Façade Morphologies and Daylighting Strategies for Visual Comfort in Mediterranean Office Buildings: A Contextual Framework for Northern Cyprus

Abstract

The increasing adoption of highly glazed façades in contemporary office building has improved daylight penetration but has also intensified glare risk and sunlight overexposure in Mediterranean climates, with direct implications for occupant visual comfort and environmental sustainability. While daylight optimization has been widely discussed, fewer studies have examined how façade morphology systematically shapes the balance between daylight sufficiency and visual comfort in Mediterranean island contexts. This study investigates the relationship between façade configuration, daylight availability, and glare performance in office buildings in Northern Cyprus using climate-based daylight simulation. Six façade morphologies are evaluated across a range of window-to-wall ratios (WWR) using EN 17037-aligned criteria and metrics, including spatial daylight autonomy (sDA), annual sunlight exposure (ASE), and daylight glare probability (DGP). Usable daylight is not simply a function of more glass. As WWR increases, fully glazed façades in Mediterranean conditions tend to admit excessive direct sun and intensify glare, so daylight becomes less workable even when illuminance is high. Instead, hybrid and adaptive morphologies that control lighting through a combined approach of shade, diffusion, and redirection provide the most dependable performance, reducing both overexposure and glare while ensuring sufficient daylight sufficiency. The findings also indicate a distinct turning point at about 50–55% WWR, beyond which performance is mostly dependent on the façade’s ability to modulate its morphology and further glass offers minimal advantage. Based on this, the article suggests a contextual framework to encourage façade options for Mediterranean office environments that are more sustainable, aesthetically pleasing, and climate-responsive.

1. Introduction

In the workplace, daylight is a major factor in determining perceived spatial quality and visual comfort. Effective daylight design in offices may reduce operational energy consumption and promote environmental sustainability by enhancing visual task conditions, reinforcing circadian entrainment, and lowering dependency on electric lighting [1,2,3]. These benefits are challenging to achieve in high-solar Mediterranean regions, though, as frequent clear skies and extended periods of direct sunlight produce strong brightness contrasts and recurrent glare that, if not carefully managed, can offset the advantages of daylight [4,5].

Architectural openness has emerged as a defining characteristic of modern workplace architecture in addition to these performance goals [6]. However, excessive glazing can exacerbate visual discomfort and clash with local environmental conditions in Mediterranean environments, generating questions about the sustainability of the façade. This problem is particularly severe in Northern Cyprus, where a reflecting coastline setting and high atmospheric clarity can enhance glare exposure and lead to uneven illumination distribution throughout office interiors [4,7,8,9,10].

Building on this framework, the current study examines how façade morphology affects daylight performance and visual comfort in Northern Cyprus office buildings, with relevance to sustainable lighting design that minimizes unnecessary usage of electric lights while preserving acceptable inside conditions. The impacts of six sample façade solutions on spatial daylight autonomy (sDA), annual sunlight exposure (ASE), and daylight glare probability (DGP) are measured under local sky circumstances. In order to connect climate-based simulation outputs to a standardized performance framework, the analysis is organized according to the four EN 17037 daylight criteria: daylight provision, glare protection, exposure to sunlight, and view out [11]. In order to categorize the likelihood of discomfort under standard office viewing settings, glare results are evaluated using published DGP threshold values [12,13].

Grounded in prior research and informed by observations of regional office practice, the façade options are structured into three morphological families: Transparent and Direct Systems, Filtered and Diffusive Systems, and Responsive and Hybrid Systems. This grouping is based on how each façade primarily moderates daylight, whether by allowing largely direct transmission, introducing controlled diffusion and filtration, or using adaptive and light-redirecting configurations [14,15]. Morphology-based typologies of this kind are increasingly adopted to clarify the relationship between façade form and daylight autonomy and to explain variations in visual comfort under climate-specific conditions, with relevance to sustainable façade design.

To evaluate façade performance, the study employs three established simulation-based indicators, sDA, ASE, and DGP, representing useful daylight availability, the likelihood of sunlight overexposure, and glare-related discomfort, respectively [12,16]. The literature indicates that these metrics are well suited to distinguishing façade behaviour in high-solar climates, where daylight quality is strongly influenced by direct sun and pronounced luminance contrasts, making it necessary to consider daylight sufficiency alongside visual comfort [17,18,19]. In the present study, the climate-based metrics are used to translate the EN 17037 logic into measurable terms, supporting rather than substituting the standard’s criteria-based approach so that results can be interpreted consistently within its evaluation framework, and informing sustainability-oriented performance interpretation.

This study offers three integrated contributions to Mediterranean daylighting research. First, it proposes a morphology-based typology of six façade systems and explicitly links key geometric strategies, including transparency, filtering, layering, and adaptivity, to the performance logic and criteria structure of EN 17037 [11,14]. Second, it evaluates these morphologies within a Mediterranean island context where high solar altitudes, frequent clear-sky conditions, and coastal reflectance can intensify daylight exposure and glare risk compared with many continental settings [4,5]. Third, by combining climate-based daylight metrics (sDA, ASE, DGP) with a systematic variation in window-to-wall ratio, the study identifies a practical transparency threshold and demonstrates that façade morphology, rather than glazing area alone, governs the balance between daylight sufficiency, glare protection, and sunlight overexposure in office environments. When considered collectively, the results encourage more sustainable and environmentally friendly façade choices by giving priority to options that maximize daylight quality while minimizing visual discomfort and minimizing needless reliance on electric illumination.

The novelty of this study lies in an integrated, morphology-driven workflow that contributes EN 17037 criteria into climate-based performance metrics, while maintaining a tightly controlled parametric comparison across façade systems, contributing to sustainability-focused evaluation in Mediterranean office contexts. Instead of examining window to wall ratio or individual shading solutions as distinct variables, the research offers a unified approach that first creates a structured typology of façade morphologies, transparent and direct, filtered and diffusive, and responsive and hybrid, explicitly aligned with the EN 17037 performance components [11,14]. After that, it uses a methodical window-to-wall ratio sweep from 10% to 90% to find a key transparency region, around 50 to 55%, when penalties for glare and sun exposure increase significantly. Lastly, it provides a useful choice logic for Mediterranean office façades under island sky circumstances by creating a comparative performance hierarchy based on useable daylight, interpreting sDA together with limiting requirements for ASE and DGP.

Background of the Study

Workplace daylighting has a quantifiable impact on visual comfort, task performance, and overall user pleasure, according to a wealth of studies [1,2,20]. Climate-responsive daylighting can lower the need for electric lighting and related operational energy usage, improving the sustainability profile of office buildings, according to building-performance studies [3,21]. However, these benefits must be weighed against the higher risk of glare and direct sun penetration in Mediterranean climates, a problem that is frequently made worse in coastal island microclimates where high atmospheric clarity and surface reflectance amplify daylight extremes and luminance contrast [7,8].

In Northern Cyprus, many contemporary office buildings employ large glazed areas with minimal external modulation, which can lead to glare, overheating, and pronounced luminance contrasts across interior work zones [6]. Findings from comparable Mediterranean contexts likewise show that highly transparent façades, when not complemented by effective shading or filtering strategies, tend to increase annual sunlight exposure and glare probability, thereby reducing the usability of daylight even when overall illuminance levels are high [22,23,24,25].

Although a substantial body of work evaluates glazing properties, window to wall ratio, and discrete shading devices, fewer studies position façade morphology, including depth, layering, porosity, and geometric articulation, as the primary determinant of how daylight is transmitted, diffused, redirected, or blocked within office interiors [26]. With the wider adoption of parametric workflows, it is now possible to generate and test façade alternatives systematically under climate-specific conditions, yet integrative studies that connect EN 17037 criteria to clearly defined morphology typologies remain limited, particularly in Mediterranean island settings [11,27,28]. Existing simulation-based evidence indicates that even modest geometric adjustments can meaningfully shift outcomes for sDA, UDI, ASE, and DGP, and that multi-layer skins, porous screens, and hybrid systems can provide effective daylight modulation and glare mitigation in warm climates [12,21,27,29,30].

Despite these advances, relatively few studies integrate EN 17037’s criteria-based framework with the distinctive daylight conditions of Mediterranean islands and a clearly articulated set of façade morphology typologies within a single, coherent methodology. The practical need to link morphology-led classifications with climate-based daylight metrics to support more dependable performance interpretation and design decision-making is highlighted by documented concerns about visual discomfort in Northern Cyprus, which are frequently linked to excessive daylight penetration, inadequate shading, and limited façade modulation [31,32].

In order to close that gap, this work developed a structured façade morphology typology specifically designed for office buildings on Mediterranean islands and assessed its effectiveness using an interpretative methodology matched with EN 17037 and backed by climate-based simulation metrics [11,14,27]. The study offers an empirical basis and a conceptual justification for the methodological approach discussed in the next section by analyzing how different façade layouts affect daylight autonomy, glare probability, and sunlight exposure.

2. Materials and Methods

This study uses a mixed methods approach that combines simulation-based daylight analysis with a morphological review of representative façade systems. The methodological framework is organized into three interrelated phases. In the first phase, a morphological typology is defined that groups façade systems according to their mechanisms of daylight modulation.

In the second phase, parametric representations are created for each façade configuration, and climate-based daylight simulations are run under consistent boundary conditions. In the third phase, the performance of all configurations is assessed using internationally established daylight metrics interpreted within the framework of EN 17037:2019 Daylight in Buildings, which sets out the main criteria of daylight provision, glare control, exposure to sunlight, and view out. Climate based indicators, including sDA, ASE, and DGP are then applied to quantify these criteria in greater detail.

The methodology is designed to measure how different façade morphologies affect daylight availability, sunlight exposure, and glare risk under the climatic conditions of Northern Cyprus. To separate the impact of morphology from other factors, all simulations use identical parameter settings for every façade type.

2.1. Morphological Typology of Façade Systems

This research distinguishes three main groups of façade morphology. Each group includes two illustrative systems that represent different ways daylight interacts with the building envelope, from transparent, direct transmission to filtered, hybrid, and adaptive modes of modulation. Organizing the cases in this way allows performance to be compared systematically across contrasting geometric configurations. The typology is intended as a descriptive framework that illustrates the variety of morphological techniques employed in modern office design rather than as a rating of superior or worse solutions. Within this context, the distribution of daylight under Mediterranean solar circumstances is shaped by the spatial, environmental, and optical logic of each type of façade.

2.1.1. Category 1: Transparent and Direct Systems

Planar glazing façades are completely transparent enclosures that prioritize continuous views of the outside world and maximum lighting ingress. Because it provides minimum visual blockage and a strong sense of architectural simplicity, this style is often used in contemporary office architecture. In Mediterranean climates with intense solar exposure, however, such façades often generate very high illuminance (lx) levels close to the window, sharp luminance contrasts deeper in the room, and pronounced glare discomfort. Since daylight is admitted almost entirely through direct transmission, without built-in shading or redirection elements, the visual performance of planar glazing is strongly dependent on solar altitude, azimuth, and façade orientation. The reference window is a double-glazed low-e insulating glass unit (DG low-e IGU) with a visible transmittance of approximately (VT ≈ 80%+) and a solar heat gain coefficient of (SHGC ≈ 0.86), representing a common baseline glazing specification in contemporary Mediterranean office buildings.

Light shelves use a passive daylight redirection approach in which a horizontal reflective plane sends sunlight upward to the ceiling, which then redistributes it more evenly throughout the room. Light shelves provide useable daylight further into the room while reducing glare at eye level by directing light toward higher interior surfaces. Systems in this category nevertheless prioritize openness and transparency; instead of using heavy shading features, they mostly depend on direct transmission and mild light redirection.

2.1.2. Category 2: Filtered and Diffusive Systems

In front of the primary glass, perforated screens function as semi-transparent layers. By dispersing incoming sunshine, the arrangement of apertures reduces direct beam radiation and produces a softer, more diffuse interior light. This allows for some outward visibility while reducing glare and smoothing out brightness shifts. The optical performance of such systems is largely governed by aperture dimensions, overall porosity, and surface reflectance, which together determine how much daylight is filtered and how it is perceived indoors.

Fixed louvres offer static shading by means of horizontal or vertical blades that obstruct high angle solar rays. Their effectiveness depends on factors such as spacing, projection depth, surface reflectance, and orientation. While they can substantially cut direct solar gain, they are unable to adapt to seasonal shifts or daily changes in sun position. Taken together, the systems in this group act as stationary filters, limiting excessive sunlight by constraining geometric exposure rather than by actively redirecting incoming light.

2.1.3. Category 3: Responsive and Hybrid Systems

In contrast to the fixed systems, the adaptive and hybrid louvre façades are operated by the rule-based control strategy described in Section Control Strategy for Adaptive Louvre Façade. Hybrid façade systems bring together the reflective action of light shelves and the diffusing effect of perforated screens. In this layered arrangement, part of the incident sunlight is redirected deeper into the room while another part is softened and spread, which enhances spatial uniformity and lowers the risk of glare. By embedding several daylight control mechanisms within a single morphological configuration, hybrid façades are able to deliver a more balanced and comfortable luminous environment in high solar climates.

Since its slats may be reoriented in response to the location and intensity of the sun, adaptive louvres offer the most flexibility in controlling daylight. In actuality, they may modify penetration throughout the year, permit helpful light in cloudy or diffuse circumstances, and prevent direct radiation at peak hours. They are particularly appropriate for areas with significant solar fluctuation because of their dynamic behavior. Because of this, responsive louvre systems are an advanced level of façade development where environmental management and geometric configuration are purposefully integrated.

Control Strategy for Adaptive Louvre Façade

A simple rule-based solar control algorithm was used to mimic the adaptable louvre façade. In relation to the horizontal, the system functions in three distinct tilt states: totally open (≈0°), partially closed (≈30°), and considerably closed (≈60°). The yearly climate file is used to calculate the sun position and incident irradiance on the façade at each simulation timestep. The louvres remain completely open to maximize daylight penetration and preserve vision when the solar altitude is below (γ₁, e.g., 25°) or the façade is shaded. In order to minimize direct beam penetration while allowing diffuse daylight and maintaining outward visibility, the louvres transition to the partially closed condition for intermediate solar altitudes (γ₁–γ₂, e.g., 25–55°) under direct exposure. The louvres migrate to the mostly closed position, prioritizing glare control and restricting solar gains, when solar altitude reaches (γ₂, e.g., 55°) with direct exposure.

The control schedule was assessed using an hourly time step, consistent with the climate-based daylight simulations, and the selected louvre position was applied to all rays for that hour. This rule-based approach mirrors common operation in automated venetian or external louvre systems, where slat tilt is adjusted in response to solar height and exposure conditions. It also enables the daylight and glare performance of the adaptive façade to be compared and interpreted in a transparent and reproducible way.

This typological scheme highlights morphological variety rather than establishing a fixed hierarchy of performance. The selected façade systems were chosen because they are characteristic of contemporary office architecture and particularly relevant to Mediterranean climatic conditions. The typology builds on previous research into daylight redirection and façade performance [24,33,34,35].

All configurations are examined within the EN 17037:2019 framework, which specifies the key daylight criteria of provision, protection from glare, exposure to sunlight, and view out; in this study, these criteria are operationalized through established climate-based metrics.

Table 1. Morphological typology of the six façade systems examined in this study.

Morphological Category	Façade Models	Daylight Behaviour	Design Strategy & Performance Role	Visual Reference
1. Transparent and Direct Systems	Planar Glazing	Direct passage and mirror-like reflection of daylight, producing deep light penetration with a high risk of glare and pronounced luminance contrasts, especially in the zone adjacent to the façade.	High transparency and reflective surfaces reinforce a sense of openness and clear outward views. Light shelves increase daylight penetration by redirecting light onto the ceiling, but they still need to be paired with additional measures to ensure effective glare control.
	Light Shelves
2. Filtered and Diffusive Systems	Perforated Screens	Selective filtering of sunlight through openings or slats, producing softer, more diffuse interior light and moderate glare mitigation, but with limited capacity to respond to changing solar angles.	Static filtering of daylight, managing brightness and solar gains through the density, orientation, and porosity of the elements; most effective in contexts with relatively stable climatic conditions.
	Fixed louvres
3. Responsive and Hybrid Systems	Hybrid (Shelf + Screen)	Adaptive control of light and shade through a mix of redirection, diffusion, and shading, sustaining high daylight availability while curbing overexposure under changing sky conditions.	Adaptive integration uses a combination of reflection, diffusion, and movable elements to respond to solar conditions in real time, supporting stable daylight quality and visual comfort throughout the year.
	Adaptive louvres

summarizes the resulting classification, organizing six representative façade models into three groups according to their daylight interaction mechanisms and environmental performance strategies.

As summarized in Table 1, each model is assigned to its morphological category and briefly described in terms of expected daylight behaviour, the underlying environmental performance strategy, and the visual precedent used as a reference. The six façade archetypes were established through a targeted review of Mediterranean office façade design and a survey of relevant regional built examples, as outlined in Section 2.1.4.

Because the study relies on a complete factorial set of deterministic simulations rather than sampled field measurements, conventional inferential statistical tests, such as ANOVA or regression, intended to generalize from a sample to a wider population, were not necessary to confirm the numerical patterns. Instead, the influence of façade type and WWR was assessed by tracing how systematic changes in morphology and transparency alter the simulated metrics relative to EN 17037 targets and established discomfort thresholds, and by comparing the size of these shifts across all scenarios. The emphasis is therefore placed on practical significance, for example, whether a given configuration meets or exceeds recommended ranges for sDA, ASE, and DGP, rather than on probabilistic significance testing.

2.1.4. Derivation of Façade Morphology Typology

To define a façade morphology set that is both feasible for parametric simulation and reflective of common Mediterranean office practice, the study followed a three-step process. First, a focused review of daylighting and façade research in warm and Mediterranean climates was undertaken, with particular attention to side-lit office buildings assessed using climate-based metrics and EN 17037 related criteria. Across this literature, several recurrent strategies are repeatedly identified as prevalent and effective for balancing daylight provision with glare control and solar gain management, including planar glazing with limited external shading, horizontal light shelves, perforated metal screens, fixed horizontal louvres, and motorized venetian-type louvre systems.

Second, contemporary built examples in Northern Cyprus and neighbouring Mediterranean regions, including Cyprus, Greece, Turkey, and Spain, were examined through architectural documentation and field observations. This regional survey similarly showed that planar glazing, external light shelves, perforated screens, fixed louvres, and adaptive louvre systems appear consistently as dominant façade components in office buildings and mixed-use developments. Third, the recurring devices were consolidated into six archetypal morphologies, organised within three overarching daylight-control logics: Transparent and Direct Systems (planar glazing), Filtered and Diffusive Systems (light shelf, perforated screen, fixed louvres), and Responsive and Hybrid Systems (adaptive louvres, hybrid shelf plus screen). These archetypes are not intended as an exhaustive catalogue of all façade possibilities; rather, they represent a structured and comparable set that captures the main modes of daylight regulation, direct transmission, static filtering, and dynamic modulation, enabling consistent evaluation of daylight and visual comfort performance across scenarios

2.2. Parametric Modelling and Simulation

All façade configurations were generated and tested within a controlled parametric simulation environment to maintain consistency and reproducibility across the six morphologies. The models were built in Rhinoceros 3D, using Grasshopper as the parametric platform, and connected to the Radiance simulation engine through the Ladybug and Honeybee plugins.

Radiance Simulation Parameters and Convergence

Radiance-based simulations were conducted to generate climate-based illuminance and luminance distributions for the reference office. Radiance is a physically based backward ray-tracing engine that has been widely validated and applied in architectural lighting and daylighting research. In this study, Radiance was implemented via OpenStudio, which streamlines annual simulation workflows by handling sky model generation, daylight coefficient calculations, and post-processing of illuminance and DGP outputs. Radiance settings were defined in line with established recommendations for climate-based daylight simulations in office environments, with the aim of achieving an appropriate balance between numerical reliability and computational efficiency. The principal parameters used consistently across all simulation runs are listed in

Table 2. Radiance parameters used for annual daylight and glare simulations.

Parameter	Value	Description
-ab	2	Ambient bounces
-ad	2048	Number of ambient divisions
-as	256	Number of ambient super-samples
-ar	256	Ambient resolution (grid density)
-aa	0.2	Ambient accuracy
-lr	0.005	Limit for reflections
-lw	0.01	Ambient weight threshold

.

To confirm the numerical robustness of the selected settings, a convergence check was carried out for a representative subset of cases consisting of the south orientation at 50% WWR across all six façade morphologies. For these scenarios, ambient divisions and super-samples were doubled while the scene geometry was kept unchanged. Relative to the base configuration, the differences remained small, with sDA_300,50% varying by less than 2 percentage points, ASE_1000,250h by less than 1 percentage point, and DGP by less than 0.01. These results indicate that the adopted Radiance parameters provide stable daylight and glare outputs that are suitable for the comparative aims of the present analysis [36].

The whole simulation environment is summarized here to facilitate replication. Rhinoceros 8 was used for parametric modeling, and the simulation workflow was implemented using Grasshopper for climate-based luminance and illuminance calculations and the Ladybug 1.9.0 Tools ecosystem. The Nicosia Typical Meteorological Year (TMY2) climate file (hourly data) was utilized in annual simulations, which were assessed for a typical office schedule (08:00–17:00, Monday–Friday). In keeping with the study’s emphasis on frequently used job areas, Daylight Glare Probability (DGP) was calculated using Radiance (v6.0)-based brightness estimates at sample viewing locations matched with workstation placements in the furnished office module.

This simulation workflow is consistent with international best practice for climate-based daylight modelling and is commonly used in studies that reference EN 17037. The parametric setup enabled all façade variants, planar glazing, light shelves, perforated screens, fixed louvres, adaptive louvres, and hybrid systems, to be analyzed under the same spatial, climatic, and operational conditions. As a result, differences observed in daylight performance can be traced primarily to changes in façade morphology rather than to disparities in geometry or boundary conditions.

A generic office cell measuring 6.0 m × 6.0 m × 3.0 m served as the reference geometry for all simulations. Although EN 17037 does not fix room dimensions, this setup aligns with its evaluation logic, which focuses on daylight provision within the “useful daylight area” of a side-lit room. Under typical sky conditions, this area usually extends to a depth of about twice the window height. This depth represents a standard side-lit bay; deeper floor plates are addressed as a limitation and future extension. For a façade height of 3.0 m, a daylight reach of roughly 6.0 m is consistent with established daylighting research [30,37,38,39], and therefore provides a suitable basis for comparing performance across the different façade morphologies.

The study employs a standardized reference office module measuring 6.0 m in depth, 6.0 m in width, and 3.0 m in height, corresponding to a typical single-sided open-plan office bay frequently documented in daylighting literature and design guidance. This room size is widely used as a benchmark in simulation-based investigations of sDA, ASE, and DGP because it reproduces the characteristic daylight drop-off from the façade toward the rear of the space, while remaining efficient enough for extensive parametric testing. To keep the comparison focused on façade-related effects, the workplane definition and furniture arrangement were intentionally simplified and held constant across all façade scenarios, so that changes in daylight performance could be attributed mainly to façade morphology and window-to-wall ratio rather than to interior partitioning or highly specific fit-out conditions.

Although a single 6.0 m × 6.0 m × 3.0 m office module cannot represent the full diversity of contemporary workplace layouts, it offers a credible side-lit reference case that is consistent with EN 17037’s emphasis on evaluating daylight conditions within regularly occupied, useful areas. Prior simulation studies indicate that rooms with comparable proportions produce reliable trends in sDA, ASE, and DGP when façade parameters are varied, even if the absolute metric values can shift modestly with changes in depth or height. Accordingly, the findings of this study are intended to identify robust comparative differences among façade morphologies, rather than to provide fixed performance values applicable to every possible plan geometry. The potential influence of greater plan depths and alternative workplace configurations is therefore addressed in the limitations section and highlighted as an important direction for future research.

The chosen depth of 6.0 m represents the transition from the brightly lit zone adjacent to the façade to the gradually darker area at the rear of the room, allowing reliable assessment of spatial daylight autonomy, luminance gradients, and glare probability under Mediterranean sky conditions. The 6.0 m width corresponds to typical structural bay spans in contemporary Cypriot and wider Mediterranean office buildings, where ranges of about 5.5–6.0 m are frequently used. Every façade typology is evaluated against the same, architecturally accurate interior volume thanks to this breadth. Although the standard does not specify a precise room height, the interior height of 3.0 m represents typical office ceiling heights and supports EN 17037 assessments relating to sitting eye level, look out, and visual comfort.

In line with EN 17037:2019, all daylight calculations were referenced to a working plane at 0.85 m, representing the typical task height in office settings. This plane was used as the main evaluation surface for illuminance distribution and for deriving metrics such as spatial daylight autonomy (sDA_300,50%), annual sunlight exposure (ASE_1000,250h), and luminance-based indicators [9]. Although EN 17037 allows both illuminances based and climate-based assessment methods, using a consistent 0.85 m working plane secures ergonomic relevance and ensures methodological coherence across all daylight, glare, and visual comfort evaluations.

The reference model was first oriented due south, representing the most critical direction for Mediterranean latitudes, where solar altitude, beam intensity, and glare risk peak during standard office hours. To reflect the fact that real buildings rarely align exactly with the cardinal axes, additional simulations were carried out with the model rotated plus and minus sixteen degrees, a deviation that corresponds to the prevailing north south building grid in Lefkosa (Nicosia), where most façades therefore face east or west, a pattern rooted in historical practice that seeks to capture morning sun while limiting harsh afternoon exposure [40].

EN 17037 also recommends testing daylight robustness across angular variations of about ten to twenty degrees, since even small orientation changes can significantly affect solar penetration, shading behaviour, and glare potential; including the plus and minus sixteen-degree cases, therefore enhances climatic realism and increases the applicability of the findings to diverse urban site conditions in Northern Cyprus. Interior layout and task placement were designed to align with EN 17037’s focus on evaluating daylight in furnished, actively used spaces. The open-plan layout of the reference office cell’s four workstations is typical of modern Cypriot offices. This configuration guarantees that indications of glare danger and daylight adequacy are evaluated accurately at locations where occupants have the highest visual demands and are most susceptible to luminance discomfort.

The Typical Meteorological Year (TMY2) climate dataset for Nicosia, which offers hourly values for solar altitude, radiation, and sky brightness, was utilized in daylight simulations. A normal office schedule from 8:00 to 17:00, Monday through Friday, which represents average administrative work patterns in Northern Cyprus, was the subject of annual climate-based research. In order to provide reliable, luminance-based glare assessment, radiance was used as the primary engine for illuminance and luminance computations, with parameters adjusted to high precision. When combined, the simulation tools and climate file offer a reliable and transparent procedure that aligns with accepted daylighting research methodology.

Performance assessment was conceptually aligned with the four components defined in EN 17037, daylight provision, glare protection, sunlight exposure, and view out, which together form the overarching framework for daylight quality. In the present simulation study, however, only the first three components were quantified through climate-based metrics, while view out was treated as a qualitative, conceptual criterion. Spatial Daylight Autonomy (sDA_300,50%) was used to evaluate daylight sufficiency across the working plane, Annual Sunlight Exposure (ASE_1000,250h) was used to locate zones prone to excessive illuminance and overexposure, and Daylight Glare Probability (DGP), the glare index endorsed by EN 17037, quantified visual discomfort at selected viewing positions. Explicit geometric evaluation of view out (for example, sky visibility, horizontal viewing angle, and depth of external reference layers) was not performed because the focus of the simulations was the internal behaviour of a generic office module rather than site-specific external views.

EN 17037 establishes a performance-based structure for daylight evaluation through four criteria: daylight provision, glare protection, exposure to sunlight, and view out [11]. In this study, the framework is implemented by using climate-based metrics to quantify the first three criteria in a consistent manner. Daylight sufficiency is assessed using sDA_300,50%, annual sunlight overexposure is captured through ASE_1000,250h, and glare risk is evaluated using DGP, the luminance-based glare index referenced within the EN 17037 approach [11,14]. Glare results are interpreted against widely adopted DGP threshold ranges reported in established glare research [12,16]. For sunlight exposure, EN 17037 defines the metric as the duration of direct sunlight reaching the interior on a reference winter day; although no compulsory numerical limit is imposed, the standard provides indicative performance bands of 1.5, 3, and 4 h as guidance [11,20,41]. View out is retained as a formal EN 17037 criterion, but it is not quantified here because the simulations are based on a generic office module and do not include the site-specific external context required for geometric view evaluation [11] (Figure 1).

Table 3. Simulation Parameters Aligned with EN 17037.

Window-to-Wall Ratio (WWR)	10–90%, 10% increments. EN 17037 does not prescribe WWR; performance is evaluated through daylight/glare criteria.
Glazing Type	Double low-e coated IGU. Not mandated by EN 17037; selected to support daylight provision and glare control in warm Mediterranean climates.
Visible Light Transmittance	0.45. A material property (not an EN requirement); chosen to balance daylight levels and reduce glare in high-solar conditions.
Orientation	South, rotated 16°. EN 17037 allows realistic site orientation; rotation reflects typical urban alignment in Northern Cyprus.
Simulation Period	08:00–17:00 (Mon–Fri). Aligned with EN 17037 Annex A for standard office occupancy hours.
Weather Data	Nicosia Typical Meteorological Year (TMY2). Suitable for climate-based daylight assessment consistent with EN 17037 performance principles.

summarizes the simulation parameters applied to all façade morphologies. The chosen WWR range, glazing specification, and visible light transmittance are not directly prescribed by EN 17037, but were selected to enable a robust assessment of daylight and glare performance under Mediterranean climatic conditions. The predominantly south facing orientation with a 16° rotation reflects common building alignment in Northern Cyprus, while the occupancy schedule and Nicosia TMY2 climate file ensure that daylight behaviour is evaluated for typical office hours. Together, these settings establish a consistent, EN 17037 aligned basis for comparing daylight performance across the six façade configurations.

Daylight penetration, luminance contrast, and solar gain are all significantly impacted by the Window to Wall Ratio (WWR), which is why it was chosen as a critical variable. Ten WWR levels were tried in order to capture a subtle gradient of façade transparency: 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90%. Compared to methods that classify WWR into just broad low, medium, or high categories, this fine resolution enables a more accurate analysis of daytime behavior.

Many daylighting studies in warm regions show that mid-range transparency (around 20–40%) frequently offers a suitable balance between daylight adequacy and visual comfort, even though EN 17037 does not specify precise glazing ratios [4,5,33,34,42]. This study investigates performance at lower and higher transparency levels that are often overlooked, in addition to this generally successful mid band, by expanding the investigation to 10 different WWR steps. Taking into account the entire spectrum guarantees that the comparison of the six façade morphologies is comprehensive, internally consistent, and sensitive to Mediterranean climate conditions, supporting EN 17037’s performance-based rationale.

The four primary elements of EN 17037, daylight provision, glare prevention, sunlight exposure, and view out, which collectively provide a consistent European framework for evaluating daylight quality, were followed in the daylight performance analysis. The standard’s performance-focused approach is consistent with the extra indications employed in this study, even though it does not require specific climate-based measurements. Accordingly, climate-based measures such as sDA_300,50% and ASE_1000,250h were used to complement the EN 17037 criteria, providing finer quantification of daylight sufficiency and potential overexposure under Mediterranean conditions.

EN 17037 defines sunlight exposure as the length of time that direct sun reaches a space on a reference winter day. Although the standard itself does not stipulate fixed numerical limits, several national annexes and academic commentaries propose indicative ranges for minimum, medium, and high performance. The British version, BS EN 17037:2018, includes in its informative Table A.6 approximate thresholds of 1.5 h for minimum, 3 h for medium, and 4 h for high performance on the reference day [11]. Comparable values are reported in Phan’s [20] technical summary and by Hraška et al. [41], both of which adopt the same 1.5–3–4 h structure when classifying sunlight exposure. While these thresholds are not mandatory, they provide a useful benchmark for balancing the benefits of solar access against the risks of overheating and visual discomfort.

Glare protection was evaluated using Daylight Glare Probability (DGP), a luminance-based index recommended in EN 17037 for assessing visual discomfort. Although the standard does not define numerical classes, commonly used thresholds from Wienold and Christoffersen designate DGP values below 0.35 as imperceptible, between 0.35 and 0.40 as perceptible but generally acceptable, and above 0.45 as disturbing [12]. These ranges continue to provide the most reliable basis for interpreting glare performance in daylit interiors.

View out, as defined in EN 17037, denotes the quality of the visual connection between interior spaces and the outdoor environment, evaluated from representative reference points within the utilized area. A satisfactory view should be clear, undistorted and neutrally coloured, and ideally encompass three layers of information: sky, landscape and ground. The standard characterizes the view out through three geometric parameters: horizontal sight angle, viewing distance and the number of visible layers. Informative guidance in BS EN 17037:2018 distinguishes three indicative performance levels, with minimum view out achieved at approximately 14° horizontal sight angle, 6 m viewing distance and at least one (landscape) layer; medium performance at about 28° sight angle, 20 m distance and two visible layers; and high performance at around 54° sight angle, 50 m distance and all three layers present [11].

These graded levels relate façade design to occupants’ access to environmental information, thereby supporting visual comfort, spatial orientation and psychological well-being (Table 2). Simulation reliability was ensured through careful calibration of Radiance parameters, convergence testing, and cross-checking of metric stability across all morphological scenarios. Variations in sDA, ASE, and DGP were confirmed to stay within permissible bounds for Mediterranean climate conditions by internal consistency tests. The study creates a rational, climate-specific, and methodologically sound framework for evaluating daylight adequacy, glare management, and general visual comfort in modern office buildings by fusing recognized climate-based metrics with EN 17037 performance criteria.

Figure 2 summarizes the methodological procedure that the study adheres to. The six façade morphologies are divided into three groups in Step 1: Responsive and Hybrid Systems, Filtered and Diffusive Systems, and Transparent and Direct Systems. The base geometry definition, the daylight simulation setup, the iterative façade geometry development, and the final simulation runs are all covered in Step 2 of the parametric modeling process created in Rhino and Grasshopper. In accordance with EN 17037 (Daylight in Buildings), Step 3’s evaluation stage involves the assessment and interpretation of Spatial Daylight Autonomy (sDA_300,50%), Daylight Glare Probability (DGP), and Annual Sunlight Exposure (ASE_1000,250h) (Figure 2).

3. Results

The outcomes of the climate-based simulations are presented in this section. Using three complementary indicators, Spatial Daylight Autonomy (sDA) to describe daylight sufficiency, Annual Sunlight Exposure (ASE) to identify potential overexposure, and Daylight Glare Probability (DGP) to quantify visual discomfort, the analysis looks at how the six façade morphologies perform across Window to Wall Ratios (WWR) from 10% to 90%. When combined, these measurements show how transparency, sun management, and visual comfort are traded off under Mediterranean sky circumstances.

Spatial Daylight Autonomy (sDA_300,50%) for WWR values from ranging 10% to 90% is plotted across all six façade morphologies in Figure 3. Although sDA typically rises with WWR across the matrix, the rate and quality of this increase differ depending on the kind of façade. Even mid-range transparency may provide enough daylight in this environment, as seen by the high daylight sufficiency achieved by planar glazing, hybrid (shelf + screen), and adaptive louvres, which attain sDA values above around 70–80% from roughly 40–50% WWR onwards.

Light shelves exhibit a similar rising tendency, with a discernible increase at 60% WWR as ceiling reflections improve. Although they still reach the 50–60% range at greater transparencies, fixed louvres and perforated screens offer more modest autonomy levels, particularly at lower WWRs. On the whole, the heatmap indicates that although larger apertures tend to improve sDA, the improvement is not linear: morphological differences are most noticeable in the mid-range (30–60% WWR), highlighting the fact that façade configuration, rather than just glazing area, is a crucial factor in determining daylight sufficiency (Figure 3).

The distribution of Daylight Glare Probability (DGP) for all façade shapes and WWR values is shown in Figure 4. Planar glazing routinely records the highest glare values, with DGP usually falling between 0.40 and 0.48 and often falling within Wienold and Christoffersen’s “perceptible to disturbing” category. Light Shelf layouts perform mediocrely: DGP values stay near 0.30 at smaller WWRs but climb toward 0.35–0.39 as transparency rises, suggesting a rising discomfort risk at bigger apertures. Although they provide little protection at the highest WWRs, perforated screens and fixed louvres maintain mid-range glare levels (about 0.29–0.36), usually within the “perceptible but acceptable” region. The majority of circumstances are kept within the “imperceptible to just perceptible” range across all WWRs by hybrid (Shelf + Screen) and adaptive louvres, which have the lowest DGP values overall (about 0.22–0.31). When combined, the findings demonstrate that the use of efficient modulation techniques that disperse, deflect, or dynamically manage incident sunlight has a greater influence on glare risk than window size alone (Figure 4).

Figure 5 presents Annual Sunlight Exposure (ASE_1000,250h) for all façade morphologies across WWR values from 10% to 90%. Planar Glazing exhibits the highest levels of overexposure, with ASE rising from about 12% at 10% WWR to nearly 38% at 90%, clearly indicating a strong risk of oversupply of direct sun. Light Shelf, Perforated Screen, and Fixed louvre systems form a middle band of performance, generally ranging between roughly 8% and 20% depending on transparency, with a gradual increase in overexposed area at larger apertures. In contrast, Hybrid (Shelf + Screen) and Adaptive louvre façades provide the most effective solar control, maintaining ASE mostly within the 5–14% range even at higher WWRs. Taken together, the results show that layered and responsive morphologies can substantially suppress problematic overexposure compared with unshaded planar glazing, achieving lower ASE values without eliminating useful daylight.

When sDA, ASE, and DGP are considered together, Hybrid (Shelf + Screen) and Adaptive louvre systems provide the most balanced daylight performance. They combine high daylight sufficiency (sDA rising into the upper 70–80% range at mid-to-high WWRs) with low overexposure (ASE generally below about 15%) and the lowest DGP values in the sample (approximately 0.22–0.31), corresponding largely to imperceptible or just-perceptible glare. Light Shelves achieve comparatively high sDA at larger WWRs, but this gain is accompanied by increasing ASE and DGP, indicating a growing risk of discomfort under intense solar exposure.

Perforated Screens and Fixed louvres show intermediate behaviour, effectively moderating glare and overexposure but delivering only moderate sDA, particularly at lower WWRs. Planar Glazing, although capable of high sDA at large glazing ratios, exhibits the weakest overall performance due to substantial overexposure (ASE approaching 40%) and consistently elevated DGP values in the perceptible-to-disturbing range. Taken together, these findings reinforce that façade geometry, layering, and adaptability exert a stronger influence on visual comfort than window size alone (Figure 5).

Figure 6 synthesizes the combined behaviour of the six façade morphologies by overlaying sDA, DGP, and ASE across the full WWR range. The last (fourth) layer of the integration of the three layers ranking shows a clear hierarchy. Hybrid (Shelf + Screen) and Adaptive louvres occupy the top tier, consistently combining high daylight autonomy with low overexposure and low glare across all WWRs. Their layered and/or responsive geometries enable them to admit sufficient daylight while modulating direct sun, so comfort is maintained even as transparency increases.

A second tier is formed by the Light Shelf, Perforated Screen, and Fixed louvre systems. These façades deliver broadly acceptable performance, but each has limitations: Light Shelves achieve strong sDA yet tend toward higher ASE and DGP at large WWRs; Perforated Screens provide stable, diffuse daylight with moderate sDA; Fixed louvres maintain acceptable ASE but cannot prevent glare escalation at higher glazing ratios due to their static configuration. Planar Glazing is clearly the weakest performer, with rising ASE and persistently high DGP as WWR increases, indicating widespread glare and overexposure despite improved sDA. Overall, Figure 7 confirms that façade morphology, particularly layering and adaptivity, has a more decisive impact on visual comfort than window size alone, and that simply increasing transparency is insufficient for Mediterranean office conditions without effective modulation of incident daylight annual (Figure 6).

The results are summarised by assigning each façade a rank from 1 (best) to 6 (worst) across the three key performance metrics. The sDA_300,50% row captures daylight sufficiency, where higher values indicate a larger share of the working plane achieving the daylight target. The DGP row reflects glare risk, with lower DGP values indicating better visual comfort. The ASE_1000,250h row represents annual sunlight overexposure, where lower ASE values indicate stronger protection against excessive direct sun (Figure 7).

Taken as a whole, the three rows reveal a clear trade off between daylight quantity and visual comfort. Façades that perform strongly in sDA_300,50% are not always the most comfortable solutions. Perforated Screens, Fixed Louvres, and Light Shelves achieve the highest ranks for sDA, indicating effective daylight provision, yet their rankings decline for DGP and or ASE_1000,250h. This indicates that a portion of the daylight benefit is accompanied by increased glare likelihood and greater sunlight overexposure at certain window to wall ratios. By contrast, Planar Glazing consistently performs worst, especially for DGP and ASE_1000,250h, reinforcing that an unmodulated fully glazed façade carries the greatest risk of glare and overexposure under Mediterranean sky conditions, even when overall daylight levels appear high.

In contrast, the Hybrid (Shelf + Screen) and Adaptive louvre systems achieve the strongest rankings for both DGP and ASE_1000,250h, indicating the most consistent control of glare and direct sunlight. While their sDA_300,50% ranking is not the highest, their stable comfort performance across metrics suggests the most balanced overall behaviour. In terms of functionality, these geometries promote useable sunshine while significantly lowering the risk of visual discomfort and solar overexposure, which is in line with the demands of modern Mediterranean office spaces for visual comfort. When combined, the comparative ranking emphasizes the main conclusion of the study: façade shape and its capacity to control incoming light through layering, dispersion, and adaptivity are more important for visual comfort than glazing area alone (Figure 7).

In addition to the metrics, the various façade types differ in how each system affects indoor brightness patterns, contrast ratios, and the amount of direct solar penetration. Planar glass concentrates brightness close to the façade and sharply reduces lighting toward the back of the space since daylight enters mostly through direct transmission. When WWR is increased, a larger portion of the visual field is occupied by the bright sky, which raises luminance contrast and increases DGP, while also allowing more direct sunlight to reach the workplane. As a result, fully glazed façades may score highly in sDA_300,50% but still exhibit unacceptable ASE_1000,250h levels and glare conditions.

The filtered and diffusive systems (light shelf, perforated screen and fixed louvres) moderate this behaviour by partially intercepting and redirecting sunlight. Light shelves project daylight onto the ceiling, increasing the proportion of indirect light and smoothing the front–back gradient, while perforated screens and fixed louvres break up direct beam components into smaller luminous patches and reduce peak luminance’s at the window. Consequently, these systems still provide adequate daylight autonomy at moderate WWRs but with lower ASE and DGP than planar glazing.

Responsive systems introduce an additional level of refinement by actively adjusting to changing solar exposure. In the adaptive louvre and hybrid shelf–screen configurations, the elements tilt or work in combination to block or redirect direct sun when it would otherwise produce high-intensity brightness within the occupant’s field of view, while remaining more open under diffuse sky conditions or at less critical sun angles. Strong levels of diffuse daylight on the work plane are supported by this time-responsive modulation, which also aids in preserving a more uniform brightness distribution across the interior picture. These processes account for the morphologies’ ability to maintain consistently low ASE_1000,250h and DGP over the studied WWR range while achieving high sDA_300,50%.

In total, the results show that window to wall ratio and façade form strongly interact. While most systems yield generally similar results for sDA_300,50%, at low to mid-range WWR values of 10 to 50%, distinct variances are already apparent for DGP and ASE_1000,250h. In this range, planar glazing frequently exceeds discomfort thresholds, whereas the hybrid and adaptive solutions generally remain within acceptable limits. Once WWR rises beyond roughly 50 to 55%, the divergence becomes more pronounced. Planar glazing shows concurrent increases in ASE_1000,250h and DGP, pushing many cases into clearly unacceptable performance zones. By contrast, adaptive louvres and the hybrid shelf–screen configuration tend to keep sDA_300,50% at or above recommended targets while holding ASE_1000,250h and DGP close to, or below, their respective limits. These differences therefore reflect systematic shifts in performance relative to EN 17037 criteria for daylight provision, glare protection, and exposure to sunlight, rather than being merely visual patterns in the heatmaps.

An integrated plot is included to complement the heatmap matrices and to make the relationships among sDA_300,50%, ASE_1000,250h, and DGP easier to read as a single performance profile (Figure 8). WWR = 50% was chosen because it is within the key transparency range (about 50–55%) found in the present research, where overexposure to sunlight and glare risk start to rise significantly. The comparative hierarchy across façade morphologies stays constant throughout the studied WWR range, with performance separation becoming more noticeable beyond the defined threshold, hence the qualitative results are unaffected by this particular decision. The ranking and heatmap findings additionally show that the comparative hierarchy across façade morphologies is consistent throughout the evaluated WWR range.

Using WWR = 50% as a representative reference point, each metric was normalised so that larger values indicate better overall performance, meaning stronger daylight sufficiency together with lower glare likelihood and reduced sunlight overexposure. The resulting radar chart makes the trade-off immediately visible. Planar glazing produces a highly distorted profile, driven by strong sDA_300,50% but weak scores on the comfort-related axes, reflecting elevated ASE_1000,250h and DGP. By comparison, the hybrid and adaptive solutions form tighter, more evenly distributed shapes, indicating consistently favourable outcomes across all three metrics. The light shelf, perforated screen, and fixed louvre options sit between these two patterns, confirming that they moderate glare and exposure relative to planar glazing but do not achieve the same level of balance as the responsive morphologies.

Figure 8 integrated comparison of the trade-offs between daylight sufficiency, glare risk, and sunlight overexposure for the six façade morphologies at WWR = 50% as a sample. All metrics are scaled to a 0 to 1 range, where higher values represent stronger overall performance, meaning higher sDA_300,50% together with lower ASE_1000,250h and lower DGP. The plot shows that the hybrid and adaptive solutions maintain the most even profile across the three criteria, outperforming planar glazing and the purely static façade options in terms of balanced daylight and comfort behavior (Figure 8).

4. Discussion

The findings of this study confirm that façade morphology is a decisive determinant of daylight performance and visual comfort in Mediterranean office buildings. Increased Window-to-Wall Ratio (WWR) does not, by itself, provide improved daylight conditions in all scenarios. Rather, whether more glazing area results in useful daylight or in discomfort and overexposure depends on how the façade regulates, reroutes, or filters incoming radiation. The comparison findings show a distinct difference between responsive or hybrid designs and transparent/direct solutions. Despite providing the highest level of transparency, planar glazing typically yields the least favorable results in terms of visual comfort. Even while sDA values climb in tandem with WWR, ASE and DGP also sharply increase, especially beyond mid-range glazing ratios. In actuality, a significant portion of the incident daylight is rendered useless due to the inhabitants’ exposure to unsettling glare and extensive over-illumination. This supports other studies showing that large glass façades in high-solar climes never provide satisfactory comfort without significant modification [33,34,43].

In contrast, Hybrid (Shelf + Screen) and Adaptive louvre systems maintain ASE and DGP within acceptable boundaries over the whole WWR spectrum while consistently achieving high levels of daylight autonomy. Their efficiency is not due to any one technology, but rather to the combination of complementary processes, diffusion, shade, and reflection. The hybrid façade creates a steady, consistent lighting environment by passively rerouting light via shelves and softening it through perforated layers. Similar results are obtained by adaptive louvres, which also have the ability to react to shifting sun angles, lowering exposure peaks during crucial periods of the day. When taken as a whole, these systems represent a change from transparency-led design to façades thought of as environmental interfaces that actively mediate between interior usage and sky conditions.

Systems that are diffusive and filtered occupy a middle ground. Particularly at mid-range WWRs, perforated screens and fixed louvres successfully reduce solar gains and decrease glare. However, their capacity to adapt to daily or seasonal fluctuation is limited by their static geometries. Although perforated screens offer strong ASE control and respectable DGP values, their sDA is still modest, particularly at lower glazing ratios. On the other hand, fixed louvres often maintain adequate ASE while providing only minimal glare protection and daylight sufficiency at high WWRs. Light shelves are likewise in this second rank; their glare and overexposure rates increase as they acquire more transparency, but they perform well in terms of sDA at medium and large WWRs due to greater ceiling reflection. All of these findings point to the fact that while single-function systems may handle one or two elements of daytime performance, they are unable to concurrently balance all four EN 17037 requirements.

For design practice, the WWR threshold found in the results is very crucial. Performance advances with increasing WWR for all morphologies up to around 50–55%; after that, ASE and DGP grow more quickly than sDA. More window space at greater glazing ratios mostly increases direct sun penetration rather than adding to usable daylight. Only systems with substantial modulation capability, like hybrid or adaptive façades, can maintain acceptable comfort in this upper range, when façade form becomes the dominating control variable. These results contradict long-standing formal preferences for highly glazed façades and provide credence to the growing body of research in Mediterranean daylight literature that suggests moderate transparency, when paired with efficient shade and redirection, offers more reliable performance than extreme glazing.

Important trade-offs between daylight, glare, and view out are also shown by the study presented by EN 17037. Perforated screens and, to a lesser extent, fixed louvres are examples of filtered systems that provide effective control over ASE and DGP. However, because they reduce horizontal sight angle and attenuate visual detail in the external scene, they may partially degrade view quality. By maintaining comparatively large, readable perspectives while still changing light, hybrid and adaptive systems reduce this strain. In office settings, where orientation, psychological health, and perceived environmental quality are all influenced by a link to the outside world, this balance is crucial. The findings thus support EN 17037’s focus on looking out as an integral part of visual comfort as opposed to a secondary aesthetic concern.

One important constraint of this study is that the entire simulation set is built around a single side-lit reference office measuring 6.0 m × 6.0 m × 3.0 m, with a fixed and deliberately simplified furniture arrangement. Since climate-based daylight indicators such as sDA, ASE, and DGP depend on spatial geometry, the absolute metric values would be expected to change if the room depth, ceiling height, or internal subdivision were substantially modified. Even so, the comparative patterns remain meaningful. Across all tested window-to-wall ratios, the relative ordering of façade morphologies was stable for daylight sufficiency, glare risk, and sunlight overexposure, with hybrid and adaptive systems consistently performing better than planar glazing and purely static options. Accordingly, the findings should be read as evidence of robust relative behaviour among façade archetypes under Mediterranean daylight conditions, rather than as precise predictions for every office layout. Further research should therefore examine deeper and multi-bay configurations and investigate how façade morphology interacts with more complex furniture layouts and partition strategies.

The reference case used in this study reflects a single-sided, side-lit office bay with a depth of 6 m. In practice, however, many contemporary offices are organised around deeper floor plates, typically in the range of 8 to 12 m, where daylight admitted through the façade has a weaker influence on the rear zone. Under such conditions, spatial daylight autonomy would be expected to decline toward the back of the plan as daylight penetration reduces, which in turn can increase dependence on electric lighting in deeper work areas. At the perimeter, by contrast, glare risk and direct-sun overexposure are likely to remain significant, because these outcomes are driven mainly by luminance contrast at the façade and the extent of direct solar penetration near the window. Accordingly, while increasing depth and changing workstation locations may shift the absolute values of sDA, ASE, and DGP, the relative reading of façade morphologies as daylight modulators, in which layered, diffusive, and adaptive systems outperform unmodulated planar glazing, is expected to remain broadly consistent.

Future work should therefore evaluate deeper and multi-bay configurations to quantify this sensitivity and to extend the applicability of the framework to larger floor-plate typologies. Future research could build on the present simulation framework by incorporating formal global sensitivity analysis or regression-based modelling, enabling a more systematic quantification of how façade parameters, window-to-wall ratio, and room geometry each contribute to variations in daylight and glare outcomes.

Furthermore, the study focused primarily on visual comfort as expressed through daylight provision, glare protection, and sunlight exposure and did not include a full quantitative evaluation of the view-out component of EN 17037. Because the simulation model represents a generic interior module without a site-specific external context, geometric indicators of view out (such as visible sky fraction, viewing distance, and depth of external reference layers) were not calculated and were instead discussed qualitatively in relation to each façade morphology. This omission means that the external visual connection is only partially represented and should be addressed through dedicated view-out analyses in future work. Finally, the study did not evaluate thermal impacts or overall energy demand, even though solar gains strongly influence cooling loads in Mediterranean climates. Future research should extend the morphological framework to a wider set of building typologies and orientations, investigate coupled daylight–thermal performance, and test more complex control logics and user responses.

Another constraint of the present analysis is that it adopts a single glazing specification, namely a double-glazed low-e unit with fixed optical properties. In practice, Mediterranean office façades often employ a broader range of solar-control glazing solutions, such as spectrally selective coatings, reflective or tinted glass, and electrochromic systems. These alternatives can substantially moderate solar heat gains and peak interior illuminances while preserving daylight admission and outward view, and prior research indicates that they can improve thermal comfort and lower cooling energy demand relative to conventional low-e glazing in warm climates, thereby supporting operational energy efficiency and building sustainability objectives [44,45,46].

If alternative glazing systems were adopted, the absolute ASE and DGP values reported in this study would likely be lower, especially for planar glazing and lightly shaded configurations, while sDA would be expected to decrease to a more moderate extent. Even so, the overall ordering of façade morphologies is likely to remain largely unchanged, because the fundamental daylight-control logics, direct transmission, static filtering, and dynamic modulation, do not depend on any single glass transmittance value. For this reason, a systematic evaluation that combines façade morphology with different solar-control glazing specifications represents a clear and important direction for future research.

On the whole, the discussion highlights a key finding: in Mediterranean island settings, the most important factor is not the quantity of glass a façade contains, but rather how well it controls the amount of sunshine that enters. A fundamental design lever for balancing daylight provision, glare prevention, sunlight exposure, and view out within a single, cohesive framework is façade morphology, especially when articulated through layered, diffusive, and adaptable techniques.

5. Conclusions

The present investigation looked at the effects of six façade morphologies on daylight performance and visual comfort in Mediterranean office buildings, arranged into three typological groups. The study focused on a prototype office module in Northern Cyprus and methodically altered WWR from 10% to 90% using EN 17037 as the evaluation framework and climate-based metrics (sDA, ASE, DGP) as quantitative indicators. The findings show that the balance between daylight adequacy, glare control, and solar exposure is determined by façade shape rather than glass space alone, with obvious implications for environmentally sustainable office architecture.

There are three primary conclusions that may be made. First, without enough modulation, totally glass façades are inappropriate for Mediterranean office environments. Particularly at large WWRs, Planar Glazing consistently delivered only usable sDA combined with significant ASE and DGP values. These results support the idea that “more glass” does not translate into improved lighting quality; rather, excessive transparency increases glare and overexposure, impairing comfort and energy efficiency as well as the sustainability of buildings as a whole.

Second, Hybrid (Shelf + Screen) and Adaptive louvre systems emerged as the most successful strategies. Across the entire WWR spectrum, these façades achieved high spatial daylight autonomy while maintaining low levels of overexposure and glare. Their layered and/or dynamic geometries make it possible to admit abundant daylight, redirect it to deeper zones, and attenuate direct sun when necessary. In effect, they operationalize the performance intentions of EN 17037 by simultaneously addressing daylight provision, protection from glare, and sunlight exposure, and by remaining compatible with high-quality view-out conditions, even though explicit geometric evaluation of view out lay beyond the scope of this study. The study therefore supports a design shift towards façades that combine reflection, diffusion, and adaptive shading within a coherent morphological framework.

Third, the analysis identifies a practical WWR threshold of approximately 50–55%. Up to this range, increases in glazing area tend to improve daylight access across morphologies. Beyond it, ASE and DGP escalate disproportionately, and only façades with strong modulation capacity can preserve acceptable comfort. In Mediterranean office buildings, very high glazing ratios should only be taken into consideration if they are paired with strong hybrid or adaptable façade systems. This threshold contradicts current glass-box design trends and offers a specific guideline for early-stage decision-making.

By redefining the façade as a performative environmental interface, the research also makes a conceptual contribution. The findings highlight façades’ function as dynamic mediators of temperature, light, and human experience rather than interpreting them as static, image-driven surfaces. Façades may promote visual comfort, lessen the need for artificial lighting, and more accurately match the climatic conditions of Mediterranean island environments when reflecting, diffusive, and adaptable features are used from the beginning.

The methodological approach and important findings offer a basis for future research, even if the study is based on controlled simulations and a single representative office type. Future studies should include thermal and energy evaluations, investigate real-world control mechanisms and user reactions, and expand the morphological categorization to include a variety of building shapes and orientations. These expansions would aid in converting the current findings into thorough design recommendations and legal backing.

In conclusion, the study suggests that façades that emphasize modulation, layering, and adaptability should replace transparency-driven enclosures in Mediterranean office architecture. Architects, interior architects and designers can create workspaces that are not only aesthetically pleasing and energy-efficient, but also sustainable and more sensitive to the environmental and experiential conditions of Mediterranean island contexts by implementing climate-responsive morphological strategies, such as hybrid systems and adaptive louvres.