A. Luna Navarro
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56 records found
1
Interface design for lighting and shading controls
Device type, position, and system cues influencing user preference and acceptance
Journal article
(2026)
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P. de la Barra, P. Martinez-Alcaraz, E. Brembilla, G. Brager, K. Exss, A. Luna-Navarro
The integration of smart control systems in office buildings can be disruptive when individual preferences and expectations for control interfaces are overlooked. Understanding how human–building interaction influences environmental comfort and acceptance is essential for creating user-centered designs. This study aimed to evaluate the effectiveness of usability testing as an innovative method for assessing building system control interfaces and user interaction with automation. Specifically, we examined user preferences for shading and lighting controls in a controlled office laboratory, varying by “Type of Device” (analog vs. digital), “Position” (wall, desk, or split), and “System Cues” (information richness). In an experimental setting involving 20 participants, we investigated how these factors influence satisfaction and acceptance of automation. Using an adapted Post-Study System Usability Questionnaire (PSSUQ), we evaluated satisfaction with Ease of Use, Reachability, and Information. Findings show that while participants’ initial expectations favored simple analog controls, preferences shifted toward digital, information-rich systems after hands-on interaction. Ordered logistic regression confirmed that Reachability (β=2.317) and Ease of Use (β=1.831) were the strongest predictors of Overall Satisfaction (p<0.001), placing interface position as the primary design characteristic. However, preferences varied by office type: in shared offices, users preferred wall-mounted controls to facilitate shared access and visibility. These insights offer actionable guidance for designing smart control interfaces that enhance user satisfaction, support personal control, and promote greater acceptance of building automation.
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The integration of smart control systems in office buildings can be disruptive when individual preferences and expectations for control interfaces are overlooked. Understanding how human–building interaction influences environmental comfort and acceptance is essential for creating user-centered designs. This study aimed to evaluate the effectiveness of usability testing as an innovative method for assessing building system control interfaces and user interaction with automation. Specifically, we examined user preferences for shading and lighting controls in a controlled office laboratory, varying by “Type of Device” (analog vs. digital), “Position” (wall, desk, or split), and “System Cues” (information richness). In an experimental setting involving 20 participants, we investigated how these factors influence satisfaction and acceptance of automation. Using an adapted Post-Study System Usability Questionnaire (PSSUQ), we evaluated satisfaction with Ease of Use, Reachability, and Information. Findings show that while participants’ initial expectations favored simple analog controls, preferences shifted toward digital, information-rich systems after hands-on interaction. Ordered logistic regression confirmed that Reachability (β=2.317) and Ease of Use (β=1.831) were the strongest predictors of Overall Satisfaction (p<0.001), placing interface position as the primary design characteristic. However, preferences varied by office type: in shared offices, users preferred wall-mounted controls to facilitate shared access and visibility. These insights offer actionable guidance for designing smart control interfaces that enhance user satisfaction, support personal control, and promote greater acceptance of building automation.
Building Automation and Control Systems (BACS) enhance energy efficiency in office buildings but often leave occupants dissatisfied, especially in shared offices with diverse indoor environmental preferences. Personal Comfort Models (PCM) capture individual preferences, yet these models can be difficult to apply in shared environments. This study examines whether a generalized personalized modeling would be necessary, or instead aggregated thermal preferences adequately represent individual needs in shared spaces. By mining the ASHRAE Global Thermal Comfort Database II, we analyzed 11 naturally ventilated office buildings spanning four climate zones, each providing 187 to 568 data points of subjective thermal preferences and concurrent environmental measurements. To capture uncertainties in occupant feedback and monitoring, we developed a Bayesian multinomial logistic framework. We compare an aggregated model (all responses together) with a hierarchical (partial-pooling) model having occupant-specific intercepts, using the No‑U‑Turn Sampler for Hamiltonian Monte Carlo. The Widely Applicable Bayesian Information Criterion confirms that hierarchical approach outperforms the aggregated model in every case. In four of the eleven studies, aggregated air temperature ranges satisfied occupants’ demands within a 95% posterior credible interval. Moreover, in most buildings, these temperature ranges aligned well with the majority of occupant preferences, suggesting that prior knowledge of building conditions or occupant variability might reduce the need for highly customized thermal environment. Future research should explore these findings in conditioned buildings and across other indoor environmental quality domains, where greater variability could exist.
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Building Automation and Control Systems (BACS) enhance energy efficiency in office buildings but often leave occupants dissatisfied, especially in shared offices with diverse indoor environmental preferences. Personal Comfort Models (PCM) capture individual preferences, yet these models can be difficult to apply in shared environments. This study examines whether a generalized personalized modeling would be necessary, or instead aggregated thermal preferences adequately represent individual needs in shared spaces. By mining the ASHRAE Global Thermal Comfort Database II, we analyzed 11 naturally ventilated office buildings spanning four climate zones, each providing 187 to 568 data points of subjective thermal preferences and concurrent environmental measurements. To capture uncertainties in occupant feedback and monitoring, we developed a Bayesian multinomial logistic framework. We compare an aggregated model (all responses together) with a hierarchical (partial-pooling) model having occupant-specific intercepts, using the No‑U‑Turn Sampler for Hamiltonian Monte Carlo. The Widely Applicable Bayesian Information Criterion confirms that hierarchical approach outperforms the aggregated model in every case. In four of the eleven studies, aggregated air temperature ranges satisfied occupants’ demands within a 95% posterior credible interval. Moreover, in most buildings, these temperature ranges aligned well with the majority of occupant preferences, suggesting that prior knowledge of building conditions or occupant variability might reduce the need for highly customized thermal environment. Future research should explore these findings in conditioned buildings and across other indoor environmental quality domains, where greater variability could exist.
Corrigendum to ‘Resilience readiness levels for buildings
Establishing multi-hazard resilience metrics and rating systems’(International Journal of Disaster Risk Reduction, (2025), 128, C, (105746), (S2212420925005709), 10.1016/j.ijdrr.2025.105746)
Journal article
(2026)
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Simona Bianchi, Michele Matteoni, Kyujin Kim, Anna Maria Koniari, Kyra Koning, Alessandra Luna-Navarro, Zhikai Peng, Anna Silva, Mauro Overend, More Authors
The authors wish to replace the flood hazard map in Fig. 11a with an updated map for the Acerra region. The legend has been revised to display only the minimum and maximum flood depth values.(Figure presented) Fig. 11. (a) Flood hazard map for the Acerra region (Pluvial flooding - RCP 8.5 for year 2050, 50th Percentile - 1000 years return period) overlayed on the case study buildings (highlighted in orange).
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The authors wish to replace the flood hazard map in Fig. 11a with an updated map for the Acerra region. The legend has been revised to display only the minimum and maximum flood depth values.(Figure presented) Fig. 11. (a) Flood hazard map for the Acerra region (Pluvial flooding - RCP 8.5 for year 2050, 50th Percentile - 1000 years return period) overlayed on the case study buildings (highlighted in orange).
Conference paper
(2026)
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Eleni Chatzi Nestoros, Pablo Martinez-Alcaraz, Alejandro Fuentes, Juan Diego Blanco Cadena, Michela Turrin, Tiziana Poli, Alessandra Luna-Navarro
Urbanization and climate change have intensified urban heat island effects, significantly affecting outdoor thermal comfort (OTC) in cities. Traditional methods of assessing the influence of urban environments on OTC often rely heavily on computational simulations, neglecting the integration of user-centric data and comprehensive environmental monitoring. This study investigates the relationship between microclimatic conditions, thermal sensation, and human preferences to identify the key factors influencing outdoor thermal comfort. Using the Acquabella district in Milan as a case study, the research adopts a cross-examination approach that integrates qualitative and quantitative assessments to evaluate outdoor thermal conditions. The methodology combines user-centered participatory approaches, including a workshop and an online survey, to identify critical intervention areas and factors contributing to thermal discomfort. Thermal Sensation Votes (TSV) are collected and analyzed in QGIS, highlighting significant environmental and psychological factors influencing user perception. Preliminary simulations using SOLWEIG are employed to cross-examine the results, identifying spaces with varying levels of thermal comfort. This study underscores the value of combining objective and subjective measures to pinpoint areas of critical environmental quality and optimize decision-making processes. By leveraging user data, the methodology reduces computational demands while offering actionable insights for urban health. The approach is scalable to different urban contexts, fostering the development of resilient and climate-adaptive environments.
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Urbanization and climate change have intensified urban heat island effects, significantly affecting outdoor thermal comfort (OTC) in cities. Traditional methods of assessing the influence of urban environments on OTC often rely heavily on computational simulations, neglecting the integration of user-centric data and comprehensive environmental monitoring. This study investigates the relationship between microclimatic conditions, thermal sensation, and human preferences to identify the key factors influencing outdoor thermal comfort. Using the Acquabella district in Milan as a case study, the research adopts a cross-examination approach that integrates qualitative and quantitative assessments to evaluate outdoor thermal conditions. The methodology combines user-centered participatory approaches, including a workshop and an online survey, to identify critical intervention areas and factors contributing to thermal discomfort. Thermal Sensation Votes (TSV) are collected and analyzed in QGIS, highlighting significant environmental and psychological factors influencing user perception. Preliminary simulations using SOLWEIG are employed to cross-examine the results, identifying spaces with varying levels of thermal comfort. This study underscores the value of combining objective and subjective measures to pinpoint areas of critical environmental quality and optimize decision-making processes. By leveraging user data, the methodology reduces computational demands while offering actionable insights for urban health. The approach is scalable to different urban contexts, fostering the development of resilient and climate-adaptive environments.
Conference paper
(2026)
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Pedro de la Barra, Pablo Martinez-Alcaraz, Eleonora Brembilla, Alessandra Luna-Navarro
The integration of smart control systems in office buildings often neglects individual expectations and preferences, especially when occupants do not have personal control over their environment. While existing research has advanced personalized comfort models, simulated energy-use behaviors, and quantitative methods for occupant-centric building design, it often overlooks the critical role of personalized control interfaces. These interfaces are essential for integrating occupants into the operable building systems. This study investigates occupant preferences for personal control after experiencing different building control interfaces for lighting and roller shades in an office environment. Using a usability testing approach, 20 participants were involved in brief interaction sessions to evaluate how interface type (digital vs. analogue), position (wall-mounted vs. desk-mounted), and level of information influence occupants’ satisfaction. Additionally, we explored whether participants’ preferences for indoor environmental quality conditions correspond with their reported satisfaction with building control interfaces. Results show that interface placement significantly influences user preference, beyond ease of access. While participants initially favored analogue controls and manual operation, exposure to digital and automated systems led to greater acceptance, particularly when these systems provided clear information and maintained personal control. These findings underscore the importance of actual experiences with system interfaces in understanding occupant preferences and acceptance with building technologies, which is key for occupant-centered design in building control.
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The integration of smart control systems in office buildings often neglects individual expectations and preferences, especially when occupants do not have personal control over their environment. While existing research has advanced personalized comfort models, simulated energy-use behaviors, and quantitative methods for occupant-centric building design, it often overlooks the critical role of personalized control interfaces. These interfaces are essential for integrating occupants into the operable building systems. This study investigates occupant preferences for personal control after experiencing different building control interfaces for lighting and roller shades in an office environment. Using a usability testing approach, 20 participants were involved in brief interaction sessions to evaluate how interface type (digital vs. analogue), position (wall-mounted vs. desk-mounted), and level of information influence occupants’ satisfaction. Additionally, we explored whether participants’ preferences for indoor environmental quality conditions correspond with their reported satisfaction with building control interfaces. Results show that interface placement significantly influences user preference, beyond ease of access. While participants initially favored analogue controls and manual operation, exposure to digital and automated systems led to greater acceptance, particularly when these systems provided clear information and maintained personal control. These findings underscore the importance of actual experiences with system interfaces in understanding occupant preferences and acceptance with building technologies, which is key for occupant-centered design in building control.
Conference paper
(2026)
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E.R.L. Lenarduzzi, S. Maniatis, Alessandra Luna-Navarro, M.U.J. Peeters, Hadrien Heuclin, Francois Guillemot, R.C. Hartwell
The reuse and high-value recovery of architectural glazing offer significant potential to reduce waste and minimize the environmental impact of the glass sector. Still, there is a lack of a standardised approach to support decisions in environmentally efficient renovation pathways that integrate all life-cycle stages and account for varying glazing types, geographical locations, and service-life dynamics. This study develops a novel assessment framework to quantify the environmental and financial trade-offs of alternative glass recovery pathways. The computational framework incorporates life-cycle embodied carbon analyses across material recovery scenarios and temporal energy simulations parameterized by panel geometry, build-up, window condition, and collection site. The framework was applied to six reference glazing products in residential and commercial case studies located in France. It was found that carbon payback periods range from under five years for deteriorated early-generation glazing to well beyond 25 years for non-deteriorated products or products subject to high-infiltration conditions, highlighting the importance of existing building condition in guiding intervention decisions. Under current market conditions, it is shown that despite their embodied carbon benefits, reuse and remanufacturing both incur substantially higher 30-year net present value costs (EUR) compared to recycling recovered glazing and installing new high performance IGUs.
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The reuse and high-value recovery of architectural glazing offer significant potential to reduce waste and minimize the environmental impact of the glass sector. Still, there is a lack of a standardised approach to support decisions in environmentally efficient renovation pathways that integrate all life-cycle stages and account for varying glazing types, geographical locations, and service-life dynamics. This study develops a novel assessment framework to quantify the environmental and financial trade-offs of alternative glass recovery pathways. The computational framework incorporates life-cycle embodied carbon analyses across material recovery scenarios and temporal energy simulations parameterized by panel geometry, build-up, window condition, and collection site. The framework was applied to six reference glazing products in residential and commercial case studies located in France. It was found that carbon payback periods range from under five years for deteriorated early-generation glazing to well beyond 25 years for non-deteriorated products or products subject to high-infiltration conditions, highlighting the importance of existing building condition in guiding intervention decisions. Under current market conditions, it is shown that despite their embodied carbon benefits, reuse and remanufacturing both incur substantially higher 30-year net present value costs (EUR) compared to recycling recovered glazing and installing new high performance IGUs.
Building automation and control systems (BACS) are central to energy performance and occupant comfort in non-residential buildings. Comfort is inherently multi-domain, including thermal, visual, acoustic, and air quality requirements. Multi-domain BACS involves frequent trade-offs across domains when conflicting control actions arise, such as providing glare control versus daylight availability. Yet existing occupant-centric control research treats building services in isolation, and prior multi-domain comfort reviews rarely examine how multi-domain demands are integrated into BACS decision logic across services. We conducted a systematic review of 43 studies to examine how multi-domain occupant demands are represented and operationalized in BACS. Across the evidence base, thermal comfort is universal, while visual and air quality are frequently included. Acoustics is rarely addressed due controllability constraints. Most studies remain unimodal in their demand representation, even when multiple domains are in scope. Integrated BACS implementations are therefore largely built on within-domain formulations. Multimodal demand models that encode cross-domain and combined effects are uncommon and are rarely implemented in integrated BACS. Rule-based strategies dominate multi-domain controllers. Optimization-based and learning-based controllers are also used, but they often rely on fixed weights or reward terms that make trade-offs difficult to interpret. In addition, actuator choice is rarely made explicit when multiple services can achieve the same target state. Future research should benchmark unimodal and multimodal demand formulations under comparable control contexts, extend bottom-up multimodal models beyond thermal and air quality into integrated BACS, especially for façade control, and develop transparent, preference-aware policy designs that make priorities and service actions understandable.
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Building automation and control systems (BACS) are central to energy performance and occupant comfort in non-residential buildings. Comfort is inherently multi-domain, including thermal, visual, acoustic, and air quality requirements. Multi-domain BACS involves frequent trade-offs across domains when conflicting control actions arise, such as providing glare control versus daylight availability. Yet existing occupant-centric control research treats building services in isolation, and prior multi-domain comfort reviews rarely examine how multi-domain demands are integrated into BACS decision logic across services. We conducted a systematic review of 43 studies to examine how multi-domain occupant demands are represented and operationalized in BACS. Across the evidence base, thermal comfort is universal, while visual and air quality are frequently included. Acoustics is rarely addressed due controllability constraints. Most studies remain unimodal in their demand representation, even when multiple domains are in scope. Integrated BACS implementations are therefore largely built on within-domain formulations. Multimodal demand models that encode cross-domain and combined effects are uncommon and are rarely implemented in integrated BACS. Rule-based strategies dominate multi-domain controllers. Optimization-based and learning-based controllers are also used, but they often rely on fixed weights or reward terms that make trade-offs difficult to interpret. In addition, actuator choice is rarely made explicit when multiple services can achieve the same target state. Future research should benchmark unimodal and multimodal demand formulations under comparable control contexts, extend bottom-up multimodal models beyond thermal and air quality into integrated BACS, especially for façade control, and develop transparent, preference-aware policy designs that make priorities and service actions understandable.
Conference paper
(2026)
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P. de la Barra, M. S. Khanie, A. Luna-Navarro, P. Martinez-Alcaraz, D. Al Assaad, E. M. Barrett, G. Chinazzo, Z. Deng, B. Dong, More Authors
Buildings are striving to be both energy-efficient and occupant-centered. Personalized systems for lighting and dynamic fenestration systems, e.g., switchable glazing, are emerging as a key solution. These systems, called Personalized Environmental Control Systems (PECS), allow individuals to adjust their immediate environment without impacting others. While PECS initially focused on temperature and air quality, this study explores the potential for the luminous environment, introducing the concept of Visual PECS.
Daylighting and lighting controls build on a long history of personalized systems and methods, from prehistoric torches to adjustable desk lamps. They allow for individual control over (day)light spectrum and intensity, catering to personal needs and promoting circadian health and cellular processes (i.e., photobiomodulation). Additionally, they can reduce glare and improve visual comfort, leading to increased productivity and well-being. Despite this long history, studies formulating “personalized environmental control systems” (PECS) in the daylighting and lighting domain are rare. In this paper, we present preliminary results from a comprehensive review, where 31 papers were identified from an initial pool of 5,238. The findings highlighted two key benefits. First, semi-automated PECS offer the highest energy savings, highlighting the importance of understanding the relationship between users and automation. Secondly, PECS provides improved occupant experience since the ability to control their environment empowers occupants, leading to increased comfort and productivity. Overall, PECS have the potential to facilitate individual control over lighting and visual parameters, ultimately enhancing visual comfort and satisfaction as well as beyond-visual well-being. Our research builds upon the ongoing work of IEA EBC - Annex 87, which investigates the energy and environmental benefits of PECS. ...
Daylighting and lighting controls build on a long history of personalized systems and methods, from prehistoric torches to adjustable desk lamps. They allow for individual control over (day)light spectrum and intensity, catering to personal needs and promoting circadian health and cellular processes (i.e., photobiomodulation). Additionally, they can reduce glare and improve visual comfort, leading to increased productivity and well-being. Despite this long history, studies formulating “personalized environmental control systems” (PECS) in the daylighting and lighting domain are rare. In this paper, we present preliminary results from a comprehensive review, where 31 papers were identified from an initial pool of 5,238. The findings highlighted two key benefits. First, semi-automated PECS offer the highest energy savings, highlighting the importance of understanding the relationship between users and automation. Secondly, PECS provides improved occupant experience since the ability to control their environment empowers occupants, leading to increased comfort and productivity. Overall, PECS have the potential to facilitate individual control over lighting and visual parameters, ultimately enhancing visual comfort and satisfaction as well as beyond-visual well-being. Our research builds upon the ongoing work of IEA EBC - Annex 87, which investigates the energy and environmental benefits of PECS. ...
Buildings are striving to be both energy-efficient and occupant-centered. Personalized systems for lighting and dynamic fenestration systems, e.g., switchable glazing, are emerging as a key solution. These systems, called Personalized Environmental Control Systems (PECS), allow individuals to adjust their immediate environment without impacting others. While PECS initially focused on temperature and air quality, this study explores the potential for the luminous environment, introducing the concept of Visual PECS.
Daylighting and lighting controls build on a long history of personalized systems and methods, from prehistoric torches to adjustable desk lamps. They allow for individual control over (day)light spectrum and intensity, catering to personal needs and promoting circadian health and cellular processes (i.e., photobiomodulation). Additionally, they can reduce glare and improve visual comfort, leading to increased productivity and well-being. Despite this long history, studies formulating “personalized environmental control systems” (PECS) in the daylighting and lighting domain are rare. In this paper, we present preliminary results from a comprehensive review, where 31 papers were identified from an initial pool of 5,238. The findings highlighted two key benefits. First, semi-automated PECS offer the highest energy savings, highlighting the importance of understanding the relationship between users and automation. Secondly, PECS provides improved occupant experience since the ability to control their environment empowers occupants, leading to increased comfort and productivity. Overall, PECS have the potential to facilitate individual control over lighting and visual parameters, ultimately enhancing visual comfort and satisfaction as well as beyond-visual well-being. Our research builds upon the ongoing work of IEA EBC - Annex 87, which investigates the energy and environmental benefits of PECS.
Daylighting and lighting controls build on a long history of personalized systems and methods, from prehistoric torches to adjustable desk lamps. They allow for individual control over (day)light spectrum and intensity, catering to personal needs and promoting circadian health and cellular processes (i.e., photobiomodulation). Additionally, they can reduce glare and improve visual comfort, leading to increased productivity and well-being. Despite this long history, studies formulating “personalized environmental control systems” (PECS) in the daylighting and lighting domain are rare. In this paper, we present preliminary results from a comprehensive review, where 31 papers were identified from an initial pool of 5,238. The findings highlighted two key benefits. First, semi-automated PECS offer the highest energy savings, highlighting the importance of understanding the relationship between users and automation. Secondly, PECS provides improved occupant experience since the ability to control their environment empowers occupants, leading to increased comfort and productivity. Overall, PECS have the potential to facilitate individual control over lighting and visual parameters, ultimately enhancing visual comfort and satisfaction as well as beyond-visual well-being. Our research builds upon the ongoing work of IEA EBC - Annex 87, which investigates the energy and environmental benefits of PECS.
The provision of personalized air velocity for occupants in open-plan offices during summer has the potential to enhance comfort, productivity and energy efficiency, by integrating Personalised Environmental Control Systems (PECS) in open plan offices. However, the design and integration of PECS in open space offices is often hindered by several design challenges, while the user-centred design of PECS requires the simultaneous understanding of several human requirements from a multi-domain perspective, ranging from ergonomics disciplines to indoor climate sciences. First, this study conducted interviews with practitioners from the indoor climate and office design sectors to evaluate the requirements of several stakeholders involved in the design of office spaces. Secondly, interviews with end-users are conducted to evaluate the key factors influencing user satisfaction with PECS. On the basis of these results, a framework is proposed to support the design of occupant-centred systems for increasing air movement in office spaces in a personalized and local manner. The framework identifies essential design factors and criteria, distinguishing between must-have and optional elements in user-centred PECS. Overall, this research contributes to the advancement of personalized environmental control systems, offering insights applicable to various workplace settings and climatic conditions.
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The provision of personalized air velocity for occupants in open-plan offices during summer has the potential to enhance comfort, productivity and energy efficiency, by integrating Personalised Environmental Control Systems (PECS) in open plan offices. However, the design and integration of PECS in open space offices is often hindered by several design challenges, while the user-centred design of PECS requires the simultaneous understanding of several human requirements from a multi-domain perspective, ranging from ergonomics disciplines to indoor climate sciences. First, this study conducted interviews with practitioners from the indoor climate and office design sectors to evaluate the requirements of several stakeholders involved in the design of office spaces. Secondly, interviews with end-users are conducted to evaluate the key factors influencing user satisfaction with PECS. On the basis of these results, a framework is proposed to support the design of occupant-centred systems for increasing air movement in office spaces in a personalized and local manner. The framework identifies essential design factors and criteria, distinguishing between must-have and optional elements in user-centred PECS. Overall, this research contributes to the advancement of personalized environmental control systems, offering insights applicable to various workplace settings and climatic conditions.
Journal article
(2026)
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Alvaro Balderrama, Alessandra Luna-Navarro, Jian Kang, Hussam Al Basha, Eric Verschuur, Daniel Arztmann, Ulrich Knaack
As automation is progressively more present in buildings, it is important to understand its impact on people’s experience of urban environments. This case study investigated how one automated shading system with motorized venetian blinds affects sound perception of the acoustic environment in the immediate outdoor surroundings of a university campus building in Detmold, Germany. Procedures of ISO 12913 series for soundscape research were followed to conduct acoustic measurements and derive psychoacoustic indicators. Additionally, soundwalks involving 41 participants and a laboratory study using immersive virtual reality (VR) with 34 participants were conducted to assess how individuals perceive the acoustic environment. The results show that the operation of automated blinds increases sound levels above reference thresholds at short distances, and has a consistent effect on the soundscape, shifting it from pleasant and calm to annoying and chaotic. These trends are notable in both on-site and laboratory data. Additionally, when participants evaluated the soundscape in direct visual connection with the operating façade shading system, they perceived the sounds to be less chaotic than when they were not seeing the façade. These findings highlight that automated buildings and façades are active sound sources capable of influencing environmental quality through acoustic and non-acoustic effects; therefore, their influence on the soundscape should be considered within performance assessments, smart/automation policy, and sustainability frameworks.
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As automation is progressively more present in buildings, it is important to understand its impact on people’s experience of urban environments. This case study investigated how one automated shading system with motorized venetian blinds affects sound perception of the acoustic environment in the immediate outdoor surroundings of a university campus building in Detmold, Germany. Procedures of ISO 12913 series for soundscape research were followed to conduct acoustic measurements and derive psychoacoustic indicators. Additionally, soundwalks involving 41 participants and a laboratory study using immersive virtual reality (VR) with 34 participants were conducted to assess how individuals perceive the acoustic environment. The results show that the operation of automated blinds increases sound levels above reference thresholds at short distances, and has a consistent effect on the soundscape, shifting it from pleasant and calm to annoying and chaotic. These trends are notable in both on-site and laboratory data. Additionally, when participants evaluated the soundscape in direct visual connection with the operating façade shading system, they perceived the sounds to be less chaotic than when they were not seeing the façade. These findings highlight that automated buildings and façades are active sound sources capable of influencing environmental quality through acoustic and non-acoustic effects; therefore, their influence on the soundscape should be considered within performance assessments, smart/automation policy, and sustainability frameworks.
Additive manufacturing with varying material properties of thermosetting reactive polymers
A framework and comparison of different modes for implementing material transitions
Additive Manufacturing with Varying Material Properties enables controlled spatial variation of material properties in 3D-printed components, facilitating custom-tailored characteristics, added functionalities and reduced assembly processes. To promote this approach in building façade applications, this paper presents a novel framework for Additive Manufacturing with varying material properties using a thermosetting reactive polymer, specifically polyurethane. By dynamically changing the polyurethane’s chemical composition, the material properties can be precisely controlled. The framework’s individual aspects, including the material, hardware setup and computational system, are described in detail. Additionally, the research explores the implementation of material transitions with this framework, highlighting three different modes (horizontal, vertical and multi plane) and their impact on print time and material consumption. The paper concludes by discussing the potential of this approach for building façade applications, addressing current challenges and outlining future research directions.
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Additive Manufacturing with Varying Material Properties enables controlled spatial variation of material properties in 3D-printed components, facilitating custom-tailored characteristics, added functionalities and reduced assembly processes. To promote this approach in building façade applications, this paper presents a novel framework for Additive Manufacturing with varying material properties using a thermosetting reactive polymer, specifically polyurethane. By dynamically changing the polyurethane’s chemical composition, the material properties can be precisely controlled. The framework’s individual aspects, including the material, hardware setup and computational system, are described in detail. Additionally, the research explores the implementation of material transitions with this framework, highlighting three different modes (horizontal, vertical and multi plane) and their impact on print time and material consumption. The paper concludes by discussing the potential of this approach for building façade applications, addressing current challenges and outlining future research directions.
Behaviour Nudging for User Acceptance in Smart Blinds Control
A Pilot Study on Behaviour Change and Indoor Environmental Enhancement
Conference paper
(2025)
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Wen Ting Li, Alessandra Luna-Navarro, Pedro de la Barra Luegmayer, Michele Win Tai Mak, Han Fang
Automated blinds represent a smart façade strategy that responds to real-time environmental conditions and user needs, dynamically modulating daylight and radiant heat gain to support energy performance and enhance indoor thermal and visual comfort in buildings. However, user disengagement and frequent manual overrides challenge their effectiveness. This override behaviour often stems from a lack of perceived control and insufficient awareness of environmental benefits. Behavioural nudging, particularly through gamification, offers a promising approach to encourage user interaction with automated systems without compromising autonomy. Despite its success in fields such as health and education, limited research has explored its application in the control systems for the built environment. This study explores how gamification can function as a behavioural nudge in smart environmental controls by implementing an exploratory questionnaire focused on user engagement, preferences, and decision-making in the context of automated blinds. A structured questionnaire was proposed to explore the impact of gamification elements, such as feedback, incentives, and social comparison-while accounting for user-specific factors like personality and familiarity with smart technologies. Preliminary results indicate that personalised feedback and peer-based comparisons enhance engagement and system acceptability. These findings offer early guidance for designing human-centric adaptive systems that balance automation with user participation, supporting energy efficiency and well-being in indoor environments.
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Automated blinds represent a smart façade strategy that responds to real-time environmental conditions and user needs, dynamically modulating daylight and radiant heat gain to support energy performance and enhance indoor thermal and visual comfort in buildings. However, user disengagement and frequent manual overrides challenge their effectiveness. This override behaviour often stems from a lack of perceived control and insufficient awareness of environmental benefits. Behavioural nudging, particularly through gamification, offers a promising approach to encourage user interaction with automated systems without compromising autonomy. Despite its success in fields such as health and education, limited research has explored its application in the control systems for the built environment. This study explores how gamification can function as a behavioural nudge in smart environmental controls by implementing an exploratory questionnaire focused on user engagement, preferences, and decision-making in the context of automated blinds. A structured questionnaire was proposed to explore the impact of gamification elements, such as feedback, incentives, and social comparison-while accounting for user-specific factors like personality and familiarity with smart technologies. Preliminary results indicate that personalised feedback and peer-based comparisons enhance engagement and system acceptability. These findings offer early guidance for designing human-centric adaptive systems that balance automation with user participation, supporting energy efficiency and well-being in indoor environments.
Conference paper
(2025)
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P. Martinez-Alcaraz, P. de la Barra, C. P. Andriotis, Y. Wang, A. Luna-Navarro
It is a challenge for traditional building control systems to meet occupants’ needs in shared spaces due to the lack of understanding of individual occupant thermal preferences. This is a barrier to balancing energy efficiency and indoor environmental quality (IEQ). Advanced statistical learning methods offer new solutions towards more energy-efficient and user-centric control logics. In this work, a control logic is proposed to optimise the heating, ventilation and air conditioning (HVAC) operation based on thermal comfort archetype preferences, leveraging the ASHRAE Global Thermal Comfort Database II in conjunction with energy simulations. First, we apply the k-means clustering algorithm to categorize occupants into different archetypes regarding their common feedback on the thermal environment. Then, we fit a Bayesian logistic regression model to predict the thermal comfort preferences of different archetypes based on IEQ data. Finally, we identify two occupant-centric control logics to optimize HVAC operation to meet occupants’ requirements: (i) considering a unified response of thermal comfort in the space, and (ii) ensuring the dynamic optimal setpoint when conflicting occupant archetypes are present. Having compared this control logic with a common rule-based logic, our results demonstrate the potential of occupant-centric controls and the importance of multi-objective metrics in accounting for energy efficiency.
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It is a challenge for traditional building control systems to meet occupants’ needs in shared spaces due to the lack of understanding of individual occupant thermal preferences. This is a barrier to balancing energy efficiency and indoor environmental quality (IEQ). Advanced statistical learning methods offer new solutions towards more energy-efficient and user-centric control logics. In this work, a control logic is proposed to optimise the heating, ventilation and air conditioning (HVAC) operation based on thermal comfort archetype preferences, leveraging the ASHRAE Global Thermal Comfort Database II in conjunction with energy simulations. First, we apply the k-means clustering algorithm to categorize occupants into different archetypes regarding their common feedback on the thermal environment. Then, we fit a Bayesian logistic regression model to predict the thermal comfort preferences of different archetypes based on IEQ data. Finally, we identify two occupant-centric control logics to optimize HVAC operation to meet occupants’ requirements: (i) considering a unified response of thermal comfort in the space, and (ii) ensuring the dynamic optimal setpoint when conflicting occupant archetypes are present. Having compared this control logic with a common rule-based logic, our results demonstrate the potential of occupant-centric controls and the importance of multi-objective metrics in accounting for energy efficiency.
Journal article
(2025)
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Dolaana Khovalyg, Mariya P. Bivolarova, Jun Shinoda, Douaa Al-Assaad, Marika Vellei, Karol Bandurski, Pablo Martinez Alcaraz, P. de la Barra Luegmayer, Alessandra Luna-Navarro, More authors...
Advances in environmental technologies have improved indoor environmental quality (IEQ) by creating steady, uniform conditions. However, these often fail to meet individual thermal comfort and air quality needs, prompting a shift toward adaptive, personalized solutions. Personalized Environmental Control Systems (PECS) aim to enhance comfort, air quality, health, and productivity through user-centered designs. This paper systematically reviews 324 journal articles on PECS from 1988-2023, focusing on thermal and indoor air quality (IAQ) domains. PECS are classified by mobility: building-attached, semi-attached, detached, and wearable. The review assesses their impact on thermal comfort, IAQ, health outcomes (e.g., Sick Building Syndrome, heat stress), and human performance (e.g., cognitive function, productivity). Results show that building-detached PECS often improve thermal sensation, comfort, and acceptability, with combined systems yielding better ratings. Personalized ventilation enhances IAQ by delivering clean air directly to the breathing zone, reducing contaminant exposure. Research on PECS effects on health is limited, mainly focusing on short-term, controlled studies. Evidence for benefits on human performance is sparse but promising. Key challenges include inconsistent performance metrics, limited real-world evaluations, and potential publication bias toward positive results. This review highlights the need for standardized evaluation methods, deeper understanding of combined PECS effects, real-world and long-term testing, and clearer quantification of human performance benefits to advance the field.
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Advances in environmental technologies have improved indoor environmental quality (IEQ) by creating steady, uniform conditions. However, these often fail to meet individual thermal comfort and air quality needs, prompting a shift toward adaptive, personalized solutions. Personalized Environmental Control Systems (PECS) aim to enhance comfort, air quality, health, and productivity through user-centered designs. This paper systematically reviews 324 journal articles on PECS from 1988-2023, focusing on thermal and indoor air quality (IAQ) domains. PECS are classified by mobility: building-attached, semi-attached, detached, and wearable. The review assesses their impact on thermal comfort, IAQ, health outcomes (e.g., Sick Building Syndrome, heat stress), and human performance (e.g., cognitive function, productivity). Results show that building-detached PECS often improve thermal sensation, comfort, and acceptability, with combined systems yielding better ratings. Personalized ventilation enhances IAQ by delivering clean air directly to the breathing zone, reducing contaminant exposure. Research on PECS effects on health is limited, mainly focusing on short-term, controlled studies. Evidence for benefits on human performance is sparse but promising. Key challenges include inconsistent performance metrics, limited real-world evaluations, and potential publication bias toward positive results. This review highlights the need for standardized evaluation methods, deeper understanding of combined PECS effects, real-world and long-term testing, and clearer quantification of human performance benefits to advance the field.
The increase in carbon emissions has contributed to rising global temperatures, necessitating higher energy consumption in buildings to maintain thermal comfort during the summer months. The building envelope, as the protective layer of a building, plays a critical role in maintaining indoor comfort and dictating building energy use. However, when assessing the performance of the building envelope, occupant interaction is poorly considered. This study investigates the impact of occupant façade interaction when evaluating alternative façade solutions for thermal comfort in summer season. Occupant behaviour models, specifically window operation models, are identified and implemented to assess their impact on indoor comfort and air quality. This is done by first identifying façade archetypes and generating scenarios with selected occupant behavior models. The results revealed that occupant interaction with windows significantly impact internal air temperatures and thermal comfort, while alternative façade solutions have a relatively lower impact. Largest ventilation areas were associated with lower air temperatures. Consequently, the number of discomfort hours are also lower in scenarios with occupant interaction compared to without. The impact of the façade ventilation area, window-to-wall ratio and thermal mass was more relevant in the scenarios where windows were always closed. The findings of this study can serve as a foundation for the development of strategies that promote occupant interaction with the façade which can lead to reduced building energy demand.
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The increase in carbon emissions has contributed to rising global temperatures, necessitating higher energy consumption in buildings to maintain thermal comfort during the summer months. The building envelope, as the protective layer of a building, plays a critical role in maintaining indoor comfort and dictating building energy use. However, when assessing the performance of the building envelope, occupant interaction is poorly considered. This study investigates the impact of occupant façade interaction when evaluating alternative façade solutions for thermal comfort in summer season. Occupant behaviour models, specifically window operation models, are identified and implemented to assess their impact on indoor comfort and air quality. This is done by first identifying façade archetypes and generating scenarios with selected occupant behavior models. The results revealed that occupant interaction with windows significantly impact internal air temperatures and thermal comfort, while alternative façade solutions have a relatively lower impact. Largest ventilation areas were associated with lower air temperatures. Consequently, the number of discomfort hours are also lower in scenarios with occupant interaction compared to without. The impact of the façade ventilation area, window-to-wall ratio and thermal mass was more relevant in the scenarios where windows were always closed. The findings of this study can serve as a foundation for the development of strategies that promote occupant interaction with the façade which can lead to reduced building energy demand.
Review
(2025)
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María Victoria Dávalos Quevedo, Alessandra Luna-Navarro, Uta Pottgiesser, Ulrich Blum
Occupant satisfaction in office spaces is a critical factor influencing occupant’s productivity, satisfaction and overall workplace experience. This systematic review examines the methodologies and approaches used to assess occupant satisfaction with office space design, identifying key evaluation tools and research trends. The study explores the extent to which existing methodologies integrate environmental, spatial and design factors to provide a comprehensive understanding of user experience. Additionally, it highlights the limitations in current assessment tools, including the lack of standardised frameworks for capturing occupant feedback at different stages of the design process. The findings suggest a growing shift towards data-driven and real-time feedback mechanisms to enhance workplace adaptability. By synthesising existing research, this review aims to provide insights for designers, facility managers and policymakers to refine evaluation methods and integrate occupant-centric strategies into office space planning.
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Occupant satisfaction in office spaces is a critical factor influencing occupant’s productivity, satisfaction and overall workplace experience. This systematic review examines the methodologies and approaches used to assess occupant satisfaction with office space design, identifying key evaluation tools and research trends. The study explores the extent to which existing methodologies integrate environmental, spatial and design factors to provide a comprehensive understanding of user experience. Additionally, it highlights the limitations in current assessment tools, including the lack of standardised frameworks for capturing occupant feedback at different stages of the design process. The findings suggest a growing shift towards data-driven and real-time feedback mechanisms to enhance workplace adaptability. By synthesising existing research, this review aims to provide insights for designers, facility managers and policymakers to refine evaluation methods and integrate occupant-centric strategies into office space planning.
Thermal Resilience to Extreme Heat
Preliminary Study on Thermal Fragility Curves
Conference paper
(2025)
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Kyujin Kim, Simona Bianchi, Thaleia Konstantinou, Mauro Overend, Jonathan Ciurlanti, Alessandra Luna-Navarro
The increasing frequency and intensity of heatwaves raises questions about the thermal vulnerability of buildings and, in particular, on how to assess their resilience to extreme heat. In this context, thermal fragility curves, which describe the probability of achieving or exceeding specific temperature thresholds for a building, serve as an effective measure to define the thermal vulnerability of existing buildings and identify tailored retrofit strategies. This study focuses on deriving thermal fragility curves for a case study: a 6-storey residential building constructed in the 1980s with a reinforced concrete structure and masonry infill walls. Dynamic thermal modeling and simulation were conducted over a one-year period using synthetic weather files generated to account for future heatwaves. The simulation results provide useful relationships in particular between: outdoor temperature and indoor Standard Effective Temperature (SET); and between outdoor daily maximum temperature and indoor SET. These relationships were finally analyzed to create and compare fragility curves using maximum likelihood fitting and the so-called Cloud methodology.
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The increasing frequency and intensity of heatwaves raises questions about the thermal vulnerability of buildings and, in particular, on how to assess their resilience to extreme heat. In this context, thermal fragility curves, which describe the probability of achieving or exceeding specific temperature thresholds for a building, serve as an effective measure to define the thermal vulnerability of existing buildings and identify tailored retrofit strategies. This study focuses on deriving thermal fragility curves for a case study: a 6-storey residential building constructed in the 1980s with a reinforced concrete structure and masonry infill walls. Dynamic thermal modeling and simulation were conducted over a one-year period using synthetic weather files generated to account for future heatwaves. The simulation results provide useful relationships in particular between: outdoor temperature and indoor Standard Effective Temperature (SET); and between outdoor daily maximum temperature and indoor SET. These relationships were finally analyzed to create and compare fragility curves using maximum likelihood fitting and the so-called Cloud methodology.
Review
(2025)
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P. de la Barra Luegmayer, E. Brembilla, Alejandro Prieto, Claudio Vásquez, U. Knaack, Alessandra Luna-Navarro
In recent years, several studies have assessed the influence of automated façades on energy savings, IEQ, and occupant satisfaction. However, discrepancies exist between the expected advantages of automated façades predicted in research and the actual benefits observed in real-world tests. To assess how automated façade operation enhances building performance, in particular within office building contexts, this study reviews and analyzes current evidence on the influence of automated façades. In this review, 91 studies were identified presenting evidence of their performance. A total of 34 studies investigated performance in laboratory settings, 23 in real office buildings, and 34 in simulations. Only 13 laboratory studies and 17 real office building studies included human participants. Visual and thermal quality were the main indoor environmental domains investigated, with limited exploration of others. Existing studies show large variability in contextual factors (e.g., type of shading and control) or experimental designs (e.g., different benchmark scenarios), hindering the comparison of results. Consistent evidence shows the potential of automated façades for energy savings, particularly in lighting and cooling demands, which outperform manual control systems. Automated controls are more effective in reducing excessive daylight and glare, while evidence of the impact on thermal and air quality remains limited. Regarding occupant satisfaction, evidence is unclear since, in some cases, occupants prefer manually controlled façades and, in others, automated ones. Further research is suggested on human-centered studies in real office buildings to capture occupant behavior and preferences while exploring solutions that dynamically identify and integrate factors affecting occupant interaction with buildings.
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In recent years, several studies have assessed the influence of automated façades on energy savings, IEQ, and occupant satisfaction. However, discrepancies exist between the expected advantages of automated façades predicted in research and the actual benefits observed in real-world tests. To assess how automated façade operation enhances building performance, in particular within office building contexts, this study reviews and analyzes current evidence on the influence of automated façades. In this review, 91 studies were identified presenting evidence of their performance. A total of 34 studies investigated performance in laboratory settings, 23 in real office buildings, and 34 in simulations. Only 13 laboratory studies and 17 real office building studies included human participants. Visual and thermal quality were the main indoor environmental domains investigated, with limited exploration of others. Existing studies show large variability in contextual factors (e.g., type of shading and control) or experimental designs (e.g., different benchmark scenarios), hindering the comparison of results. Consistent evidence shows the potential of automated façades for energy savings, particularly in lighting and cooling demands, which outperform manual control systems. Automated controls are more effective in reducing excessive daylight and glare, while evidence of the impact on thermal and air quality remains limited. Regarding occupant satisfaction, evidence is unclear since, in some cases, occupants prefer manually controlled façades and, in others, automated ones. Further research is suggested on human-centered studies in real office buildings to capture occupant behavior and preferences while exploring solutions that dynamically identify and integrate factors affecting occupant interaction with buildings.
Integrating heat and seismic risk
A multi-objective decision-making approach for facade retrofit design
Conference paper
(2025)
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Kyujin Kim, Simone D’Amore, Alessandra Luna-Navarro, Thaleia Konstantinou, Mauro Overend, Stefano Pampanin, Simona Bianchi
Current multi-hazard risk approaches in seismic engineering primarily focus on structural performance under hazards such as earthquakes, floods, and wind. Despite the distinct risk due to their direct impact on human health, heatwaves receive limited consideration. This unbalanced and fragmented approach is particularly noticeable in facade retrofit design, which has a significant influence on both structural vulnerability during earthquakes and indoor thermal conditions during heatwaves. In this case, integrating seismic and heat risk considerations would help balance performance trade-offs across both domains and assist designers in the selection and combination of technologies that are effective under seismic and heatwave conditions. This study therefore proposes a simulation-based multi-objective methodology for facade retrofit decision making. The suggested approach is demonstrated through a case study: a reinforced concrete building retrofitted using a timber rocking-dissipative external exoskeleton and precast concrete sandwich facade panels. Key facade design parameters-component capacity and dimensioning-were varied to generate a multivariate response for both seismic and thermal performance. The simulation results revealed two challenges for optimization: a limited sample size and nonlinear relationships between design inputs and performance outcomes. To address both, a multivariate regression was applied within segmented performance ranges, defined by breakpoints where the relationship between parameters and performance shifted. The resulting segmented multivariate model enabled the identification of optimal technology combinations within specific performance ranges and the generation of multiple Pareto fronts. This broadened the viable solution space and better supported project-specific trade-off decisions.
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Current multi-hazard risk approaches in seismic engineering primarily focus on structural performance under hazards such as earthquakes, floods, and wind. Despite the distinct risk due to their direct impact on human health, heatwaves receive limited consideration. This unbalanced and fragmented approach is particularly noticeable in facade retrofit design, which has a significant influence on both structural vulnerability during earthquakes and indoor thermal conditions during heatwaves. In this case, integrating seismic and heat risk considerations would help balance performance trade-offs across both domains and assist designers in the selection and combination of technologies that are effective under seismic and heatwave conditions. This study therefore proposes a simulation-based multi-objective methodology for facade retrofit decision making. The suggested approach is demonstrated through a case study: a reinforced concrete building retrofitted using a timber rocking-dissipative external exoskeleton and precast concrete sandwich facade panels. Key facade design parameters-component capacity and dimensioning-were varied to generate a multivariate response for both seismic and thermal performance. The simulation results revealed two challenges for optimization: a limited sample size and nonlinear relationships between design inputs and performance outcomes. To address both, a multivariate regression was applied within segmented performance ranges, defined by breakpoints where the relationship between parameters and performance shifted. The resulting segmented multivariate model enabled the identification of optimal technology combinations within specific performance ranges and the generation of multiple Pareto fronts. This broadened the viable solution space and better supported project-specific trade-off decisions.
Conference paper
(2025)
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M.J. Tenpierik, Z. Huijbregts, T. Konstantinou, E. Brembilla, Alessandra Luna-Navarro, T.T. Jonathan, Spyros Bousios
Rising temperatures are leading to an increase in the cooling demand of buildings. Electrochromic (EC) glazing can be a promising solution for controlling solar heat gains while maintaining outdoor views. This paper presents the results of the monitoring of prototype panels of a novel type of inkjet-printed EC glass under real use and weather conditions in a small office building in the Netherlands. This building contained two identical west-facing meeting rooms of which one was equipped with EC triple glass IGUs and the other with normal triple glass IGUs. Each room was equipped with local heating/cooling units of which the energy use was monitored, and with an extensive environmental sensor network. Sensor and calendar data was fed into an energy balance model for each of the rooms for the entire measurement period, allowing to correct for differences between the two rooms with respect to heat losses and gains and use conditions. The results of the monitoring showed that in the meeting room with EC glass IGUs, the heating demand increased by 34% in Jan.-Mar. 2024 while in Sept. 2023 the cooling demand decreased by 3%. The main reason for the increase in heating demand was found to be the lower g-value of the EC glass IGUs in clear state as compared to the normal IGUs. The almost similar cooling demand was a result of a trade-off between the lower direct solar transmittance of the EC glass IGUs and the heating up of the absorptive layer inside the IGUs. Furthermore, an experiment with participants showed that in general in dark state, satisfaction with view clarity, daylight colour and daylight availability was higher for the EC glass IGUs. In transparent state, no significant difference was perceived between the EC glass IGUs and standard IGUs, except for view clarity.
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Rising temperatures are leading to an increase in the cooling demand of buildings. Electrochromic (EC) glazing can be a promising solution for controlling solar heat gains while maintaining outdoor views. This paper presents the results of the monitoring of prototype panels of a novel type of inkjet-printed EC glass under real use and weather conditions in a small office building in the Netherlands. This building contained two identical west-facing meeting rooms of which one was equipped with EC triple glass IGUs and the other with normal triple glass IGUs. Each room was equipped with local heating/cooling units of which the energy use was monitored, and with an extensive environmental sensor network. Sensor and calendar data was fed into an energy balance model for each of the rooms for the entire measurement period, allowing to correct for differences between the two rooms with respect to heat losses and gains and use conditions. The results of the monitoring showed that in the meeting room with EC glass IGUs, the heating demand increased by 34% in Jan.-Mar. 2024 while in Sept. 2023 the cooling demand decreased by 3%. The main reason for the increase in heating demand was found to be the lower g-value of the EC glass IGUs in clear state as compared to the normal IGUs. The almost similar cooling demand was a result of a trade-off between the lower direct solar transmittance of the EC glass IGUs and the heating up of the absorptive layer inside the IGUs. Furthermore, an experiment with participants showed that in general in dark state, satisfaction with view clarity, daylight colour and daylight availability was higher for the EC glass IGUs. In transparent state, no significant difference was perceived between the EC glass IGUs and standard IGUs, except for view clarity.