The Role of Third Spaces in Addressing Urban Decline: A Schweinfurt Case Study

Highlights

Please indicate how your work links to systems science via your contributions to systems practice, theory, and/or methodology.

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This work evaluates third spaces as systemic urban interventions that integrate social, educational, and economic functions to counteract inner-city structural decline, extending systems theory on multifunctional social-innovation hubs.

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It also applies a mixed-method systems approach, with longitudinal pedestrian-sensor data, the PHINEO impact framework, and PSI metrics. Which is benchmarked against two structurally different urban-innovation systems (Utopiastadt, CityLAB Berlin) to reveal scale-dependent transferability and complementary system logics.

What are the main findings and/or the implications of the main findings?

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This work demonstrates that while StudyFAB did not significantly shift macro-level pedestrian traffic on Schweinfurt’s market square, it produced strong, statistically significant positive shifts in user behavior, city-centre perception, and local economic engagement within its target group (Spearman’s ρ up to 0.68).

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It also positions third spaces as scalable, resource-efficient, and complementary building blocks for sustainable urban transformation in medium-sized cities. It ismost effective when paired with structural or governance-level measures rather than used as a stand-alone solution.

Abstract

This study examines StudyFAB in Schweinfurt, Germany, as a case of inner-city revitalization through a comparative analysis of third space initiatives. In response to declining pedestrian traffic and rising vacancies linked to online shopping, it investigates StudyFAB’s impact on foot traffic, perceived quality of stay, and user engagement, compared with Utopiastadt Wuppertal and CityLAB Berlin. Using a mixed-methods design, the study combines pedestrian counts, PHINEO impact metrics, usage data, and a survey of N = 93 participants (33 StudyFAB users, 30 aware non-users, and 30 non-users). The findings show that StudyFAB did not significantly increase overall city-wide pedestrian frequency, but statistical analysis indicates strong positive associations and behavioural tendencies within its target groups, including more frequent city centre visits, improved perceptions of the city image, high user satisfaction, and measurable participation. Compared with the broader neighborhood and governance approaches of Utopiastadt and CityLAB, StudyFAB demonstrates a focused but effective contribution to urban revitalization. The results suggest that third spaces can serve as complementary tools for urban transformation when social, cultural, educational, and commercial functions are integrated. Future research should examine long-term scalability, sustainable funding, and transfer effects across projects.

1. Introduction

Urban centres are essential hubs for society, driving economic activity, fostering cultural exchange, and facilitating community interaction [1]. However, contemporary urban landscapes are increasingly challenged by shifting consumer behaviours, most notably the surge in online retail, which has resulted in diminished pedestrian traffic and rising vacancy rates within city centres [2,3,4,5]. This evolving dynamic necessitates the development and implementation of innovative strategies aimed at revitalizing urban cores and enhancing the overall quality of stay for residents and visitors alike. This is especially important for smaller cities like Schweinfurt (approx. 54,000 inhabitants), as metropolitan areas with established omni-channel retail strategies have been shown to be more resilient to online competition [5]. This requires strategies that meet the needs of visitors: a clean, green city with a high quality of stay and places to interact [6,7,8] and a city for entertainment, not just shopping [9,10].

Schweinfurt, like many German cities, is grappling with significant urban challenges, including increasing retail vacancies, declining pedestrian traffic, and dissatisfaction among residents with the quality of its inner-city spaces. These issues are primarily driven by structural changes in consumer behaviour, such as the rise of online shopping, which has reduced footfall in traditional retail areas [11]. The city’s marketplace, once a hub of activity, now struggles with underutilization and a lack of vibrancy. Residents express a desire for more engaging and multifunctional spaces that foster community interaction and improve the overall urban experience [1]. This situation is compounded by Schweinfurt’s broader demographic and economic trends. The city is experiencing a “downward curve” characterized by population aging, limited economic diversification, and urban stagnation. Without intervention, these trends threaten to exacerbate urban decline, making revitalization efforts increasingly urgent [12,13,14].

Despite the pressing nature of these challenges, there is a notable gap in research on effective solutions. Social innovations like third spaces—public or semi-public areas designed to encourage social interaction—are gaining attention as potential tools for revitalization. However, their impact remains unexplored in the academic literature. Few studies rigorously evaluate their effectiveness in addressing urban vacancies or improving quality of stay or life.

The StudyFAB project in Schweinfurt provides a unique opportunity to address this gap. As an example of a third space initiative, it offers insights into how social innovation can contribute to urban renewal. By measuring its impact on pedestrian frequency and perceived quality of stay, this study aims to provide actionable evidence for policymakers and urban planners seeking sustainable solutions to revitalize declining city centres. Within academic discourse, there is growing recognition of the potential of social innovations as a means of addressing the complex challenges facing urban areas [15].

A particularly promising concept is the third space, which is neither home (first space) nor work (second space), but which serves as a communal gathering point that encourages and facilitates social interaction [16]. These spaces are believed to foster stronger community bonds, improve the overall urban experience, and contribute to the rejuvenation of city centres [16,17].

This study focuses on a case study of a third space operating as a social innovation, StudyFAB in Schweinfurt, Germany. StudyFAB is a publicly accessible space designed to provide a flexible workspace, meeting area, and community hub for students, entrepreneurs, travellers, and residents. It aims to address the challenges of vacancy and urban decline in Schweinfurt’s city centre by creating a welcoming and engaging space that attracts all people of all ages and genders to the area. The primary objective of this study is to evaluate the effectiveness of StudyFAB as a tool for urban revitalization, addressing the following key research questions:

• Does the presence of StudyFAB correlate with changes in pedestrian frequency in Schweinfurt’s market square?
• Is the use of StudyFAB associated with a more positive perceived quality of stay in the downtown area?

Building on these two research questions, this study tests three hypotheses. Linked to RQ1, H1 is proposed as follows:

H1. 

The presence of StudyFAB is associated with an increase in pedestrian frequency at Schweinfurt’s market square.

Linked to RQ2, H2a is proposed as follows:

H2a. 

The perceived quality of stay at Schweinfurt’s market square is higher among individuals who actively use StudyFAb than among non-users.

H2b is proposed as follows:

H2b. 

The perceived quality is likewise higher among individuals who are aware of StudyFAB and could use it than among non-users.

2. Literature Review

The phenomenon of inner-city decline has been extensively studied in urban planning. Authors like Henckel et al. (2007) [4] describe how increasing vacancy rates can trigger a “trading down” effect, leading to a downward spiral of decline. This effect manifests in less foot traffic, closures of small businesses and retailers and a general reduction in the quality of the urban environment [18]. Studies also highlight the impact of e-commerce on traditional retail, leading to decreased foot traffic in brick-and-mortar stores [3].

The third space concept, popularized by Oldenburg (1989) [16], provides a theoretical framework for understanding the role of informal public spaces in fostering social interaction and community building. Oldenburg argues that third spaces are essential for creating a sense of place and belonging in modern society. They provide opportunities for people to connect with one another, share ideas, and build relationships [16]. Third spaces can also serve as incubators for social innovation, providing a platform for community members to experiment with innovative ideas and solutions to local challenges [19,20]. Examples of social innovation in Germany include the creation of co-working spaces, urban gardens, and community-supported agriculture initiatives. These projects are often driven by grassroots organizations and aim to address local needs and challenges in innovative ways [21].

Recent developments in working patterns have further expanded the relevance of third spaces. Since the COVID-19 pandemic, hybrid and remote work have become more established as a lasting mode of organizing work rather than a temporary exception, with implications for mobility, office presence, and everyday urban routines [22]. Recent research suggests that hybrid work also affects team cohesion and organizational routines [23], while co-working spaces and other “third working places” gain importance as flexible environments for work, social interaction, and informal exchange [24]. At the same time, post-pandemic debates on city centres increasingly emphasize multifunctionality, accessibility, and the ability of urban spaces to support work, encounter, leisure, and everyday services beyond retail alone [25]. For this reason, third spaces such as StudyFAB should be understood not only as places of social encounter, but also as part of a broader post-COVID-19 urban infrastructure that responds to changing work and city centre use patterns.

Empirical studies on third spaces demonstrate their effectiveness in promoting social interaction and neighborhood revitalization, particularly through the interim use of vacant buildings as hybrid usage spaces [26,27]. Comparable initiatives like Utopiastadt Wuppertal and CityLAB Berlin illustrate how third spaces enable participatory urban development and innovation (see Section 3).

The quality of stay refers to the overall attractiveness and comfort of an urban environment. Factors influencing the quality of stay include the availability of public spaces, the presence of green areas, the safety and cleanliness of the environment, and the diversity of cultural and commercial offerings [10,16,28,29,30,31,32]. Gehl (2011) [29] identified twelve design criteria for enhancing urban spaces. Research suggests that improving the quality of stay of inner cities can help to attract visitors, boost economic activity, and enhance the overall well-being of residents [17,29,33,34].

The literature on social innovation highlights the potential of community-led initiatives to address complex social and economic challenges [15]. Social innovation is defined as “a new, sustainable and effective solution to address societal social problems and improve living standards” [35]. In the context of urban revitalization, social innovation can involve creating new forms of public space, developing innovative business models, or fostering community engagement through participatory and inclusive processes [35,36,37,38].

3. Research Method

The conducted study is based on a mixed-methods approach. The research design encompassed a combination of quantitative and qualitative methods to explore data from various sources. A digital interview was developed as a research design to capture the opinions of non-professional users of the Schweinfurt marketplace and StudyFAB. The questionnaire adopts a between-subject design in which the level of awareness of StudyFAB is surveyed to create three groups. Group one serves as a control group and comprises people who do not know and do not use StudyFAB. Group two is made up of people who are aware of StudyFAB and its services but have not yet used them, and group three is made up of those who have used StudyFAB at least once. These subdivisions function as independent variables (IVs). The dependent variable (DV) is the quality of stay and the evaluation of Schweinfurt city centre [39].

3.1. Frequency Measurement

Pedestrian frequency was measured using automated counting devices installed in Schweinfurt’s market square. Data were collected over a period of six years (2018–2024) to analyse trends. StudyFAB opened on 21 July 2023, but this study focuses on October 2023 to February 2024 to reflect regular operations after staffing adjustments. This period is then compared to data from Schweinfurt’s marketplace from 2018 to 2024.

3.2. Method of Impact Assessment

The impact of StudyFAB was evaluated using the PHINEO impact staircase (see Figure 1) developed by the German social organization PHINEO; it is a method for analysing the impact of social projects. According to this method, social impact occurs when measures lead to changes in the target group, their environment, and society. These changes are categorized into outputs, outcomes, and impact. Figure 1 illustrates the seven stages that these changes go through and their alignment with the project’s Key Performance Indicators (KPIs) [40].

The output forms the basis for the impact and is defined by providing planned activities in which the target group is reached and the offer is accepted (stages 1 to 3). Stage four is when the impact starts because the outcome begins, and behaviour is measurable. In the first part of the outcome section, there is a change in the awareness or abilities of the target group, while the action changes in stage five. Stage six is reached when the target group’s living situation changes. The last stage, the impact, no longer refers to the target group alone but rather a societal effect [40]. The framework was applied to StudyFAB, matching KPIs, and used tracking data, questionnaire results, and pedestrian data to evaluate each stage, uniting research methods.

3.3. Questionnaire

A questionnaire was developed to gather data on the perceptions of the downtown area, the usage of StudyFAB, and demographic information. The questionnaire included both closed-ended and open-ended questions to provide quantitative and qualitative insights. The questionnaire was designed based on the variables and was translated into German. Most questions were closed-ended to increase objectivity in implementation and evaluation [39]. Individual attitudes were captured using four- and five-point Likert scales. Open-ended questions were also asked to gather individual opinions beyond the information provided. The questionnaire was used to evaluate the remaining goals of the impact staircase and assesses the hypotheses.

The first section focuses on the potential of StudyFAB. In terms of content, it looks at how the premises are used over time and which elements are important. In addition, the study is examining the extent to which the use of StudyFAB influences users’ opinions and behaviour with regard to Schweinfurt city centre. Three open questions allow participants to provide free feedback and suggestions for improvement. The section is rounded off with an evaluation of StudyFAB in the form of school grades and the Net Promoter Score (NPS). The NPS provides information on the extent to which respondents would recommend the company’s services to friends.

The second area surveyed the quality of stay at Schweinfurt’s market square in the city centre, including the surrounding buildings and amenities. Measurement of the quality of stay can be done in different ways, such as observations, checklists, workshops, and surveys [41]. The Public Space Index (PSI) [42] was selected because it enables a holistic view, has a weighting per item, and has already been used multiple times in studies [41,43]. The questionnaire is divided into five dimensions: Inclusiveness, Meaningful Activities, Comfort, Safety, and Pleasurability. Each dimension includes seven to twelve items. The weighting of the individual items is different. The answer format is a four-level Likert scale, which awards zero to three points per item. In this study, the questionnaire was reduced to two questions per dimension. Following this section, the entire Schweinfurt city centre was rated on a German school grading scale from 1 to 6. The questionnaire was pretested with a small group of respondents to ensure its clarity and validity. Based on the pretest results, minor revisions were made to the questionnaire before its final application.

3.4. Sample Recruitment and Sample Description

To recruit participants for the questionnaire, the lead researcher approached passers-by at the Schweinfurt market square and within StudyFAB. After obtaining consent, participants completed the questionnaire independently on a provided notebook or via a QR code on their smartphone. The survey took 5–8 min and took place over 14 days, between 26 April and 10 May 2024.

The final sample included N = 93 individuals, with no exclusions due to data anomalies. The sample was divided into three groups: StudyFAB users (n = 33), those familiar with StudyFAB (n = 30), and non-users (n = 30). The sample included 60.2% female (n = 56), 38.7% male (n = 36), and 1% diverse (n = 1) participants, with a mean age of 37.25 years (SD = 17.24) and an age range of 12–83 years. Regarding employment, 17.2% were students, 12.9% were studying, 48.4% were employed, 9.68% were self-employed, 7.5% were retired, and 3.2% were unemployed. One participant was a legal trainee. See

Table 1. Demographic details of three survey groups (own illustration).

Characteristic	Users	Aware Non-Users	Non-Users
Gender
Female	63.6%	70%	46.7%
Male	36.4%	30%	50%
Diverse	0%	0%	3.3%
Average Age (Years)	28.18	45.03	39.43
Occupation
School Student	33.3%	6.7%	10%
University Student	18.2%	10%	10%
Employed	30.3%	53.3%	63%
Self-Employed	12.1%	13.3%	3.3%
Retired	3%	10%	10%
Not Employed	0%	6.7%	3.3%

for a complete demographic breakdown of each group.

4. Results

In the following section, we report only the empirical results of the StudyFAB case study; qualitative comparison with other third space initiatives (Utopiastadt Wuppertal, CityLAB Berlin) is presented separately in Section 6. The previously established hypotheses are statistically evaluated and the outcomes associated with StudyFAB are assessed using the PHINEO impact staircase, as shown in Figure 1. The calculations were conducted using the IBM SPSS Statistics Version 25 program. The hypotheses were assessed under the assumption of a normal distribution, as the three samples have a size of n > 30. Therefore, a one-factorial ANOVA was used in each case. The requirements of a metrically scaled variable and three independent samples are met in this experiment. Cohen’s d is used as the effect size measure and α = 0.05 as the significance level [44]. An effect size of d = 0.20 can be described as a small effect, d = 0.50 as a medium effect and d = 0.80 as a large effect.

4.1. Pedestrian Frequency

H1 states that the frequency of pedestrians will be increased by offering a modern third space such as StudyFAB. To verify the hypothesis, the frequency of passers-by from 2018 to 2024 was compared in the period from October to February. The pedestrian frequency data from 2020 to 2022 should be interpreted with caution, as these years were shaped by the COVID-19 pandemic and the subsequent recovery phase. Pandemic-related restrictions, altered mobility patterns, and changing urban activity levels may have affected footfall independently of StudyFAB’s presence.

Table 2. Frequency of pedestrians in Schweinfurt. Note: Only people carrying mobile phones were included (own illustration).

Winter Period (Oct.–Feb.)	Absolute Frequency	Median	Difference to Baseline (2023/2024)	Change Rate Relative to Baseline (2023/2024)
2018/2019	4,769,405	25,610	−512,791	−9.7%
2019/2020	5,891,426	30,811	+609,230	+11.5%
2020/2021 (COVID-19)	4,014,317	26,695	−1,267,879	−24.0%
2021/2022 (Recovery)	6,112,294	40,879	+830,098	+15.7%
2022/2023	8,816,067	46,060	+3,533,871	+66.9%
2023/2024 (Baseline)	5,282,196	29,695	0 (Reference)	Baseline

presents the descriptive metrics of pedestrian footfall during the winter periods (October to February) from 2018 to 2024. To contextualize the impact of StudyFAB (opened in July 2023), the winter season of 2023/2024 serves as the baseline for comparison. The metric “Difference to 2023/2024” represents the absolute variance in pedestrian counts between each historical winter period and the baseline period (calculated as $Historical\Count − Baseline\Count$). Correspondingly, the “Change Rate to 2023/2024” indicates the percentage increase or decrease of that historical period relative to the 2023/2024 baseline. A positive percentage signifies that the past year had higher footfall than the project period, whereas a negative percentage indicates lower historical footfall.

4.2. Perceived Quality of Stay

H2a and H2b proposed that the perceived quality of stay at Schweinfurt’s market square would be higher for individuals who use or could use a modern third space like StudyFAB.

The objective of stage five is to increase the number of visits to the city centre by the target group. A total of 39.4% of StudyFAB users take advantage of the offer several times a month and 39.4% even several times a week. Due to its central location on the market square, a visit to StudyFAB can be equated with a visit to the city centre. In addition, 33.3% of the users surveyed stated that they have used Schweinfurt city centre more frequently since StudyFAB opened. A total of 30.3% tend to agree with this statement. More than half of those surveyed use the city centre’s offerings, such as restaurants and retail outlets, more often than before StudyFAB opened. These findings suggest a positive descriptive link between StudyFAB utilization and local economic engagement, rather than a strictly causal economic effect.

Reaching level seven is linked to a change in the target group’s living situation. H2a states that the perceived quality of the Schweinfurt marketplace is higher for people who use a modern third space such as StudyFAB. H2b postulates that the perceived quality of stay of the Schweinfurt marketplace is higher for people who can use a modern third space such as StudyFAB.

However, the perceived quality of stay at the market square did not differ significantly (based on ANOVA) between users (M = 1.84), those classified as aware non-users (M = 1.85), and non-users (M = 1.87), F (2.90) = 0.20, p = 0.821. Descriptive data for the respective scales can be found in

Table 3. Comparison of non-users, aware non-users and users PSI scales; N = 93. Response scale from 0 to 3 (own illustration) [M = mean; SD = standard deviation].

Scales	Condition	M	SD	Item Count
Inclusiveness	Non-Users	1.92	0.72	2
	Aware Non-Users	2.00	0.63	2
	Users	2.05	0.69	2
Meaningful Activities	Non-Users	1.47	0.74	2
	Aware Non-Users	1.58	0.80	2
	Users	1.53	0.70	2
Comfort	Non-Users	2.05	0.59	2
	Aware Non-Users	1.83	0.61	2
	Users	1.82	0.54	2
Safety	Non-Users	2.37	0.60	2
	Aware Non-Users	2.37	0.56	2
	Users	2.02	0.61	2
Pleasurability	Non-Users	1.55	0.89	2
	Aware Non-Users	1.45	0.85	2
	Users	1.61	0.77	2

.

5. Impact Assessment

It is exceedingly difficult to evaluate this kind of project quantitatively. To solve this difficulty, we evaluated the project according to the principle of the impact staircase shown in Figure 1.

5.1. Input

The input for StudyFAB included modern interior, financial resources, staff time and volunteer efforts to establish and operate the facility and implement related programs and activities.

5.2. Output

The evaluation of StudyFAB’s outputs was conducted across the first three levels of the impact staircase from October 2023 to February 2024.

On Level 1, the key outputs included 94 operational days and three after-work events. Initially open four days per week in October, StudyFAB expanded to five days per week from November onwards.

On Level 2, the usage was tracked daily, revealing a total of 4372 visits (average: 45.51 visits per day). The number of visitors increased from 32/day in October to 55 per day in February, with a peak of 83 visitors on 31 January 2024. Visitors were 53.43% female (SD = 1.84%) and 46% male (SD = 1.89%). The largest age groups were 19–25 years (M = 35.56%. SD = 4.02%) and 26–65 years (M = 36.92%. SD = 7.54%), with younger visitors dominating in early 2024. Usage for work and study was the most common activity (M = 48.05%, SD = 3.31%), followed by reading/relaxing (M = 26.56%, SD = 3.15%).

Level 3 assessed user satisfaction through indicators like increasing visitor numbers and longer stays. StudyFAB achieved a Google rating of 5.0 (N = 60) and a Net Promoter Score (NPS) of 72.7 (Figure 2), indicating a high level of satisfaction and willingness to recommend the space to others. Survey respondents rated StudyFAB an average German school grade of 1.3 (SD = 0.47).

Figure 2. NPS of StudyFAB during usage 2023/2024 (own illustration).

Figure 2. NPS of StudyFAB during usage 2023/2024 (own illustration).

5.3. Outcome

On Level 4, the survey data showed that 78.8% of users perceived StudyFAB as enriching, with 36.4% reporting a positive shift in their perception of Schweinfurt’s city centre since using the facility.

On Level 5, StudyFAB’s central location has contributed to increased downtown visits. Notably, 39.4% of users visit multiple times per week and 33.3% report more frequent visits to Schweinfurt’s city centre since its opening. Over half of respondents also indicate increased use of downtown amenities, reflecting StudyFAB’s positive impact on local economic activity. Finally, on Level 7, the quality of stay in Schweinfurt’s market square should have improved.

This study examined the relationship between StudyFAB usage frequency and perceptions and utilization of Schweinfurt’s city centre. Two-sided Spearman’s rank correlations were calculated for ordinal data. Following Cohen’s (1988) guidelines [45], correlations were interpreted as small (|ρ| ≈ 0.10), medium (|ρ| ≈ 0.30), or large (|ρ| ≈ 0.50).

Statistical analysis indicated strong positive correlations between the frequency of StudyFAB usage and the overall rating of Schweinfurt (ρ = 0.68, p < 0.001), as well as positive perceptions of the city centre (ρ = 0.61, p < 0.001). Furthermore, moderate positive correlations were observed between StudyFAB utilization and the reported frequency of city visits (ρ = 0.41, p = 0.019), as well as the utilization of other downtown offerings (ρ = 0.43, p = 0.014). While these statistical links represent directional tendencies within the user group across the PHINEO impact framework levels, they indicate strong behavioural and evaluative associations rather than strictly isolated causal effects.

The positive feedback is often related to the ambience and modern design as well as the working and learning opportunities. The noise level and the small number of workstations were rated negatively. Nevertheless, it should be noted that around half of the participants did not mention any negative aspects. Participants expressed a desire for larger workstations with more seating options and individual workstations for meetings. A third of respondents were satisfied with the facilities and had no further requests. The presented empirical results demonstrate StudyFAB’s measurable effects within its target group across the PHINEO impact staircase levels. To contextualize these findings within the broader landscape of third space initiatives and assess StudyFAB’s relative positioning, the following section provides a comparative analysis with established projects, Utopiastadt Wuppertal and CityLAB Berlin (Section 6). This comparison highlights methodological strengths, scale differences, and complementary impact logic among urban social innovation hubs.

6. Comparative Analysis

6.1. Description

The following comparison situates StudyFAB Schweinfurt within the context of two other third space initiatives, Utopiastadt in Wuppertal and CityLAB Berlin, to identify similarities and differences in their mission, objectives, governance structures, service profiles and impact mechanisms, and to derive transferable strategies for the further development of StudyFAB. The focus is on third spaces that function as hybrid meeting and learning spaces at various urban scales, repurpose vacant properties or existing buildings, and involve civil society and institutional actors in co-productive formats. The section first presents the selected projects within their urban context (objectives, methods, target groups, offerings, initial results), then carries out a systematic comparison based on defined criteria, and, building on this, discusses the transferability of key elements to StudyFAB.

6.2. Selection of Comparison Projects

Three key categories of comparability are used to select the comparative projects: firstly, the functional role of the projects as third spaces in the context of structural change and pressure for transformation (e.g., dealing with vacant premises in city centres, repurposing existing buildings); secondly, the nature of the initiative as a hybrid space for encounter and experimentation, bringing together creativity, education, digitalisation and social innovation; thirdly, the target groups, each comprising a mix of students or young urban makers, the local business community, civil society actors and the interested urban public. Finally, the three cases cover different urban scales (medium-sized town centre, neighbourhood, metropolis), which allows conclusions to be drawn about scalable elements of third spaces.

6.3. The Projects

This section provides a brief overview of each of the selected third space initiatives. For each project, it describes the objectives, key methods and formats, the target groups addressed, and the results and impacts observed to date. It then outlines the urban context and relevant background conditions of the respective city or region to situate the projects within their socio-spatial context and lay the groundwork for the subsequent analytical comparison.

6.3.1. Utopiastadt, Wuppertal

Utopiastadt in Wuppertal, Germany (ca. 350,000 inhabitants) serves as an apt first comparative case to StudyFAB: Despite the larger city size, Wuppertal shares Schweinfurt’s (ca. 54,000 inhabitants) challenges of economic structural change and image problems, with both projects transforming vacant spaces into creative, community-oriented hubs [46,47]. Emerging from the interim use of the disused Mirker Bahnhof, Utopiastadt mirrors StudyFAB as a multifaceted third space offering open social exchange, co-working, workshops, urban gardening, and events that actively contribute to urban development [48,49]. Target groups overlap in addressing students, founders, local initiatives, and the interested public, though Utopiastadt’s civil society focus contrasts with StudyFAB’s university affiliation [46].

Context and Origins

Utopiastadt originated in 2014 from the temporary use of Wuppertal-Mirke’s abandoned railway station (built 1882, disused 1991) in the structurally weak Mirke neighborhood [46,49]. It positions itself as a permanent “idea space and laboratory for the city of tomorrow” [48].

Objectives and Methods

The goal is an open, public-benefit third space combining urban development, neighborhood work, and socially engaged art across ~3000 m² [47,48]. Spaces remain deliberately “unfinished” to foster user appropriation and co-design [46].

Offers and Formats

Features include the “Hutmacher” café, concerts, readings, open workshops, participatory formats, neighborhood festivals, and guided tours on history and regeneration [48,50]. The site functions as a real lab for work, culture, education, mutual aid, and experimental urbanism [47].

Organizational Structure and Target Groups

Operated by Utopiastadt gGmbH (founded 2015, civil society-led), funding comes from café revenues, grants, events, and land acquisition (Mirker Bahnhof donated 2016; 11,100 m² purchased 2018) [46,50]. It targets creatives, residents, initiatives, students, and founders; it has improved neighborhood image but faces volunteer burnout and funding challenges [46].

Conclusion

Utopiastadt and StudyFAB are comparable as both repurposed vacant sites (Mirker station vs. Schweinfurt factory) into participatory third spaces addressing structural change through co-working, workshops, gardening, and events—differing in governance (civil society vs. university) and scale [46].

6.3.2. CityLAB, Berlin

CityLAB, Berlin, Germany serves as a second comparative case to StudyFAB, creating a hybrid third space between public administration, urban society, and knowledge institutions in Berlin’s former Tempelhof Airport [51,52]. Both projects address digital and social transformation through open learning spaces and position themselves as experimental sites for “the city of tomorrow”, differing primarily in scale and institutional embedding [51].

Context and Origins

CityLAB Berlin opened in 2019 within the iconic former Tempelhof Airport building—a symbol of Berlin’s urban history now serving as a smart city hub—situated in a metropolis of over 3.5 million inhabitants marked by digitalization, social diversity, and complex administrative structures [51,53].

Objectives and Methods

CityLAB aims to function as a public innovation lab for the digital city, uniting administration, citizens, academia, and startups in public-benefit solutions. Methodologically, it employs user-centred development (service design, co-design), rapid prototyping, open data, and agile software development to transform ideas into testable prototypes, viewing digitalization as a tool for improving governance, participation, and urban quality of life [51].

Offers and Formats

CityLAB integrates co-working spaces, digital workshops, exhibition and event areas into an open experimental lab, offering workshops, hackathons, project studios, smart city exhibitions, and regular community formats where citizens and administrators co-create solutions. Mobile formats like the “Kiezlabor” bring participation and prototyping directly into Berlin’s neighborhoods [51,54].

Organizational Structure and Target Groups

Operated by the Technologiestiftung Berlin in close cooperation with the State of Berlin, CityLAB functions at the intersection of urban society, administration, and academia. Target groups include public servants, civil society initiatives, research institutions, startups, and engaged citizens shaping Berlin’s digital future. Recognized as a smart city development benchmark, it faces challenges integrating experimental approaches into administrative routines and securing long-term funding [51].

Conclusion

CityLAB Berlin and StudyFAB are comparable as both repurposed unused spaces (Tempelhof vs. Schweinfurt factory) into hybrid third spaces with co-working, workshops, events, and prototyping to advance digital/public-benefit urban development—differing in institutional embedding (administration/science vs. university) and urban scale [51].

6.4. Comparison of Projects

6.4.1. Context and Origins

StudyFAB was launched in 2023 as a pilot project of the “SchweinfurtFABulous” initiative in vacant shop premises (150 m²) on Schweinfurt’s market square. It responds to inner-city vacancy rates, declining footfall and a ‘downward curve’ effect (ageing population, online retail) in this medium-sized town (approx. 54,000 inhabitants).

Utopiastadt emerged from 2014 onwards in the significantly larger city of Wuppertal (approx. 350,000 inhabitants) in the structurally weak district of Mirke, arising from the temporary use of the disused Mirke railway station, with the aim of re-programming a neglected area along the Nordbahntrasse and establishing it as a neighbourhood anchor. Here, a formerly neglected piece of infrastructure along the Nordbahntrasse is gradually being transformed into a public-benefit-oriented cultural and urban development hub [46].

CityLAB Berlin opened in 2019 in a section of the former Tempelhof Airport and, against the backdrop of Berlin’s Smart City Strategy, addresses the digital transformation of public administration and urban society [51,53]. It is situated in a metropolis with complex administrative structures and a highly developed innovation landscape.

What the three projects have in common is that they repurpose existing buildings in situations of change as innovative testing grounds and utilize them as third spaces; they differ primarily in terms of scale (small-to-medium-sized town centre, neighbourhood, metropolis) and initial focus (city centre regeneration, neighbourhood development, smart city). StudyFAB is distinguished by its university-based, research-driven focus (see PHINEO evaluation in the paper).

6.4.2. Objectives and Methods

StudyFAB pursues two closely linked objectives: as the THWS’s inner-city presence, it aims to highlight student life, startup culture and cooperation with the local economy, whilst simultaneously contributing to the revitalisation of the city centre as a social innovation hub. The focus is less on a massive increase in footfall and more on the question of whether a social innovation hub can change the perception, quality of stay and usage behaviour of a clearly defined target group; methodologically, the project works with a mix of open work and learning zones, curated events and accompanying mixed-methods impact monitoring (counts, usage data, surveys, impact indicators).

Utopiastadt focuses more strongly on urban development for the common good, cultural revitalisation and the empowerment of civil society [46]. The guiding principle is the idea of an ‘unfinished’ place that allows for appropriation: temporary use, long-term self-organization, artistic and social projects, and ongoing architectural transformation serve as key methods for revitalising the neighbourhood and testing new urban practices [47,48].

CityLAB Berlin sees itself as a public innovation laboratory for the ‘digital city for all’ [53]. At its heart lies the co-productive development of public-good-oriented digital solutions by public administration, civil society, academia and startups. Methodologically, the approach is dominated by design thinking, service design, open data, agile development and experimental pilot projects with Berlin’s public authorities [51].

By comparison, StudyFAB sits between the two: socially, spatially and community-oriented like Utopiastadt, but with a more programmatically defined, research-based and experimental logic that brings it closer to CityLAB.

6.4.3. Facilities and Formats

Spanning around 150 m², StudyFAB offers a hybrid space comprising co-working stations, study and project zones, small meeting areas and communal spaces. This is complemented by workshops, information and networking events, startup initiatives, hands-on activities with regional businesses, and experimental events (e.g., ‘Experience Days’ featuring technology demonstrations). Use is primarily work- and study-oriented; empirically, working/studying dominates, followed by reading/relaxing, with rising visitor numbers, very high satisfaction and an NPS of over 70.

Utopiastadt combines co-working, workshops, urban gardening, repair cafés, studios, the ‘Hutmacher’ café as a meeting place, and a wide range of cultural and participatory formats—from concerts and readings to festivals and neighbourhood celebrations, as well as workshops, participatory formats and guided tours [46,47]. The venue is thus equally a cultural centre, a neighbourhood space, a workshop and an urban laboratory, covering a significantly broader spectrum of everyday life and leisure activities [48].

CityLAB Berlin combines co-working spaces, a digital workshop, exhibitions, and event areas, and uses them for hackathons, innovation workshops, project labs, smart city exhibitions, community meetups and co-design processes involving local government [52]. In addition, there are mobile formats that go out into the boroughs to involve citizens and local government in innovation processes, such as the Kiezlabor [54].

In summary, StudyFAB lies between the two comparison cases in terms of the breadth of its offering: more focused and work-related than Utopiastadt, and more socially spatial and community-oriented than CityLAB; this profile can be specifically refined in future development (e.g., more cultural formats modelled on Utopiastadt or more structured innovation labs based on the CityLAB approach).

6.4.4. Funding and Target Groups

StudyFAB was initially funded by the City of Schweinfurt and THWS as part of a federal programme; currently, the City covers the rent and THWS covers the staff costs. The space is managed by a full-time project coordinator employed by THWS, who is also the managing director of the non-profit sponsoring association netSWerk e.V., supported by several student assistants and a voluntary board. In the future, the association is expected to take on an increasing share of the financing and coordination through donations, sponsorship and rentals. The target groups are students, school pupils, those interested in starting a business, local businesses, freelancers and interested members of the public; the study shows that younger users and working professionals make intensive use of the space, thereby changing their city usage patterns.

Utopiastadt is run by a civil society-oriented gGmbH, whose funding is derived from catering revenue, project and grant funding, events and the gradual purchase of land; the City of Wuppertal is a strategic partner, without directly managing the site [46,55]. The target groups are creative professionals, residents, initiatives, students, startup founders and the wider public, with a strong focus on residents and the cultural scene [46,47].

CityLAB Berlin is a project run by Technologiestiftung Berlin in close cooperation with the State of Berlin and is thus firmly embedded in the city’s smart city governance framework [51,56]. Its target groups include public sector employees, civil society organizations, research institutions, tech companies and interested citizens who are contributing to Berlin’s digital transformation [51].

In terms of governance, StudyFAB represents a university-affiliated, locally rooted ‘third space’ with a hybrid funding structure (university + city + association); Utopiastadt is a civil society-led urban laboratory with a strong focus on the public good [46,48]; and CityLAB is an institutionally mandated innovation laboratory commissioned by the city [51]. For the further development of StudyFAB, different role models can be derived from this: as the university’s ‘Third Mission Hub’ (like CityLAB), as a more self-organised, public-good-oriented urban-making space (like Utopiastadt), or deliberately as a hybrid form that combines elements of both models.

The systematic comparison (

Table 4. Systematic criteria-based comparison of third space initiatives: StudyFAB, Utopiastadt, and CityLAB (own illustration).

Criterion	StudyFAB (Schweinfurt)	Utopiastadt (Wuppertal)	CityLAB (Berlin)
Governance	University-affiliated, locally rooted structure; cooperation between the university (THWS), the city, and a non-profit association (netSWerk e.V.).	Civil society-led structure (Utopiastadt gGmbH); the city acts as a strategic partner without a direct management role.	Institutionally mandated structure; operated by Technologiestiftung Berlin with close, direct coupling to the state administration.
Funding	Hybrid (initial federal grant); currently, city covers rent and THWS covers staff costs; future aims target higher self-sustainability via the association.	Diversified self-sustainability; funded through café revenues (“Hutmacher”), events, project grants, and own land ownership.	Institutionally secured; regular funding within the framework of the State of Berlin’s Smart City Governance via Technologiestiftung.
Target Groups	Focused on university and school students, founders, local businesses/SMEs, and the academically interested public.	Broadly diversified; local neighbourhood (Mirke district), creative scene, local initiatives, activists, and the general urban public.	Intersection of public administration (civil servants), tech startups, academia, civil society, and politically engaged citizens.
Spatial Size	Approx. 150 m2 in a central, formerly vacant retail space directly located on the market square.	Campus scale; approx. 3000 m2 of usable space in a former railway station and approx. 11,100 m2 of surrounding open grounds.	Large-scale innovation hub located in a section of the former Tempelhof Airport building (metropolitan hub).
Offers & Formats	Integrated co-working and study zones, startup consulting, after-work networking events, and technology demos (“Experience Days”).	Cultural centre and neighbourhood café; open workshops, urban gardening, repair cafés, concerts, readings, and participatory urban research.	Digital real-world lab; hackathons, co-design workshops with authorities, agile prototype development, smart city exhibitions, and mobile labs (“Kiezlabor”).
Measurable Impacts	Standardized PHINEO metrics: High target group acceptance (Ø 45.5 visits/day), excellent NPS of 72.7; verifiable behaviour changes (33.3% visit downtown more frequently). No macroscopic footfall changes on the square.	Qualitative-structural: Sustainable revitalization and image improvement of an entire neighbourhood; established as a central civil society actor in Wuppertal.	Administrative scaling: Successful integration of digital prototypes (e.g., AI assistants) into administrative routines; broad public participation via mobile formats.

) across the defined criteria illustrates that while the three initiatives operate on fundamentally different urban scales, they share a complementary logic of urban transformation. While Utopiastadt Wuppertal functions as a large-scale neighbourhood hub driven primarily by social self-organization and community integration, and CityLAB Berlin acts as a metropolitan catalyst for administrative and digital modernization, StudyFAB Schweinfurt positions itself precisely as a focused “Third Mission Hub” within the socio-spatial context of a medium-sized town. From a methodological standpoint, StudyFAB addresses a critical gap in the contemporary third space literature. While the impacts of the benchmarks in Wuppertal and Berlin are predominantly argued through qualitative case studies, project volume, or macroscopic ecosystem growth, StudyFAB provides a granular, quantitatively validated evidence base at the micro-level of individual users by applying the PHINEO impact framework. The statistically significant, strong positive correlation (ρ = 0.68, p < 0.001) between StudyFAB usage frequency and an improved perception of Schweinfurt’s downtown core demonstrates that even small-scale physical interventions (150 m²) can prompt substantial behavioural and attitudinal shifts within targeted user groups. The fact that macroscopic indicators—such as the overall city-wide pedestrian counts on the market square—remained largely unaffected is a direct consequence of spatial capacity constraints rather than a reflection of conceptual underperformance. For the strategic evolution of the project, this comparative matrix highlights clear transferable strategies. StudyFAB can scale both qualitatively and quantitatively by either adopting civil society formats from Wuppertal (e.g., hosting “FabLab workshop evenings” or repair events to extend operational vitality) or deploying modular, mobile approaches inspired by Berlin (e.g., establishing temporary ‘StudyFAB pop-ups’ in scattered inner-city vacancies).

6.5. Shared Logic of Impact

All three locations generate impacts with different focal points. A direct comparison shows that, unlike many established urban laboratories such as Utopiastadt Wuppertal [46] and CityLAB Berlin [51], StudyFAB has a particularly extensive empirical database for describing social acceptance, usage, participation and inclusion (e.g., 45.5 visits/day, NPS 72.7, ρ ≈ 0.68 between usage and city centre evaluation; see Section 5).

Whilst Utopiastadt and CityLAB demonstrate their impact primarily through qualitative case studies, high visitor numbers, their role as central locations within the neighbourhood or in smart city governance, and ongoing projects and new forms of cooperation [49,51], StudyFAB has standardised metrics based on the PHINEO impact framework. These include high usage intensities, very positive satisfaction ratings (including the Net Promoter Score), demonstrable participatory co-creation of the space and programme, behavioural changes in favour of the city centre, and significant correlations between usage frequency, perception of the city centre and behaviour whilst in the area.

At the same time, it becomes clear that a single, physically small third space such as StudyFAB, despite these clearly measurable effects at the level of the target group, cannot yet exert a significant influence on macroscopic indicators such as the overall footfall in the city centre. Taken together, the three examples suggest that third spaces should be understood as effective but complementary building blocks of urban transformation: Utopiastadt and CityLAB primarily with regard to structural and governance-related changes [46,51], and StudyFAB with regard to finely detailed, quantitatively documented effects on the perception, behaviour and inclusive participation of the users directly reached.

6.6. Transferable Strategies from the Benchmark Projects

The empirical findings from StudyFAB align well with the impact frameworks of established urban laboratories such as Utopiastadt [46] and CityLAB Berlin [51] and offer concrete approaches for scaling up the initiative in Schweinfurt. Whilst StudyFAB has already achieved high levels of acceptance (NPS 72.7, rating 1.3) and target group-specific behavioural changes (more frequent visits to the city centre), Utopiastadt and CityLAB demonstrate strategies for long-term impact at the neighbourhood and governance levels [49,51].

6.6.1. From Utopiastadt (Community Integration and Self-Organization)

Hybrid financing and self-sustainability: Utopiastadt secures long-term independence from funding through catering (the ‘Hutmacher’ café), events and the gradual purchase of land—a model that StudyFAB could adopt by opening its own café or increasing event bookings to boost self-sustainability [46,55].

Wide range of everyday activities: Repair cafés, urban gardening and cultural events make Utopiastadt a neighbourhood hub; StudyFAB could complement this with ‘FabLab workshop evenings’ or ‘city centre repair events’ to extend opening hours and attract passers-by [47].

6.6.2. From CityLAB Berlin (Innovation Governance and Scaling)

Implementation of prototypes: CityLAB brings digital applications (e.g., ‘Fairgnügen’ for 700,000 users, an AI assistant for all employees) into administrative practice; StudyFAB could implement this with ‘city centre apps’ (e.g., shared pedestrian navigation or event finder) through collaborations with city administration [51].

Mobile formats: “Kiezlabor” and “Stadtlabor2Go” are rolled out to Berlin’s districts; StudyFAB could test ‘StudyFAB pop-ups’ across Schweinfurt’s city centre based on positive target group outcomes [54].

6.7. Adaptations to Schweinfurt’s Local Conditions

Schweinfurt’s context as a medium-sized town (54,000 inhabitants, strong university presence, vacant premises) requires specific adaptations:

Scaling rather than 1:1 copy: Unlike Utopiastadt’s single-location transformation (several thousand m², 2500 peak visitors), Schweinfurt’s scattered small vacancies (50–300 m²) favour modular scaling through ‘StudyFAB 2.0’ locations and pop-ups, creating synergy across multiple hubs [47].

University focus: StudyFAB should build its unique “Third Mission Hub” position, leveraging THWS, MINT population and schools for Open Social Innovation—startup accelerators with regional automotive cluster, innovation workshops, dual projects connecting students with SMEs.

Continuing impact measurement: StudyFAB’s PHINEO-based metrics (45.5 visits/day, NPS 72.7, ρ ≈ 0.68) set it apart from qualitative benchmarks. Scaling requires a ‘Local Social Index’ (LoSI) tracking usage, satisfaction and city centre effects across locations for evidence-based optimisation.

In summary, StudyFAB should scale through modular consolidation, university profiling and refined impact monitoring. Whilst Utopiastadt and CityLAB show long-term embedding strategies, StudyFAB combines these with evidence-based management for medium-sized towns [46,51].

7. Discussion

The results suggest that StudyFAB has not led to a measurable increase in overall pedestrian frequency in downtown Schweinfurt, but it coincides with positive perceptions and altered visit patterns within its target user group, consistent with the targeted dynamics observed in Utopiastadt (targeted neighbourhood activation) and CityLAB Berlin (specific governance improvements) [46,51]. The data indicate that StudyFAB is linked to an enhanced downtown experience for its active users, potentially contributing as a supportive element to long-term urban revitalization efforts.

The lack of significant change in pedestrian numbers overall may be attributed to multiple factors. On average, StudyFAB attracted 46 daily visitors accounting for only 0.15% of the market square’s daily pedestrian frequency of 30,724 in 2023/24. The limited size of StudyFAB appr. 150 m² restricts its capacity to significantly influence the vibrancy of the market square vs. Utopiastadt’s campus-scale with 11,100 m² [47]. Revitalization efforts would require either an expansion of StudyFAB or additional projects of similar nature. Moreover, pedestrian frequency in urban areas is influenced by multiple factors, making causal relationships difficult to establish [29]. However, the positive user feedback and increased downtown visits among StudyFAB users indicate potential for long-term impact.

While StudyFAB did not improve the overall perceived quality of stay significantly, it did reach Stage 5 of the impact staircase. At this stage, changes in awareness and perceptions within the target group are evident. Survey results show that 75% of StudyFAB users reported visiting the city centre more frequently due to StudyFAB and 66% perceived the city centre more positively. Reaching Stage 5 demonstrates that StudyFAB has successfully influenced its target group, contributing to urban revitalization efforts through increased engagement and improved perceptions of Schweinfurt’s downtown area.

7.1. Methodological Discussion

This study’s methodology presents certain limitations regarding sample size and statistical power that warrant careful consideration. A primary concern is the psychometric reliability of the measurement instruments. The shortened version of the Public Space Index (PSI), adapted from Mehta (2014) [42], demonstrated poor internal consistency across the sampled dataset, yielding an overall Cronbach’s alpha of α = 0.52. Certain subscales fell significantly below acceptable psychometric thresholds. This severe reduction in items—from the comprehensive original framework to merely two items per dimension—compromised the instrument’s capacity to reliably capture the multidimensional constructs defining the quality of stay [43]. Consequently, minor variations in participant perceptions may have disproportionately skewed the scale scores, muddying the statistical boundaries between the three experimental groups.

Furthermore, the small sample size of approximately n = 30 participants per group (N = 93 in total) severely restricts the statistical power (1 − β) of the quantitative analyses. In a one-way analysis of variance (ANOVA), a sample size of this magnitude is mathematically underpowered to detect small-to-medium localized effects with sufficient confidence. Under standard statistical assumptions (α = 0.05), detecting a medium effect size (f = 0.25) with a power of 80% would typically require a significantly larger sample. Because the statistical power is limited, the probability of committing a Type II error—failing to reject a false null hypothesis and mistakenly concluding that StudyFAB had no impact on the broader market square’s quality of stay—remains high. This limitation narrows the representativeness of the findings and dictates that the non-significant ANOVA result (p = 0.821) regarding the market square’s quality of stay must be interpreted as a reflection of restricted statistical sensitivity rather than a definitive absence of an effect.

A further significant methodological limitation arises from the temporal asymmetry between the collection of automated pedestrian frequency data and the administration of the participant survey. While the automated foot traffic counts primarily captured urban dynamics during the winter period, the survey was conducted during the subsequent spring months. This seasonal discrepancy introduces a confounding factor regarding the perceived quality of stay and urban behaviour. Urban space utilization is highly subject to seasonal fluctuations; winter months typically induce utility-driven, time-sensitive visits characterized by low stationary dwell times due to adverse weather. Conversely, spring conditions inherently elevate the general baseline for the perceived quality of stay, encouraging leisurely lingering and open-air activities regardless of specific local interventions. Consequently, comparing the objective, winter-bound macro-level pedestrian frequencies with the subjective, spring-bound micro-level perceptions limits the structural alignment of the datasets and requires that the cross-sectional correlations be interpreted with appropriate caution regarding seasonal variance [57,58].

The ex post facto field design further compounds these limitations by introducing self-selection biases, as participants were grouped based on their natural usage habits rather than through random assignment [59]. Uncontrolled environmental externalities during the 14-day data collection period—such as sudden weather shifts or variations in daytime foot traffic—may have systematically introduced variance into the respondents’ evaluative states. Similarly, while the automated pedestrian counting device provided longitudinal trends, its reliance on tracking active mobile network connections introduces hardware-related inaccuracies. It fails to record individuals without devices and potentially overcounts those carrying multiple devices. Future research aimed at scaling this intervention should deploy larger, randomly sampled cohorts to elevate statistical power and replace network-based tracking with high-precision optical laser systems or automated long-range wide-area network (LoRaWAN) multi-sensors to isolate external noise.

7.2. Limitations and Research Outlook

StudyFAB itself reduces the vacancy rate by utilizing vacant properties. It would therefore be interesting to know whether the project influences the attractiveness of the city in such a way that the vacancy rate in the surrounding neighbourhood is reduced. To check this, however, the existing vacancies would have to be compared over years before, during and after the project period.

Furthermore, the comparative benchmarking against highly institutionalized initiatives, such as CityLAB Berlin and Utopiastadt Wuppertal, necessitates a rigorous discussion of urban scaling and spatial transferability constraints [60]. CityLAB Berlin benefits from an embedded governance model within a major metropolis, operating with extensive municipal backing and a vast ecosystem of tech-driven stakeholders. Similarly, Utopiastadt Wuppertal functions as an organic, citizen-led ‘co-design campus’ that leverages a massive physical brownfield infrastructure and a dense socio-cultural catchment area to foster long-term community activation. Transferring these frameworks to a medium-sized, industrialized city like Schweinfurt reveals significant scale-dependent limitations. According to urban scaling theory, metropolitan areas possess distinct socioeconomic dynamics, higher internal network density, and a critical mass of creative capital that smaller urban centres inherently lack [61]. Consequently, while the qualitative impact logics—such as civic participation, cross-sectoral networking, and the reclamation of vacant spaces—are structurally transferable to Schweinfurt, the quantitative scale of impact remains constrained. StudyFAB cannot mirror the self-sustaining, macroscopic urban transformation observed in Wuppertal or Berlin due to its limited spatial footprint (150 m²) and smaller target demographic. Future benchmarking matrices must therefore introduce calibrated indicators that normalize impact metrics relative to municipal population, available funding volumes, and spatial dimensions to avoid structural asymmetries in comparative urban research.

A notable limitation of this study concerns the potential influence of uncontrolled external confounding variables on city centre utilization and visitor perceptions. Methodologically, urban foot traffic and evaluative measures of city centres are highly susceptible to temporal, seasonal, and situational dynamics, such as seasonal variations, weather conditions, socio-cultural events, or general macroeconomic frameworks. Because data collection represents a specific temporal snapshot, it is mathematically challenging to completely isolate the variance explained by StudyFAB from these overarching environmental factors. For instance, favourable weather or concurrent local events may independently increase both the frequency of city visits and general positive sentiment toward the downtown area. To mitigate these limitations and track long-term dynamics, future research should explore the long-term impact of StudyFAB. Qualitative studies incorporating in-depth interviews with StudyFAB users and local business owners could provide richer insights into the perceived benefits and challenges of the project. Furthermore, incorporating longitudinal data designs or cross-environmental control variables in upcoming studies will help to statistically control for atmospheric, seasonal, and event-driven externalities, thereby more robustly isolating the intervention’s direct impact [62].

The benchmark analysis (Ch. 6) suggests scaling StudyFAB modularly (like CityLAB’s Kiezlabor) rather than single-location expansion (Utopiastadt model), leveraging Schweinfurt’s scattered vacancies for networked impact [54]. Comparative studies of similar third space initiatives in other German cities would help to identify best practices and contextual factors that influence success. Investigating the potential for StudyFAB to evolve into a more self-sustaining model reducing reliance on governmental funding would also be beneficial. Based on this study’s findings, several recommendations can be made for improving the effectiveness of StudyFAB and similar urban revitalization initiatives. These include increasing visibility and awareness, expanding services to attract a wider range of users, and collaborating with other organizations to create a more comprehensive downtown experience.

8. Conclusions

This study provides valuable insights into the potential of third spaces as a tool for urban revitalization, complementing the benchmark analyses of Utopiastadt and CityLAB Berlin from Section 6 [46,51].

While StudyFAB has not had an impact on overall pedestrian frequency in Schweinfurt, it has demonstrated the potential to engage a specific user group and improve their perception of the inner city. By creating a welcoming and engaging space that meets the needs of students, entrepreneurs, and residents, StudyFAB has contributed to the social and economic vitality of Schweinfurt’s city centre significantly.

The assessment of the city centre by users and non-users was the same. However, it was shown that StudyFAB has a positive effect on its target group. The centre’s operations and events are very well received by the target group. In addition, a positive change in the target group’s perception of the city centre and an increase in the use of the city centre were observed. To increase the informative value, it is recommended that a further survey and analysis of the tracking data be conducted after the end of the funding period to re-evaluate the overall project and its impact. A legal form such as a limited liability company with a self-sustaining business model should be developed to ensure the continuation and independence of StudyFAB. In addition, further funding as one of the financing columns should be acquired to transform interim use into permanent use. In addition, the project’s name should be rebranded to make the concept easier to understand.

Beyond its immediate relevance for Schweinfurt, this study contributes to the broader sustainability discourse by showing that a small-scale, resource-efficient social innovation can generate measurable social value: improved perceptions of the city centre, increased engagement, and sustained user satisfaction, without requiring large-scale physical or financial investment. In this sense, StudyFAB illustrates a socially and economically sustainable pathway for revitalizing shrinking city centres, in line with this journal’s aim of advancing the environmental, cultural, economic, and social sustainability of human settlements, and with SDG 11 (Sustainable Cities and Communities). Future research should also examine whether such low-footprint interventions yield environmental co-benefits (e.g., reduced vacancy-related resource waste) to capture their sustainability contribution more comprehensively.

Key recommendations from Section 6 include modular scaling through ‘StudyFAB 2.0’ pop-ups across city centre vacancies like CityLAB’s Kiezlabor [54], hybrid financing via café/events modelled on Utopiastadt’s Hutmacher concept [55], and strengthening the university Third Mission through THWS integration with lectures and startup accelerators. These approaches complement cooperation with other initiatives, e.g., modern Café concepts or open art labs.

The findings suggest that while StudyFAB has been successful in engaging a specific user group, its impact on overall pedestrian frequency and perceived quality of stay in the Schweinfurt marketplace has been limited. This study contributes to closing the research gap on social innovation and shows the positive effects of this type of intermediate use. Nevertheless, more funding should be invested in measuring social innovation to make the data more reliable and comparable. As Section 6 demonstrates, StudyFAB combines Utopiastadt’s community strategies and CityLAB’s governance innovations with evidence-based PHINEO metrics, positioning Schweinfurt as a medium-sized town model for scalable third spaces [46,51]. The concept itself counteracts the desolation of city centres using vacant property.

It remains to be seen whether such a project can prevent or further reduce further vacancies by increasing the attractiveness of the city centre. The project therefore has enormous potential to make sensible and efficient use of vacancies and to enhance the city centre. The StudyFAB approach has potential over time to develop into a highly frequented social public innovation space.

However, this study also highlights the challenges associated with implementing such initiatives including the need for sustainable funding, strong partnerships and ongoing adaptation. Future research should focus on addressing these challenges and exploring the potential for third spaces to play a broader role in shaping the future of urban life.