Salaborsa Library: reading a public space as an interface
A semiotic study of how architecture, sound and everyday behavior help people understand where to talk, study, pass through or stop inside a public library.
- Role
- UX Researcher & Spatial Systems Analyst
- Team
- Duration
- 6 months (Research & Ex-Post Analysis)
- Client
- Salaborsa Library, Bologna, Italy
The project in one minute
The Challenge
A public space has to allow activities that don't fit together, like conversation, passing through and silent study, without turning into a sequence of prohibitions and instructions.
My contribution
- Conducted spatial mapping and architectural analysis across three floors
- Developed threshold taxonomy using semiotic frameworks
- Performed acoustic ethnography with sound recordings and spectrograms
Results and scope
14,000m² public space analyzed across three floors and multiple functional zones
Published in E|C
This research was published as a scientific article in E|C, the journal of AISS, the Italian Association for Semiotic Studies.
The Challenge
What I was responsible for
- Conducted spatial mapping and architectural analysis across three floors
- Developed threshold taxonomy using semiotic frameworks
- Performed acoustic ethnography with sound recordings and spectrograms
- Documented user journeys and behavioral transitions
- Applied semiotic analysis using Greimas, Lotman, and de Certeau frameworks
- Created visualizations of acoustic 'fingerprints' for each space
- Analyzed emergent patterns versus intended design strategies
A public space has to allow activities that don't fit together, like conversation, passing through and silent study, without turning into a sequence of prohibitions and instructions.
Salaborsa is a public library of about 14,000m² in the center of Bologna. I studied it as a system of signals: signs and paths, but also materials, thresholds, sound levels and practices that change from one zone to the next.
The study was an ex-post analysis with no redesign intent: I wanted to understand how a place already in use manages to communicate different rules without constantly spelling them out, and which parts of that communication could be observed.
"People who walk in need to understand quickly what they can do in each zone, often without stopping to read a sign or already knowing the building."
The study made it possible to describe these passages as a coherent system of signals, without attributing to the space design intentions the research couldn't verify.
Changes in material, transparency, openness and noise often coincided with changes in how people behaved. Transitions were perceptible even where no sharp threshold marked them.
Research
Spatial analysis
Threshold taxonomy
Catalogued different boundary types using Zilberberg's distinction between 'limits' (rigid barriers) and 'thresholds' (gradual transitions). Study hall doors create acoustic impermeability while balcony edges allow acoustic permeability.
The Piazza Coperta as a reference point
The Piazza Coperta (central atrium) works as what Kevin Lynch would call an 'imageability node': it's visible from every floor, offers a point of orientation and lets people 'reset' their behavior between one zone and the next.
Isotopic analysis
Identified recurring semiotic categories: /Centrality/ (physical center → social hub → acoustic beacon), /Transparency/ (visual glass → archaeological visibility → institutional openness), /Gradient/ (acoustic levels → behavioral freedom → spatial progression).
Acoustic ethnography
Acoustic syntagms
Each space had a distinct acoustic signature, stable across different times and days. Visualized as spectrograms, these signatures ('acoustic syntagms') work as an orientation system that doesn't rely on signage.
Sound level gradient
45-50 dB range between the loudest (café) and quietest (study hall) zones. Progressive acoustic zoning guides behavior without the need for signage.
"Culture is fundamentally polyglot, and its texts are always realized in at least two semiotic systems."
— Jurij Lotman (1985) - theoretical framework
Path documentation
Behavior changes across thresholds
Observed behavior shifted across acoustic and spatial thresholds without requiring explicit instructions, suggesting that sound and permeability were functioning as part of the wayfinding system.
Strategies and tactics
The institutional design (strategies) left room for users to appropriate the space (tactics). Students using the transitional balconies for phone calls, parents creating informal play areas: tactical uses the space absorbed without problems.
Transition zones
3-5 meters of gradual acoustic change between the main spaces. In these buffer zones people adjust their behavior gradually, without abrupt shifts.
Key Insights
Wayfinding is behavioral as well as spatial
People moving through the library need to understand where they are and also what behavior the zone allows. Sound contributes to that reading alongside sightlines, barriers and furniture.
Gradients can communicate transitions without instructions
From the café and central atrium toward reading and study areas, acoustic and architectural cues become progressively more constrained rather than switching abruptly at a single boundary.
Use reveals what the plan alone cannot
Phone calls on balconies, informal pauses and family activity show how people appropriate transitional zones. The relevant question is whether the architecture can absorb those tactics without collapsing the distinctions between spaces.
Research questions
How does the space communicate behavior without explicit instruction?
Map the interaction between visual, acoustic and spatial cues across different zones.
Which patterns are planned, and which emerge through use?
Compare institutional spatial strategies with the everyday tactics through which people appropriate them.
What can transfer to interface design?
Extract principles about thresholds, redundancy and progressive disclosure, without claiming that a physical environment translates literally into a digital product.
Guiding Principles
Observe before prescribing
The study describes how an existing system communicates; those mechanisms are not design interventions of mine.
Reading the space
Interactive diagram
An acoustic gradient of behaviour
Select a node to highlight its connections and read the design decision behind it.
Café
The analysis describes the café as the area of greatest behavioural freedom: conversation and social activity are expected.
Connected to: Covered square
Interpretive sequence from the spatial analysis, not a floor plan or an accessible route guide.
Pattern 1: acoustic gradient
How can people recognize a shift from social to study-oriented space before reaching an explicit rule or sign?
Alternatives considered
- Extensive signage explaining behavioral expectations (visual clutter, often ignored)
- Staff intervention to guide behavior (not scalable, interrupts user autonomy)
- Environmental design that communicates through sensory cues (invisible, intuitive)
I interpreted the progressive change in sound level between social and study areas as part of the space's behavioral wayfinding.
The acoustic change coincided with shifts in permeability and observed behavior, suggesting a gradient rather than a single binary boundary.
Trade-off: This is an interpretive relationship: the study can't isolate sound from the other spatial cues that change with it, so it doesn't test it causally.
Pattern 2: transparent threshold
How can adjacent activities remain perceptually connected while still supporting different behavioral expectations?
Alternatives considered
- Solid walls for complete separation (destroys visual unity, creates isolated zones)
- No barriers (allows acoustic and behavioral bleeding between incompatible uses)
- Glass barriers for acoustic control with visual connection (maintains unity while enabling separation)
Glass thresholds were analyzed as hybrid boundaries: visually permeable but acoustically more restrictive.
That mismatch lets people maintain orientation to the larger library while receiving a different cue about acceptable behavior inside the enclosed zone.
Trade-off: The analysis describes how the boundary functions in use; it does not establish that this effect was the original design intent.
Pattern 3: central reset space
What helps users reorient when moving between zones with different purposes and behavioral norms?
Alternatives considered
- Direct connections between all spaces (creates jarring transitions)
- Isolated spaces with no visual connection (destroys wayfinding and orientation)
- Central hub with consistent behavioral baseline (allows smooth recalibration)
I read the Piazza Coperta as a reset point: a recurring, recognizable space from which users can reorient spatially and behaviorally.
Its visibility, central position and relatively stable sensory character make it a useful anchor between more specialized zones.
Trade-off: 'Reset' is an analytical model for the observed role of the atrium, not a measured cognitive state attributed to every visitor.
Implementation
Since this was research, the result is a set of analytical tools:
•Space → Sound → Practice model for comparing architecture, sensory cues and observed use
•Threshold taxonomy distinguishing rigid limits, gradual transitions and hybrid boundaries
•Acoustic ethnography workflow using recordings and spectrograms to make sound patterns inspectable
•Transfer notes connecting the findings to interface questions such as progressive disclosure, redundancy and state transitions
Outcomes & Impact
The research produced a vocabulary and a set of maps for discussing relationships that, in everyday experience of the space, are often perceived without being named. The work was then published in E|C, the journal of the Italian Association for Semiotic Studies.
14,000m² public space analyzed across three floors and multiple functional zones
45–50 dB difference documented between the loudest and quietest sampled zones
Identified recurring relationships between acoustic gradients, thresholds and observed behavioral shifts
Developed 'sensory rhyming' as a way to describe redundant cues across spatial and sensory channels
Separated planned spatial strategies from the tactics that emerge through everyday use
Connected semiotic frameworks to concrete UX questions without treating theory as evidence on its own
What I delivered
- Published ex-post analysis of Salaborsa's spatial, acoustic and behavioral system
- Space → Sound → Practice analytical model
- Acoustic ethnography and threshold-analysis method
- Transfer principles for physical and digital experience design
Reflections
Gradual thresholds are interesting because they let people adjust their behavior as they move, without a sharp boundary.
Semiotics was most useful to me for describing relationships I could observe on site.
What I would change
- Add systematic comparative observations across matched time windows and zones
- Compare Salaborsa with another multi-use civic space to test which patterns are specific and which generalize
What worked and what was difficult
What Worked
Different methods led to the same results
Spatial mapping, acoustic observation and semiotic analysis repeatedly converged on thresholds and gradients as the mechanisms organizing behavior.
Challenges
An ex-post analysis doesn't allow causal conclusions
The study can document recurring relationships between space, sound and practice, but it cannot prove that a specific design decision caused a specific behavior without an experimental comparison.
References
The theoretical references used for the semiotic analysis of space and the ex-post reading of Salaborsa.
1.de Certeau, M. (1980). The Practice of Everyday Life - Framework for strategies vs tactics in spatial appropriation
2.Greimas, A.J. (1976). Pour une sémiotique topologique - Semiotic analysis of space and isotopic coherence
3.Hall, E.T. (1966). The Hidden Dimension - Proxemics and culturally specific use of space
4.Hammad, M. (1983). L'espace comme sémiotique syncrétique - Multi-sensory spatial experience
5.Latour, B. (1987). Science in Action - Inscription devices for making phenomena visible
6.Lotman, J.M. (1985). On the Semiosphere - Space as primary modeling system
7.Lynch, K. (1960). The Image of the City - Imageability and spatial orientation
8.Zilberberg, C. (1993). Seuils, limites, valeurs - Distinction between thresholds and limits
Next project
Industrial HMI redesign