Marilyne Andersen

• Swiss Federal Institute of Technology in Lausanne

Any building designed for human occupancy needs to be visually comfortable. Glare from daylight is one of the main causes of visual discomfort. Glare perception is evaluated by empirical glare models either by photometric measurements or by lighting simulations. This study explores an alternate solution that implements deep learning methods to deve...

Amongst the elements often overlooked in existing studies, dynamic movement and temporal changes in the content of views-out have been suggested to have a high potential to improve its perceived quality and occupant satisfaction. Moreover, in past and ongoing view-out research, most view quality indicators and representation methodologies primarily...

Understanding the factors that influence the human perception of glare is necessary to properly address glare risks in buildings and achieve comfortable visual environments, especially in the workplace. Yet large inter-individual variabilities in glare perception remain unexplained and thus uncovered by the current empirical glare models. We hypoth...

When studying discomfort glare, researchers tend to rely on a single questionnaire item to obtain user evaluations. It is unclear whether the choice of questionnaire item affects the distribution of user responses and leads to inconsistencies between studies. This study aims to investigate if different glare questionnaire items yield similar distri...

Current view representation methods in VR predominantly rely on static photographs and tone-mapping operators without temporal variations, limiting the exploration of dynamic features in a view. This study presents an alternative workflow to capture dynamic daylit views in VR by utilizing real-time videos and the camera's automatic tone-mapping pro...

This study explores the effect of multiple bright light sources in the field of view on discomfort due to glare in office environments. User experiments were conducted in semi-controlled dim daylit environments mimicking open-plan offices, with glare stimuli varying in size, number, and position. The findings suggest that being exposed to several b...

Current view representation methods in VR predominantly rely on static photographs and tone-mapping operators without temporal variations, limiting the exploration of dynamic features in a view. This study presents an alternative workflow to capture dynamic daylit views in VR by utilizing real-time videos and the camera's automatic tone-mapping pro...

Previous studies have shown that access to a satisfactory view to the outside with sufficient daylight is essential for building occupants' health and well-being. It has also been suggested that certain features of visual content improve view-out quality, such as horizontal stratification, natural landscapes, distant features, and diversity of visu...

To address the current gap in view-out research, this study aims to develop a workflow able to accurately capture dynamic views in an experimental setting. In testing the suitability of the proposed methodology, we conducted two comparative studies on the participants’ perceptual impressions using VR. In the first experiment, participants (N=34) we...

Recently, there have been multiple proposals for faster methods to calculate glare metrics, daylight glare probability (DGP) in particular. This is driven simultaneously by the lengthy times required to simulate DGP with a conventional image-based approach and accumulating evidence from subjective glare evaluation experiments showing that accountin...

A recent study on the glare protection performance of electrochromic (EC) glazing showed that visible transmittance levels lower than 0.6% are necessary to achieve comfortable situations for sun positions, that were close to the central field of view. However, the question that arises is how often such situations occur throughout the year and how t...

Occupants' visual comfort in an indoor space strongly depend on the quantity and quality of the daylight inside the space which can be altered with the type of window glazing. In this study, we compared the visual comfort perception of participants with sun in their field of view under two types of glazing: color-neutral and blue-tinted electrochro...

Providing adequate glare protection and a view to the outside through fabric shading devices is challenging because these two objectives require conflicting material properties for a fully lowered shading. In a semi-controlled office-like experiment involving 32 participants, we investigated four types of neutrally-colored fabrics (charcoal and gra...

High-technology glazing panes are designed to meet the need for natural light, while optimizing key functions such as reducing solar heat gain in spaces and/or redirecting daylight to the rear of the spaces. However, the actual performance in terms of both illumination and glare protection of these glazing systems is often unknown. This study aims...

The importance of access to a view to the outdoors and exposure to daylight through a window on the health and well-being of building occupants has been recognised in the fields of building science and environmental psychology. Especially for urban citizens who spend most of their time indoors, the long-term health implications for having a quality...

The spectral sensitivity of the average human eye in photopic conditions is represented by the photopic luminosity function V (λ). The CIE has established the photopic luminosity functions for the 2 o and 10 o visual fields for a standard observer applicable for foveal and para-foveal light sources, respectively. These functions differ in short wav...

This paper provides a validation of a novel sampling, storage, and evaluation method named raytraverse that can quickly and accurately compute glare and visual comfort metrics including vertical illuminance (Ev), Daylight Glare Probability (DGP), and Unified Glare Probability (UGP). The motivation is to provide a path towards understanding the spat...

Defining indoor environmental conditions that meet the needs and preferences of occupants in open space offices can be challenging since the same space might be occupied by people with different individual needs and preferences regarding what constitutes a comfortable work environment. This study presents outcomes of a set of longitudinal point-in-...

Existing research on user's satisfaction at the workplace have shown that occupants' perceived comfort depends on a number of environmental and non-environmental factors and that forgiveness, meant as the indulgent attitude towards inadequate indoor environmental conditions, becomes an essential element in the ultimately rated level of appreciation...

Discomfort glare metrics typically consider at least one of the two effects of discomfort glare-saturation and contrast-in their equation. The former occurs when there is an excessively bright glare source in the field of view, while the latter occurs when there is a high luminance ratio between the glare source and the adaptation level of the eye....

Building Performance Simulation (BPS), a useful tool to assess the operational performance of buildings and systems, can often be computationally expensive. The use of BPS is cumbersome for problems where the speed of response is important, e.g. real-time control, uncertainty quantification, parametric exploration, or stock modelling. Emulators, su...

Façades and light pattern composition have been shown to influence the spatial experience and physiological responses of humans [1,2]. The present study examines the effect of sunlight penetration and window size on fixations to the floor of the scene, and the relation between visual interest and fixations in an experiment using 360° scenes display...

Current discomfort glare prediction metrics usually account for at least one of the two categories of effects that induce discomfort glare – the saturation and contrast effects. Saturation-driven metrics (overall illuminance on the eye) are suited for brightly lit scenes in general. On the contrary, contrast-driven metrics (luminance ratio in the f...

This paper analyzes the relative distribution of annual saturation and contrast effects of discomfort glare in a deep open-plan office. A previous comparative study has shown that while hybrid glare metrics were found to predict glare well in most scenarios occurring in the investigated datasets, contrast-driven glare metrics predict discomfort gla...

We propose a new method for climate-based daylight modeling (CBDM) based on simulating and evaluating only the most important features. By adaptively sampling the temporal lightfield that describes daylight in buildings, our method escapes the curse of dimensionality that binds typical approaches. The method is centered around an iteratively guided...

Directional sampling approach to reduce simulation and data requirements for accurate daylighting simulation: https://youtu.be/slXjIQKGK3k?t=17782

The size of window openings is widely acknowledged as an important factor in our spatial perception. However, little is known about how the perception and preference of windows changes between countries, leaving a gap of knowledge regarding the applicability of research findings across latitudes. This article presents the outcomes of a study invest...

A significant corpus of research has shown that occupant behaviour is a key factor of uncertainty when predicting building energy use. Building occupants affect energy use directly and indirectly by regulating their indoor environment according to their comfort criteria and a wide range of contextual, psychological or social factors. Increasing res...

Daylight provision to the indoor space is affected by different building elements that cannot be fully controlled by the users, such as the window size of a space. The dimensions of the fenestration not only affect the lighting levels, but they also affect how the space is perceived by its users. The present study examines three different window si...

This paper presents the combined effect of indoor temperature (19 °C, 22 °C, and 26 °C) and colored glazing (blue, orange, and neutral) on visual perception of daylight. Experiments were performed in an office-like test room, in which 75 participants were fully immersed under visual and thermal stimuli. Findings are discussed in terms of cross-moda...

Objective Temperature–color interaction effects on subjective perception and physiological responses are investigated using a novel hybrid experimental method combining thermal and visual stimuli from real and virtual reality (VR) environments, respectively. Background Despite potential building design applications, studies combining temperature w...

A well daylighted space can provide a highly satisfying visual environment. However, if that environment causes us visual discomfort, it can become such a nuisance that we, sometimes literally, turn our backs on this powerful connection to the outside world. Given this, there is enormous value in quantifying the occurrence of discomfort glare withi...

Environmental performance objectives in terms of energy consumption and carbon emission targets can be found in various building norms and certifications schemes. These targets are often dependent upon the building program (e.g. office), but independent from its context; the same value is imposed for two buildings of the same program regardless of...

Adaptive kinetic façades are systems capable of modifying their shape to optimize their behavior regarding real time outdoor and indoor conditions. They are typically evaluated based on quantifiable physical parameters such as illuminance levels, with little attention-for lack of evaluation criteria-given to subjective appreciation of the façade an...

This paper investigates the impact of transmittance level and layout variations of semi-transparent photovoltaics (STPV) on both energy performance and occupancy-based visual and thermal comfort, simulating a reference office with a fully south-oriented glazed surface. Four transmittance levels (20, 30, 40 and 50%) were investigated, first uniforml...

Daylight is valued as an energy efficient alternative to electric light and over the past few decades, climate-based horizontal illuminance metrics have demonstrated the importance of variable sky conditions on annual predictions. These metrics allow us to evaluate a building as an ensemble of spaces that can achieve a pre-set performance target. I...

This paper details the results of an experimental study investigating the combined effect of indoor temperature (19 °C, 23 °C and 27 °C) and horizontal illuminances (~140 lx, ~610 lx and ~1440 lx) on visual perception, with daylight as the only source of light. The goal is to evaluate the cross-modal effect of temperature and the unimodal effect of...

Within the scope of a broader research project about daylight and temperature interaction effects on human responses, this paper investigates how daylight transmitted through spectrally selective glazing (blue, orange and a reference neutral) affects thermal comfort of occupants (cross-modal effect of daylight colour), besides the more conventional...

Voluntary green-rating systems exist in different forms worldwide to certify the sustainability of residential and commercial buildings and help national policies promote energy-efficient design practices. Despite the general assumption that sustainable buildings also provide high comfort and healthy conditions, existing studies on green-rated buil...

This study investigates the joint impact of façade geometry and associated sunlight patterns on occupant subjective perception and physiological responses through a novel experimental method coupling physically-based simulations shown in virtual reality with a wearable biometric device. A total of 72 subjects participated in a study combining three...

Façade design is claimed to fulfil a number of requirements in workplaces, ranging from privacy to safety and from comfort to aesthetics. For future R&D efforts in façade design, identifying the key drivers that should shape contemporary facades in office buildings is not always an easy task because of the discrepancies that can emerge between the...

The built environment is facing environmental regulations more ambitious than ever before. In Europe, a law will lead all new buildings to the Nearly Zero-Energy performance level. However, even if a building does not have any energy consumption for its operation phase, it still has embodied impacts. To that end, Life-Cycle Assessment (LCA) methods...

This paper presents two different approaches to deal with the assessment of the BIPV potential in building renovation projects in urban areas, taking Neuchâtel as a representative middle-size city of the Swiss plateau. 1) A building-scale analysis aiming to show to stakeholders involved in the renovation process that it is important to consider BIP...

PV installations on flat roofs offer a wide range of design options, which are usually neglected in urban-scale assessments as these typically assume horizontal or other fixed arrangements. In this study, we analyse the influence of common design parameters (tilt and inter-row distance) in evaluating the potential of PV arrays installed on flat roo...

In our daily lives we are exposed simultaneously to multiple sensory stimuli, such as visual, thermal, acoustic and olfactory. Experienced together, they shape our perception of the environment and determine our comfort. In indoor environments, stimuli are affected by construction features such as material, openings, form, size and colour. However,...

Daylight has an undeniable value in various aspects of architectural design, ranging from energy efficiency and user comfort to our experience of space. Even though there is substantial evidence of the positive effects of daylight access on occupants, we have limited knowledge on how the façade geometry and the spatial composition of the resulting...

Daylight has an undeniable value in various aspects of architectural design, ranging from energy efficiency and user comfort to our experience of space. Even though there is substantial evidence of the positive effects of daylight access on occupants, we have limited knowledge on how the façade geometry and the spatial composition of the resulting...

The increasing interest in solar energy production in urban areas requires an accurate simulation of solar irradiation on building surfaces, including vertical surfaces. However, solar potential analyses are usually conducted on 2.5D models, which are limited to roof surfaces. Methods based on 3D models, instead, allow the simulation of solar radia...

The purpose of this report is to detail the findings of a long-term evaluation study on the impact of installing electrochromic glazing in two different buildings owned by Audemars Piguet. The two locations under investigation are the APRP ateliers in Le Locle (May 14-16 and July 03-05, 2018), and the AP bureaux in Le Brassus (June 25-27 and August...

This contribution introduces an experimental study aiming to provide concrete evidence on how façade and daylight pattern geometry can affect the emotional responses triggered by a space. The study was conducted in Virtual Reality (VR) where participants were exposed to 360° scenes of an interior space with three different façade patterns. Their su...

A variety of building labels and norms exist that set evermore-ambitious environmental and energy performance targets. In parallel, a growing number of building performance evaluation tools are adopting the life-cycle assessment (LCA) methodology to allow verifying if a project, based on its detailed description, reaches these targets. However, suc...

Due to climate change, the built environment is facing increasingly strict environmental targets. Thus, architects are challenged to design evermore high-performing buildings, a task for which they can no longer depend solely on their experience and intuition. Building performance simulation (BPS) tools have become central in this context to suppor...

Neighborhood form and building facade design are key drivers of indoor daylight performance. Architectural design at the neighborhood scale starts with massing scheme proposals and other design specifications including façade design are typically enriched sequentially in subsequent design stages. In this study, we simulate multiple pairs of early d...

Within the scope of a broader research project about visual and thermal interaction effects on human comfort and perception, the aim of this paper is to study the variation of thermal, visual and overall comfort votes of people exposed to blue and orange glazing. The study, conducted in a controlled test room and involving a total of 75 participant...

Findings from neuroscience are increasingly interwoven with architectural research. Understanding physiological responses to environmental stimuli in the built environment are critical when evaluating occupant health and wellbeing. Research in the field of photobiology has shown that lighting conditions can significantly alter our circadian rhythms...

Many municipalities and public authorities have supported the creation of solar cadastres to map the solar energy-generation potential of existing buildings. Despite advancements in modelling solar potential, most of these tools provide simple evaluations based on benchmarks, neglecting the effect of uncertain environmental conditions and that of t...

Due to the growing popularity of virtual reality (VR) as a tool for conducting subjective experiments, we propose a session addressing methodological concerns and good practices for the use of VR in lighting research, going further than a simple demonstration of immersive scenes. In view of the emergence of this technology as an experimental tool i...

This paper introduces an interactive web-based visualizer for multi-metric daylight simulation results, named OCUVIS. It is able to display simulation-based results for a diverse range of ocular human-centric metrics such as non-visual health potential (nvRD), daylight-related visual interest (mSC5) and visual comfort (DGP with Ev), as well as hori...

The objectives of this study are to evaluate (1) direct non-visual effects of red-impoverished daylight on circadian resetting and alertness and (2) the daily light-exposure pattern on indirect–circadian–effects. The novelty of this study is that it will be conducted on the EPFL campus in two identical classrooms outfitted with electrochromic windo...

One of the effects of globalization and work mobility is the increasing multiculturalism in the workplace. While contemporary design policies for energy efficiency and comfort regulations are moving towards the adoption of models customized for local communities, consideration on the coexistence of people with different origins is underestimated in...

This paper evaluates the influence of light levels (i.e., illuminance) on subjective thermal perception of people, distinguishing between thermal sensation and thermal evaluation. The goal is to investigate whether reported effects found by other studies in controlled environments can be observed in real-life contexts and to understand if results a...

[This article is available for free until end of May 2018 at this address: https://authors.elsevier.com/a/1WsTL1HudMvutv] The need for adequate instruments to support practitioners toward achieving sustainable and energy-efficient architectural and urban design has long been acknowledged. Motivated by identified shortcomings of building performanc...

This paper presents a novel experimental method which uses a Virtual Reality (VR) headset, aiming to provide an alternative environment for the conduction of subjective assessments of daylit spaces. This method can overcome the difficulty of controlling the variation of luminous conditions, one of the main challenges in experimental studies using d...

fulltext here: https://infoscience.epfl.ch/record/233642?ln=en

fulltext here: https://infoscience.epfl.ch/record/232380?ln=en

Access to daylight in buildings is the combined effect of a building's own physical attributes along with its surrounding physical context. There is thus growing interest among researchers to extend the use of building performance simulation (BPS) tools for daylight performance evaluation, not just for an individual building, but to the neighborhoo...

Le potentiel solaire a une importance primordiale dans la performance énergétique des bâtiments, car le soleil est normalement la principale source d’énergie renouvelable à disposition en milieu urbain. Pourtant, le potentiel solaire n’a pas une définition univoque. Comme nous l’avons déjà vu dans les précédents ouvrages de cette série, il est poss...

This paper introduces an experiment using a virtual reality headset to collect subjective evaluations of rendered daylit architectural scenes. By varying sky conditions and view directions from a fixed view position, the authors collected subjective perceptual ratings from architectural renderings and compared them to image-based measures related t...

In this paper, we present an emulator of a building-energy performance simulator. Previous work on emulators for this application has largely focused on linear models. Since the simulator itself is a collection of differential equations, we expect non-linear models to be better emulators than linear models. The emulator we present in this paper is...

This study presents a methodology for evaluating the effects of simultaneous temperature and illuminance set-point variations on energy consumption. Different illuminance levels are achieved with an innovative dynamic shading control algorithm that allows keeping constant values of maximum workplane illuminance. Findings from applying the methodolo...

The increasing popularity of parametric design tools goes hand in hand with the use of building performance simulation (BPS) tools from the early design phase. However, current methods require a significant computational time and a high number of parameters as input, as they are based on traditional BPS tools conceived for detailed building design...

Although fabrics are widely used as shading devices, reliable simulation models are rather rare and therefore the choice of a fabric with appropriate material characteristics is difficult. This paper presents a simulation model, which can be applied to most of the common available fabric shading materials. Furthermore a comprehensive simulation stu...

The education of building practitioners is challenged by the increasing need for interdisciplinary profiles in the professional practice. To progress toward the goal of a sustainable built environment, a common language must be shared among fields such as architecture and engineering, between which persisting barriers remain. This paper presents an...

This paper describes the preliminary findings of a post-occupancy evaluation campaign conducted on contemporary and energy-efficient office buildings with different façades treatments. The aim is to investigate occupants' comfort and perceived productivity and to observe to what extent the space appearance and the façade design play a role in the u...

Although knowledge about the impact of light on individuals beyond vision is becoming substantial and less and less controversial, there is still a gap on how to properly address what type of lighting quality one should seek in an indoor space. What constitutes good lighting conditions from a truly holistic, human-centered perspective, i.e. encompa...

This paper will present an annual simulation-based workflow for assessing human perceptual and non-visual responses to daylight across a series of view positions in an architectural case study. Through the integration of mathematical models used to predict visual interest and non-visual health potential, this paper will introduce an automated workf...

This poster introduces the methodology and main findings so far in Kynthia Chamilothori’s PhD thesis, regarding the use of virtual reality as a substitute for experiments in the real space, and the investigation of how facade characteristics influence the perception of a daylit space.

Despite recent developments, neighborhood-scale performance assessment at the early-design phase is seldom carried out in practice, notably due to high computational complexity, time requirement, and perceived need for expert knowledge, ultimately limiting the integration of such a task into the design process. In this paper, we introduce a predict...

The presence of vegetation can significantly affect the solar irradiation received on building surfaces. Due to the complex shape and seasonal variability of vegetation geometry, this topic has gained much attention from researchers. However, existing methods are limited to rooftops as they are based on 2.5D geometry and use simplified radiation al...

This paper introduces a novel approach for the assessment of daylight performance in buildings, venturing beyond existing methods that evaluate 2-dimensional illumination and comfort within a fixed field-of-view in order to predict human responses to light concerning non-visual health potential, visual interest, and gaze behavior in a visually imme...

This paper proposes randomly-generated synthetic time series incorporating climate change forecasts to quantify the variation in energy simulation due to weather inputs, i.e., a Monte Carlo analysis for uncertainty and sensitivity quantification. The method is based on the use of a small sample (e.g., a typical year) and can generate any numbers of...

Thermal building simulation currently uses Typical Meteorological Year (TMY) data to guide the design decision-making process or for compliance with energy standards. TMY data usually excludes extremes and in many cases are gathered from microclimatic contexts that are not sufficiently representative of the project sites (e.g., airports), adding un...

Despite recent developments, the need for adequate guidance and support in the early decision-making process of urban planners, designers, and architects has recurrently been recognized. Traditional performance assessment methods, which are often based on partial and independent dynamic simulations evaluating individual metrics, are better suited f...

The need for sustainable architecture and urban design and planning has long been acknowledged, along with the necessity for adequate, early-phase guiding instruments. This paper aims at exploring the effectiveness and usability of a novel decision-support workflow for neighbourhood-scale projects, developed to provide practitioners with early-stag...

Daylit architecture is perceived as a dynamic luminous composition, yet most existing performance metrics were designed to evaluate natural illumination for its ability to adequately illuminate a two-dimensional task surface and avoid glare-based discomfort. It may be argued that task-driven approaches based on surface illumination and glare ignore...

The evaluation of indoor comfort requires a thorough understanding of how human occupants perceive four indoor environmental factors: visual conditions, air quality, acoustic ambience and thermal conditions. Recent studies have found that overall comfort is more than the average effects of these four parameters. Beside their main effects, their mut...

In spaces where daylight is a primary source of illumination, our visual perception of architecture is largely influenced by the ephemeral composition of sunlight and shadow. To evaluate these perceptual effects, the authors will apply quantitative contrast measures to HDR renderings for a series of existing contemporary architectural spaces under...

The aim of this paper is to provide a systematic understanding, through simulation-based assessment, of how contemporary urban planning affects the bioclimatic features of existing historic architecture. An emblematic early 20th century Brazilian building, the Casa das Rosas in São Paulo, has been chosen as a case study to see how the deep transfor...

This paper proposes randomly-generated synthetic time series incorporating climate change forecasts to quantify the variation in energy simulation due to weather inputs, i.e., Monte Carlo analysis for uncertainty and sensitivity quantification. The method is based on the use of a small sample (e.g., a typical year) and can generate any numbers of y...