In the last decades, several studies aimed at assessing some specified aspects of visual comfort characterizing the relationship between the human needs and the light environment, such as an ...available amount of light, light uniformity, light quality in rendering colors, and predicting the risk of glare for space occupants. For each of them, a (still growing) number of indices and metrics have been proposed in the literature and standards. In the present work, they are described, categorized according to common features, and finally discussed. As in the case of long-term thermal comfort indices, such visual comfort indices and their summation over a specified calculation period might be used for driving optimization processes to support a more conscious integrated design of buildings. To that purpose, the choice among the available visual comfort indices needs to be informed by an analysis of their features and implications. We present recommendations for use, and suggest areas where improvement is needed for their use in optimization processes to support buildings׳ design.
In this work, thermal and visual comfort of low heat loss switchable suspended particle device-vacuum (SPD-vacuum) glazing was investigated for less energy-hungry adaptive building’s glazing or ...façade integration at temperate climate. This SPD-vacuum glazing had 38% visible transmittance in the presence of 110 V applied an alternating voltage and 2% visible transmittance in the absence of electrical power. Outdoor test cell characterisation was employed to measure the thermal and daylighting parameters of this glazing. Solar heat gain or solar factor was calculated using non calorimetric methods and varied between 0.38 (Switch OFF/opaque) to 0.51 (Switch ON/transparent). Test cell indoor and ambient parameters (incident solar radiation and ambient temperature) were engaged for thermal comfort analysis by using PMV and PPD methods. Visual comfort was analysed from glare potential, useful daylight index, and colour properties. The comfortable thermal environment was attainable using both states of this glazing for a clear sunny day. Acceptable daylight throughout the day was possible for a clear sunny day for opaque state; however clear state offered allowable/comfortable correlated colour temperature (CCT) of 5786.18 K and colour rendering index (CRI) of 94.83.
•Spectral measurement of combined suspended particle -vacuum glazing provided 38% transmission while 110 V AC was supplied.•Thermal comfort of suspended particle device-vacuum combined glazing was evaluated using PMV and PPD methods.•Visual comfort was calculated using useful daylight, daylight glare and colour properties.
•Introducing smart window technologies and thermochromic glazing.•Materials developed for use as thermochromic glazing.•Simulation tools used for performance evaluation.•Evaluation of building energy ...saving through experiments and simulation.
Thermochromic window technologies promise pioneering architectural windows with energy-saving capabilities through the intelligent regulation of indoor solar irradiation and modulation of window optical properties in response to real-time temperature. Thermochromic glazing has been thoroughly advanced from a materials perspective, with many kinds of thermochromic coating techniques developed thus far, however, a far smaller body of work exists to investigate how these kinds of glazing would perform within buildings. This paper presents a systematic review of these thermochromic films, coatings and glazings that have been used to analyse primarily energy saving capability in buildings, using computer simulation as well as full-scale models. Research from 2009 to 2019 was obtained from architecture and engineering databases, identifying window types modelled, energy savings found, and comfort analyses conducted. Thermochromic windows were reported to have the potential to save heating and cooling energy demand from 5.0 to 84.7%, in comparison to plain glass and dependent on climatic conditions. Differences in energy saving capability were analysed based on location and glazing type. Thermochromic window energy performance was found to vary significantly between different cities using the same film type (up to 73.4%), but far less so between different films types used in the same city (up to 21.6%). Few studies were shown to have explored thermochromic windows from a visual and thermal comfort performance perspective. This paper highlights areas of guidance for future studies of thermochromic glazing for energy-efficient building applications to better forecast energy saving performance of thermochromic windows for real building application.
Light is an important element in human life. Without lighting, humans cannot see an object visually. It is from the reflection of the light of these objects that humans visualize shapes clearly and ...see comfortably. The coffee shop as a public space certainly requires adequate lighting so that visual comfort is maintained. Visual comfort will be achieved if the terms and conditions for achieving visual comfort have been fulfilled, including the brightness level according to the recommended standards and the distribution of lighting according to the spatial layout according to the standards. With the aim to determine the natural and artificial lighting conditions in coffee shops and lighting standards for visual comfort, this study will use a comparative research method. Where this method compares lighting standards with research results. The results of this research are that the level of light intensity found outside and inside the building meets the SNI standard at 250 lux by taking data that has an average lux during the day and lux in the afternoon. The conclusion from this study is that BENING coffee & space on one of the visual comfort factors has met the visual comfort standards set by the SNI.
We examine the influence of street scales (the street width, building height, and street-width-to-building-height ratio, referred to as ‘width-to-height ratio’ in the paper) on visual, acoustic, and ...audio-visual comfort evaluation (as evaluated by a set of participants) in urban areas. In addition, we examine the relationships between the sound level and the abovementioned subjective comfort evaluation except the visual one. After measuring the street scales and recording the street visual information with a 3D camcorder, the virtual 3D models of the streets were generated. Meanwhile, dual-channel acoustic signals of the streets were collected. Subsequently, subjective tests were carried out using a 3D virtual reality with corresponding sounds using 164 participants. The analysis shows that subjective attitudes are directly related to the street scales. In particular, there is a strong positive correlation between audio-visual comfort and the street width-to-height ratio. In contrast, the three indicators (visual, acoustic, and audio-visual comfort) are strongly negatively correlated to the height, and this type of negative correlation is also observed between subjective indicators (except the visual one) and the sound level. Overall, the respondents found the audio-visual level most comfortable when the street width-to-height ratio is greater than 1, street width is within 20 m, height of street buildings is less than 26 m, and the sound level is less than 58 dBA. It is expected that these findings can aid designers in predicting the ideal audio-visual environment quality for urban streets.
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•The correlations between psychological stratification and urban environments examined.•Visual comfort positively correlated with W/H, negatively correlated with H.•Acoustic comfort negatively correlated with W, H, and SL.•Audio-visual comfort positively correlated with W/H, negatively correlated with both H and SL.•A high quality of audio-visual comfort for urban environments achieved by varying the street scale.
One of the top priorities in the building design process is minimizing energy consumption. Moreover, the level of occupants' comfort directly affects their learning ability Therefore, this paper uses ...a multi-objective approach to optimize the architectural design features, including some newly examined ones, that define the geometry of a classroom. Furthermore, to create a practical methodology for minimizing lighting energy demand, we put the technique of dividing the class into independent, controllable lighting zones into practice for the first time. This research aims to introduce an optimized primary school classroom that meets both inhabitants' comfort needs and energy efficiency. For this, we first developed a parametric model using the Grasshopper plug-in for Rhino. Afterward, the environmental plug-ins of Honeybee and Ladybug were employed to evaluate energy performance and thermal comfort and find optimized solutions. The last step was assessing the occupants' visual comfort for each of these optimized solutions and selecting the final optimum designs. This two-phase optimization procedure has led to the reduction of total energy demand, up to 47.92 kWh/m2, and improvement of occupants' thermal and visual comfort. The results show that the proposed methodology can provide designers with a guideline for designing a sustainable classroom that fulfills their preferences as well as encouraging them to use innovative ways for energy conservation.
Differences in visual comfort between comfortable and uncomfortable luminance were explored on a smartphone. The results revealed that tiny changes in CFF and microsaccade parameters (pupil diameter, ...amplitude, and peak velocity) were presented at the comfortable luminance, inducing less eye discomfort. Particularly, CFF is an effective indicator of visual comfort and fatigue.
•We did the energy and visual comfort analysis of an office building.•We examine different glazings and its impact on energy and visual comfort.•Low-E glazed windows with automated blinds improve ...visual comfort in office buildings.•Increasing daylight provision will increase energy savings without visual comfort.
In hot climates, the exterior envelope of office buildings can significantly contribute to the building's energy consumption. Windows are considered as a major source of heat gain and can contribute to the reduction of energy when daylighting is integrated with artificial lighting. However, with daylighting, the possibility of visual discomfort is likely to arise due to the uncontrolled light. The present study focuses on investigating the energy savings when daylight and artificial light are integrated while maintaining visual comfort. In order to assess visual comfort, both glare index and DaylightFactor are studied. A typical office in a hot climate is modeled using the simulation program, DesignBuilder. We predict the energy and visual performance for three different types of glazed windows. For all types of modeled windows a significant reduction in the annual cooling and building energy consumption was observed. For example, a 14% reduction in total building energy consumption was obtained with daylight integration for the double-glazed clear glass windows and a 16% reduction was obtained for double-glazed low-E windows. It has been observed that in all cases visual comfort was not achieved. By employing automatic interior shading control, visual comfort was achieved with no significant reduction in energy savings.
Differences in visual comfort between comfortable and uncomfortable luminance were explored on a smartphone. The results revealed that tiny changes in CFF and microsaccade parameters (pupil diameter, ...amplitude, and peak velocity) were presented at the comfortable luminance, inducing less eye discomfort. Particularly, CFF is an effective indicator of visual comfort and fatigue.