Search

Research has shown that glazed buildings can have higher energy use and are more prone to overheating than other types of buildings. However, few studies have explored the performance of glazed buildings in cold climates. This article aims to evaluate the energy and indoor thermal performance of a high-rise residential building with glazed façades and balconies under Nordic climatic conditions, through a parametric study. Dynamic, whole-year simulations are used to evaluate the impact of four design parameters (with and without glazed balconies, type of balcony glazing, window to wall ratio, and building location within the Nordic region) on the energy and indoor thermal performance of the building. The results show that the building without glazed balconies outperformed that with glazed balconies. Changing from single- to double-pane glazing also helped to reduce energy use and overheating, as did lowering the window-to-wall ratio. Overheating of apartments was found to occur during the summer in five of the six locations simulated, which suggests that solar control strategies might be needed for glazed buildings even in a Nordic climate. This study highlights the importance of further research on glazed residential buildings, which are becoming more common in contexts subject to such climates.

Copyright of PARC Pesquisa em Arquitetura e Construção is the property of Universidade Estadual de Campinas - Portal de Periodicos Eletronicos Cientificos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Thermochromic glazing properties have been measured under variable temperature conditions with customized spectrophotometer. • Procedure for thermochromic thin film preparation has been presented. • Building energy simulation has been implemented for impact assessment. • Optimization of the thermochromic properties has been performed for different climates. • A complete procedure for thermochromic design and optimization has been described. Thermochromic (TC) glazing could provide a significant reduction of energy consumption in curtain wall buildings. However, each application requires a design tailored to building's specifications. This paper proposes a complete approach for designing TC glaze based on building energy simulation starting from the production of thin thermochromic layers and the measurements of their optical properties by means of a customized spectrophotometer. The main focus of this work is to identify the optimal TC optical response that minimises the building energy consumption. Energy simulations have been performed for a virtual mock-up set at two locations with different climates, Italy and Poland. A set of profiles, each one determining thermochromic properties in terms of switching temperature, range of solar transmittance and transition speed, have been created with a fine step of temperature (2 °C) and used to simulate different scenarios. The outcome of the optimization provided the optimal properties to achieve the right balance between cooling energy reduction and heating energy increase due to the application of the thermochromic layer, in comparison to a standard clear glass. The fine step in switching temperature allowed to accurately estimate the subtle differences for the two different climates (25 °C Italy, 24–26 °C Poland). The highest impact has been found for the Italian location with a maximum reduction of total energy consumption of 22.8%. This was achieved with a thermochromic switching at 25 °C, with fast transition and range of transmittance between 0.1 (switched state) and 0.5 (normal state), which is a not extreme behaviour. [ABSTRACT FROM AUTHOR]

This paper deals with energy efficient glass in office buildings in Amman city. The objectives of this paper are to understand the role of efficient glass in reducing lighting, heating, and cooling demands and the amount savings to achieve. In addition to suggest main guidelines to follow when designing glazed office buildings for architects and stakeholders, the evaluation of thermal and daylighting performances for a glazed building in Amman was performed by Ecotect and some equations. The reductions in lighting, heating, and cooling loads and energy cost were evaluated through a comparative simulation among three glass types considering four optical and thermal variables: U-value, visual light transmission (VLT), solar heat gain coefficient (SHGC), and solar coefficient (SC). Results show that the basic factors to enhance buildings energy behavior are: building location and the availability of solar radiation at the selected location. In addition to the building orientation and glass optical and thermal properties, the energy efficiency of buildings increases when the building orientation is between 125° and 235°, and the installed glass has U-value less than 1.5 Wm2/k, VLT between 20% and 50% and SHGC and SC less than 0.2. The implementation of these properties reduced the building electricity cost for lighting, heating, and cooling by 45%-53%.

The aim of this paper is to explain how the design intent of a bespoke glazed façade develops from the point of view of the façade consultant BIFF SA. The explanation of this concept development is not only interesting because of the different phases of the process, but also because of the unusual specifications and demands established by the architects and the Client, and for the project evolution trough several technical solutions up to final project state. During the concept development materials like stone, steel, aluminum or fabric are normally combined with glass. This challenging glazed façade has been developed for a luxury villa in Switzerland where a triple laminated glass cladding has been selected as the final most suitable solution for creating a building envelope with glass panes of 3000mm W x 7000mm H bonded to a back frame with structural silicone. These units have obviously aesthetic requirements and also different functional applications and the solution should fulfill all demands and do not the technical aspects of building up a façade with such a big glass units.

Abstract Light pollution has been recognised as a major environmental problem in urban areas at night. This study presents an investigation into the impact of seven various shading solutions on the risk of light pollution caused by indoor artificial lighting in a fully glazed office building. Radiance, a ray-tracing package, was adopted to calculate external illuminances produced by indoor lighting applications at various positions. It has been determined that: 1) A glazed façade could become a critical source of light pollution or obtrusive light (sky glow and light trespass) due to applications of indoor lighting at night; 2) A light shelf could perform well on the protection of both light trespass and sky glow; 3) A large overhang and horizontal louvre could effectively lower the risk of light trespass, but would possibly cause the deterioration of sky glow; and 4) No significant impact of short overhang and vertical louvre can be found on the two aspects of light pollution. This study exposes a significant implication; apart from their principal functions, the shading devices applied in a largely glazed building may require a new role in controlling obtrusive light in cities at night. Highlights • Investigation of night light pollution risk of glazed buildings in cities. • Impact of various shading solutions on the emitting light from glazed facade. • Ray-tracing analysis of intensities and distributions of the artificial lighting. • Comparisons of upward light and light trespass risk between various shading solutions. • Recommendation of shading applications in terms of light pollution in glazed buildings. [ABSTRACT FROM AUTHOR]

The inadequacy of highly glazed facade office buildings has been debatable for decades due to their impact on the internal environment comfort and energy consumption. One of the consequences noticed in the 50′s decade was the thermal discomfort caused by the non-uniform thermal environment. Despite the glass technology developments since then, buildings with ordinary laminated glass and unknown thermal properties became commonly accepted in Brazil's most populated cities in the low latitudes, opposing primary design recommendations. This work discusses this context based on the short-term thermal assessment of five case studies in a warm and humid climate, assuming regular occupation. The combination of the walk-through audit with thermal monitoring at the centre of office rooms and next to the facade resulted in comparing air and operative temperatures, and the PMV index, under different environment configurations. Surface temperature measurements with thermographic photos complemented the thermal analyses. The case studies confirmed different simultaneous thermal sensations between perimeter and centre zones. The perimeter zones barely reach PMV 0.5, achieved by the users' adaptations that mitigated the thermal radiation from the facades, obstructing the windows with internal shades or avoiding the window view by changing the layout. Therefore, the extensive use of window obstructions compromises other indoor environmental aspects, such as daylighting and exterior view, contradicting the architects' expectations of a transparent glass building. [ABSTRACT FROM AUTHOR]

The aim of this study is to show the critical aspects of a completely glazed high rise office building from an energy efficiency point of view in different European climates. The achievable consumptions and the most influential parameters such as glazing U-value, VT/SHGC and shading and their optimal values were investigated. The study has been carried out for a theoretical office building in Italy and Lithuania, representatively of a southern and northern EU climate. The building chosen is representative of all the glazed-simple shape buildings and the analysis of the entirety of the building enables a clear and im-mediate outcome of global consumptions. Number of DesignBuilder simulations were performed and the annual consumptions are summed with the primary energy criteria. Results show the critical aspects of 100% WWR buildings: in the coldest climate the main problem is the huge surface of relatively high glass U-value compared with standard walls, while in the warmer one the main efforts need to be done to avoid the summer overheating caused by incoming solar radiation. Finally, it is shown that it is difficult to lower the overall primary energy consumptions below 130 and 140 kWh/m2a for North-Italy and Lithuania locations respectively. The analysis is focused only in the envelope parameter, thus it is not included renewable energy systems, which can generate higher energy efficiencies. Santrauka Straipsnyje pateikiamo tyrimo tikslas – parodyti kritinius daugiaaukščių administracinių pastatų su dideliais įstiklinimo plotais atitvarų charakteristikų aspektus energinio efektyvumo požiūriu esant skirtingam klimatui. Buvo tiriami labiausiai įtaką energiniam efektyvumui darantys parametrai – šilumos perdavimo koeficientai U, šviesos ir visuminio saulės energijos praleisties koeficientų santykis VT/SHGC bei apsaugos nuo saulės priemonės ir optimalūs jų dydžiai. Buvo atliekama teorinio administracinio pastato Italijoje ir Lietuvoje analizė. Šios vietovės buvo parinktos Europos pietiniam ir šiauriniam klimatui reprezentuoti. Parinktas pastatas yra tipinės nesudėtingos formos, su visiškai įstiklintais fasadais. Pastato charakteristikų įtaka vertinama kompleksiškai modeliuojant pastato metinius energijos poreikius taikant DesignBuilder programą, vertinimo kriterijus – metiniai pirminės energijos poreikiai. Rezultatai parodė, kad pastatui su 100 % fasado įstiklinimo plotu nustatyti kritiniai aspektai yra: esant šaltam klimatui pagrindinė problema yra dideli atitvarų plotai, kuriems būdingas sąlygiškai didelis šilumos perdavimo koeficientas, lyginant su neskaidriomis atitvaromis, o esant šiltam klimatui reikia dėti pastangas, kad būtų sumažinti milžiniški šilumos pritėkiai, atsirandantys dėl saulės. Straipsnyje parodyta, kad vien optimizuojant atitvarų charakteristikas sudėtinga pasiekti metinius pirminės energijos poreikius, mažesnius nei 130 ir 140 kWh/m2, esant Italijos ir Lietuvos klimatui atitinkamai. Tyrime nevertinamas atsinaujinančios energijos išteklių panaudojimas, kuris gali itin padidinti pastato energinį naudingumą. Reikšminiai žodžiai: administracinis pastatas; klimatas; energinis efektyvumas; atitvaros; stiklinis fasadas; apsauga nuo saulės.

The use of solar shading in future low energy office buildings is essential for minimizing energy consumption for building services, while maintaining thermal conditions. Implementing solar shading technologies in energy calculations and thermal building simulation programs is essential in order to demonstrate the effect of adaptive solar shading. In order to document the benefits of the shading technology, the description of the shading device in the thermal building simulation software must be described at a reasonably accurate level, related to the specific solar shading device. This research presents different approaches for modeling solar shading devices, demonstrating the level of accuracy in relation to measurement conducted in a full-scale façade test facility at Aalborg University. The research bridges the gap between increased complexity of solar shading technologies and the use of these technologies in thermal building simulation software. [ABSTRACT FROM AUTHOR]

This study presents an original method for improving the energy performance of buildings with glazed façades. For the proposed paper we analyzed using Ansys CFD software a study case for an office building with integrated heat pipes into the glazed façades. For the complete analysis of our proposed system we realized a financial study using the RETScreen 4 Software Suite. [ABSTRACT FROM AUTHOR]

This study presents a CFD Heat Transfer Analysis for Heat Pipes integration into Buildings with Glazed Façades. This consists into the introduction of heat pipes in the building envelope structure for taking over the heat from glazed façade cavity and transmission, respectively accumulating in the wall structure for achieving the indoor comfort parameters in winter and transitional seasons (autumn and springtime). [ABSTRACT FROM AUTHOR]

This work deals with daylighting for indoor quality atmospheres, considering building skins and side-views. We also tested the vision perception provided by highly glazed façades. Several Spanish restaurantswere analyzed, and twowere assessed andmeasured under outsidemidday high luminance. The selected pictures can be identified as restaurants via MIT Scene Recognition software and are used to demonstrate working, stressful, and socializing atmospheres. Light and vision detailed analysis was performed defining three workplanes-"table", "person", and "outside"-from the viewpoint of the user. The obtained DGP (daylight glare probability) for the first case (facing southeast) shows a higher glare probability than the second (facing north). In both restaurants, there is notable spatial contrast and high information content. If, in the overall perception, the adaptation from the intermediate workplane is considered, the DGP is lower than if only one workplane is considered. The conducted indicative survey shows that there is a high light contrast, and there are some undesirable visual elements. The studied fully glazed façades tend to provide fraught atmospheres. These would be useful for some stimulating activities; however, for calm restaurants that offer tasting menus with quality food, it seems that the studied fully glazed façades may not be suitable. [ABSTRACT FROM AUTHOR]

Double skin glazed facades (DGF) are an actual worldwide trend in new and refurbished buildings, even in warm climates with high solar radiation levels as in the Middle East and in Mediterranean climates. In such climates, overheating of indoor spaces and therefore excessive energy consumption are the main problems to be faced. These issues are commonly addressed mostly by thermal simulation or experimental evaluations on small prototypes. However, measurements on real-scale buildings with DGFs are very unusual. This information is crucial to understand and validate the predictions of the thermal behavior of the DGF technology. In this paper, thermal measurements were carried out in an unoccupied office building with a West DGF placed in the Northwest region of Argentina during 3 months in spring/summer. The air temperature exceeded in 10 °C the outdoor air and that indoor temperatures have not exceeded the outdoor levels in the hottest hours. Two correct design decisions were the use of low-e double hermetic glazing and the addition of a screenpainting to the external DGF panel. The experimental data showed that well-designed DGFs can reduce the summer energy consumption of buildings, even using West DGFs, in sunny climates. [ABSTRACT FROM AUTHOR]

This work deals with daylighting for indoor quality atmospheres, considering building skins and side-views. We also tested the vision perception provided by highly glazed façades. Several Spanish restaurants were analyzed, and two were assessed and measured under outside midday high luminance. The selected pictures can be identified as restaurants via MIT Scene Recognition software and are used to demonstrate working, stressful, and socializing atmospheres. Light and vision detailed analysis was performed defining three workplanes—“table”, “person”, and “outside”—from the viewpoint of the user. The obtained DGP (daylight glare probability) for the first case (facing southeast) shows a higher glare probability than the second (facing north). In both restaurants, there is notable spatial contrast and high information content. If, in the overall perception, the adaptation from the intermediate workplane is considered, the DGP is lower than if only one workplane is considered. The conducted indicative survey shows that there is a high light contrast, and there are some undesirable visual elements. The studied fully glazed façades tend to provide fraught atmospheres. These would be useful for some stimulating activities; however, for calm restaurants that offer tasting menus with quality food, it seems that the studied fully glazed façades may not be suitable.

[Display omitted] • PVGIS databases have been benchmarked against measured horizontal irradiances data. • Performance of the transposition models (horizontal to vertical) has been assessed. • Clear sky models transposed with anisotropic model are proposed as an alternative. • A filtration method for identifying the clear sky days has been proposed. • Impact of using various irradiance sources on glazing system performance is analyzed. The present study aims to benchmark the models utilized for estimating the solar irradiance on vertical planes that can facilitate the determination of critical conditions, which are utilized in the glazed facade design. Accordingly, in the first part of the study, the performance of PVGIS databases for Europe for estimating the solar irradiance components on the horizontal surfaces is compared with the on-site measurements at Bolzano airport (Italy). It is demonstrated that PVGIS-SARAH estimates both the global and diffuse solar irradiance components, compared to on-site measurements, with an acceptable error range (± 2–5%). The accuracy of isotropic and anisotropic transposition models is then compared for the same location, which demonstrates that the isotropic model tends to underestimate the global vertical incident irradiance by 6–12% of the daily peak value, while an agreement between the estimations of the anisotropic Perez model and the measurements is observed. Next, the performance of Ineichen, Solis and SPECMAGIC clear sky models, transposed with anisotropic Perez model, have been assessed utilizing field measurements on vertical facades at four different locations in Europe. The broadband version of Solis clear sky model, transposed with anisotropic Perez model, demonstrates R 2 scores between 0.85 to 0.95 for the considered locations, indicating that this approach can be utilized as an alternative to open-source/commercially available data sources to estimate the solar irradiance on vertical facades. Finally, for the case study of a triple glazing system, comparing the surface temperatures obtained employing the latter approach with those determined using other commonly utilized irradiance data sources shows a discrepancy of up to 7 °C. [ABSTRACT FROM AUTHOR]

Façade systems play an important role in fire compartmentation of a building and reducing the likelihood of fire spreading through and outside of the building walls. The use of sprinklers in building regulations often allows for smaller building separation. However, no additional benefits are usually given to additional internal sprinkler protection of the external glass façade using standard pendant sprinklers. Four compartment fire experiments were performed with non-fire-rated aluminium façades with two- and three-layered Insulating Glass Units (IGU), protected by pendant-type sprinklers (DN15, K-factor = 80, T = 68 °C). Sprinklers were in row 14–55 cm from the glazing, with 1.514–1.83 m separation distance. In all experiments, façades achieved satisfactory performance in terms of glazing integrity, insulation and reducing the thermal radiation. Under a non-uniform water distribution, parts of the glass were dry (1.7%–15.7% of IGU area), where we have observed soot deposition and local damage to fire exposed glass layer, but no loss of the structural integrity. The temperatures on the unexposed side did not exceed 86 °C, the peak measured temperature of the internal glass surface was 173 °C. The performed experiments confirmed the capability of standard pendant-type sprinklers to enhance the fire protection features of a building façade. Image 1 • Four large scale compartment fire experiments were performed. • Sprinklers may substantially improve the fire performance of building façade. • Non-uniform heat transfer through glass did not lead to loss of structural integrity. • Sprinklers efficiently cool the thermal plume from ventilation windows. • External thermal radiation from fire is shut out by the sprinklers. [ABSTRACT FROM AUTHOR]

The design of blast-resistant glazed façades can be required by building standards. The high-pressure generated by the blast wave air-front can lead to catastrophic failure of the glass panes and/or their load-bearing structure, with possible projection of fragments that constitutes a potential threat for human lives and properties. The time-dependent deformations-history is usually assessed via numerical analyses and/or experimental investigations, but it is difficult to recognize the role of each element in the complex dynamic response. As a guide to structural design, we here propose a simple analytical model that permits a synthetic but comprehensive view of the phenomenon. The dynamic interaction among the blast wave, the ensemble of glazed panels and load-bearing structure is studied in paradigmatic lumped-element models, representing glass panels supported by tensioned cables, using Rayleigh's method to reduce the response of each glass panel to a non-linear single degree-of-freedom oscillator. The dynamic equations are solved under blast pressure modeled via the Friedlander's waveform. This analytical treatment quantifies the importance of the load-bearing structure in absorbing energy from the blast wave. • An analytical model is used for a parametric analysis of cable-supported façades under blast waves. • Non-linear membrane effects in the glass panel are taken into account through Rayleigh's method. • Large deformations of the cable, with possibly a spring in series, are considered. • The dynamic equations are solved under blast pressure, modeled via the Friedlander's waveform. • A cable structure can adsorb most of the energy from the blast wave and preserve the glass panels. [ABSTRACT FROM AUTHOR]