourse on traffic, integration of quarters and cityscape created impulses that found entry into further development plans. The status of the project and ways for entries are continuously communicated on the project page www. siegen-wissen-verbindet.de
The combination of a department store and a lecutre center is dedicated to heterogeneity because it brings together university and city society in Siegen’s upper town. The concept for the building is actu-ally innovative and far surpasses common approaches like in-house shops. Consequently, the location Siegen was struck off Karstadt’s renovation-based shutdown list where it was located ever since the company’s troubles.
The diverse activities in the building initiate exchange and open up entries to other social subsystems: here the classical department store clients, there members of the university. The seminar center has the function of a third place that is internally and externally inclusive, creates a connection to the cen-tral place of city society, the castle square, and offers a high attraction to heterogenous groups of peo-ple. A great number of people uses the structure out of different, pre-structured reasons, and en-counters the unfamiliar.
From an engineering perspective, large efforts have been made to revitalize existing building fabric and to connect this to new concepts. While the department store was still open, the escalators had to be dismantled and the main girders of Pi panels were sawn and lifted on the spot while hanging from a crane. The roof was removed and the building was increased with an upward-sloped floor in order to meet the height requirements of the lecture theater with rising stalls and the necessary technical centers.
Since parts of the building reach two stories below the castle square, it was also necessary to hang up the new façade facing the castle square and to direct weight into the existing construction. The entire building services of the department store and university were separated.
The far-reaching renovation with interventions in the structure of the building was a challenge, as the existing grandfathering concerning fire protection ceased. The building had to be upgraded to satisfy current requirements in fire
While sustainability aspects in construction often relate to building new and highly efficient buildings, the approach for the lecture center tries to revive existing buildings. While this building cannot come up to the newest standards, this approach helps saving a lot resources as constructing and especially concrete have a lot influence on climate change. Furthermore, removing a building that is not designed for resource circularity results in a special waste that can seldom be recycled. Having brought this approach to some maturity, it will be used for futher stages of he macro project "Siegen. Wissen verbindet" which the lecture center is part of.
While it is extremily demanding to reach sustainability goals for the European Union with the capacities of new construction, re-construction is one way to go and save resources. Furthermore, this can help a lot of towns in utilizing empty buildings that are difficult to convert.
Thus, the Karstadt building is now also a modern lecture hall in the middle of the town. This helped the university, that faced problems with having various locations. This helps the city, which does not have to deal with empty buildings and an empty city center. This helps the citizens that can enjoy a quperios quality in city centers. And it helps the environment as a lot of resources are saved. And it may work as an example for other towns.
The project focuses the important question how to keep resources invested a long time ago into con-struction can be kept within the resource cycle. The intention of this holistic approach is to minimize the resource balance sheet of the building. Emissions of CO2 mainly take places in building stock. 60% of this stock has been build before 1979 and does not meet any requirements for heat protection, freedom from structural physical damage or energy efficiency. Thoughtful concepts for re-use of build-ings can transform this grey building stock into an asset.
A very specific re-use concept is implemented for a building whose unmodified re-use would be diffi-cult. Regarding the development of department stores in particular and retail stores in general, there are hundreds of properties located downtown that need a proper concept for re-use and without, they are merely a burden for city centers. The University of Siegen generated experience with similar properties, e.g. a former municipal hospital or the castle, that beforehand hosted an incoherent ag-glomeration of different public services, ranging from a prison to city building authorities. Additional projects like the former department store Hettlage are on the way.
Furthermore, city and university offer solutions for interlinked quarters beyond the scope of a building: concepts that start with plan for a single building, its integration to the quarter and the quarter’s inte-gration to the city. And these concepts are linked to a new traffic concept that seeks to
Intercept car flows at the periphery and transforms large areas of the center into pedestrian and bicy-cle areas. In the course of the project Siegen. Knowledge unites sustainable solutions are created that are showcased at the this very building.
Department stores used to be a special attraction for purchasing power: they established themselves as customer magnets in the centers of decentralized and suburbanized towns and vitalized the down-town areas, while exerting attraction to the further retail. This very principle used to work until the 1980s.
Downtown Siegen also went by this logic: the former department store Tietz is located at the upper end of the upper town’s principal shopping mile, Kölner Str., while Karstadt is located at the lower end, all surrounded by retail stores. Siegen’s role as a regional metropolis guaranteed the inflow of custom-ers and the shopping mile between the department stores generated rents common to locations like Düsseldorf. The aura further diminished with the opening of a shopping mall in the lower town in 1998.
The increasing proportion of e-commerce and if nothing else but Corona put up to discussion the exist-ence of various department stores with effects for retail and city centers. The Corona crisis is working like a burning glass: 30% of retail areas are considered superfluous with all dire consequences for city centers and the thread of devitalization.
115 department stores were closed in Germany from 2004 to 2019, many in city centers. While their further utilization demonstrates itself a complex task, few of them meet modern energy standards. Furthermore, the existence of the remaining 175 department stores will be subject to discussions. From a resource perspective, a suitable re-use of an abuilding fabric is more rational than a demolition since a re-use of demolished construction material is regularly impossible.
Siegen is a real-time laboratory for the urban transformation process of middle-sized cities: the urgent problems of city center obliteration and the revitalization of old building fabric are approached proactively. A second life equals resource efficiency: buildings can be included into a resource cycle without initially being designed to.
