Figure 3 - uploaded by Ryan Danks
Content may be subject to copyright.
A sun path diagram for Los Angeles with solar elevations below 30° outlined.  

A sun path diagram for Los Angeles with solar elevations below 30° outlined.  

Source publication
Conference Paper
Full-text available
Solar reflections are a fact-of-life for many who live in cities. However, modern architecture with high window-to-wall ratios and curved, organic forms can lead to building facades that reflect sunlight in unanticipated ways. Reflective facades have the potential to both scatter and concentrate solar reflections; at a minimum, this can be a nuisan...

Context in source publication

Context 1
... it is important to note that the thermal impacts of reflections during midday periods are more of a concern due to the greater intensity of solar insolation at these times.) As an example, Figure 3 is a sun path diagram for Los Angeles, note how the sun will cover over 225° of azimuth during a summer day, exposing not just the southern facades but potentially the entire building envelope to direct sunlight and potentially cause glare. Also notable is that low solar inclination angles (say below 30°, which is outlined in black) can occur from ENE to SSE and from SSW to WNW depending on the time of year. ...

Similar publications

Article
Full-text available
The current trends in modern architecture are focused on minimising the boundaries between the external environment and interior of the building. This requires a continuous increase of the amount of translucent surfaces allowing natural sunlight to enter the building, not only in facades but also through interior structural elements. The research p...

Citations

... It is therefore important to provide the designers with a clear overview of the problem and its intensity in a way that prevents general errors during the early design stages and guides a detailed analysis that will reduce the risk of future local environmental problems that can lead to extra costs after the construction [45]. Therefore, the objectives of this research are to: ...
... In order to assess the increment of solar radiation generated by tall building solar reflection, three skyscraper scale models were built based on a review of contemporary skyscraper dimensions and shapes [35,41,45,48]. ...
Full-text available
Article
Urban climates are highly influenced by the ability of built surfaces to reflect solar radiation, and the use of high-albedo materials has been widely investigated as an effective option to mitigate urban overheating. While diffusely solar reflective walls have attracted concerns in the architectural and thermal comfort community, the potential of concave and polished surfaces, such as glass and metal panels, to cause extreme glare and localized thermal stress has been underinvestigated. Furthermore, there is the need for a systematic comparison of the solar concentration at the pedestrian level in front of tall buildings. Herein, we show the findings of an experimental campaign measuring the magnitude of the sunlight reflected by scale models reproducing archetypical tall buildings. Three 1:100 scaled prototypes with different shapes (classic vertical façade, 10% tilted façade, curved concave façade) and different finishing materials (representative of extremes in reflectance properties of building materials) were assessed. A specular surface was assumed as representative of a glazed façade under high-incidence solar angles, while selected light-diffusing materials were considered sufficient proxies for plaster finishing. With a diffusely reflective façade, the incident radiation at the pedestrian level in front of the building did not increase by more than 30% for any geometry. However, with a specular reflective (i.e., mirror-like) flat façade, the incident radiation at the pedestrian level increased by more than 100% and even by more than 300% with curved solar-concentrating geometries. In addition, a tool for the preliminary evaluation of the solar reflectance risk potential of a generic complex building shape is developed and presented. Our findings demonstrate that the solar concentration risk due to mirror-like surfaces in the built environment should be a primary concern in design and urban microclimatology.
... Reflection of light from high-rise façades is a commonplace occurrence in modern cities, in particular with the use of large glass façade systems to improve energy efficiency in buildings. What can be seen as little more than a nuisance, does have the potential to create more dire risks due to the confluence of highly reflective material and non-linear façade designs (Danks et al., 2016b). Examples include the Disney Concert Hall in LA which has a highly reflective metal façade which ultimately needed to be partially roughened to reduce reflection (Schiler and Kensek, 2009), the Vdara Hotel and Spa in Los Angeles where the glass façade made the pool area too hot for guest to comfortably be able to use (MSNBC.com, ...
Full-text available
Preprint
This work presents a comprehensive review of how the landscape of fire safety challenges of ‘green’ attributes of buildings has developed since 2012. It is based on a global information search into: fire events involving ‘green’ and/or sustainable building materials, systems and features; emerging ‘green’ building materials, systems and features; and research, regulatory changes, engineering approaches, risk mitigation strategies, and firefighting tactics associated with fire challenges with ‘green’ and/or sustainable building materials, systems and features. While the research is comprehensive is scope, it is not exhaustive in detail, given the extent of advancement in these areas which has occurred since 2012. And, while significant advancements have been made, gaps remain, and strategies for proactively incorporating fire performance into development of new ‘green’ building materials, systems and features (product development) are lacking, the tools to proactively assess the fire performance of ‘green’ building materials, systems and features at the product level (e.g., fire performance testing), and as installed in buildings, are lacking, and a broader building regulatory framework and design philosophy for achieving sustainable and fire resilient (SAFR) buildings is also lacking. Based on the overview conducted and the analysis undertaken, a set of recommendations for future work to address gaps and to advance the concept of SAFR buildings and communities have been identified.
... It often causes thermal and visual discomfort simultaneously. Several studies and reports have addressed the potential danger of reflected sunlight from highly reflective and specular building facades Schiler 2007, 2012;Schiler 2009;Duell and Webb 2013;Mayerowitz 2010;Danks, Good, and Sinclair 2016). 20 Fenchurch Street in London has a concave specular facade that reflects and concentrates strong sunlight onto the ground and neighbouring buildings ( Duell and Webb 2013;Wainwright 2013). ...
... In a city, there is the possibility that one will experience multiple or intensified glare effects, especially with unique building facade geometries such as concave, convex or saw-tooth shapes. Concave facade geometries with specular materials can focus sunlight reflection into one point, and the focused sunlight reflection can seriously damage human vision or increase the surrounding temperature beyond acceptable levels (Danks, Good, and Sinclair 2016). Convex or saw-tooth-shaped building facades do not focus or intensify but can spread sunlight reflections in larger areas so that neighbours can be affected by reflected sunlight for a long period of time. ...
... It is difficult to prove whether reflected sunlight can seriously deteriorate human comfort in neighbouring buildings or public outdoor spaces. Yet, it is acknowledged that building facades have huge impacts on occupants' visual and thermal comfort, so it is not difficult to imagine that they would also cause huge impacts on human comfort for those who are outside a building ( Schiler and Associates 2004;Schiler and Valmont 2005;Schiler 2007, 2012;Kensek 2007, 2013;Schiler 2009;Danks, Good, and Sinclair 2016). Therefore, it is necessary to develop a validated evaluation methodology to quantify levels of the impact on human comfort. ...
Article
Highly reflective and specular building envelopes have become widely adopted not only for aesthetic reasons, but also to increase building energy savings and improve occupant comfort. However, they can also make significant and sometimes unintended impact outside the building envelope. Reflected sunlight from highly specular building envelopes can cause discomfort glare to people outside buildings. A human subject study was performed in an outdoor research setting. High dynamic range imaging was used to capture exterior glare scenes and to visualize glare sources in the field of view. Collected subjective evaluation data and captured glare scenes were statistically analysed to prove the existence of exterior glare problems. Perceptible and disturbing glare levels were experienced by the participants, and strong correlations were found between visual discomfort and excessive sunlight reflections from specular building envelopes. Exterior glare scenes were also documented in downtown Los Angeles to explore existing problems.
Book
In the last few decades, building design has been shifting toward more energy-efficient and better-performing buildings. Although the main focus is usually on the reduction of energy use for the operation and construction of buildings, the awareness regarding the benefits of higher occupant comfort and health has shifted the focus toward a more holistic treatment of building design. The exposed notion was further emphasized during the last two and a half years. Firstly, the COVID-19 pandemic and the realization that the indoor environment is directly related to occupants' health, and secondly, the energy insecurity fulled by the Ukrainian war. Therefore, we have to realize that contemporary high-performance buildings will not only have to be energy efficient but will also have to address synergetic interconnectedness between indoor environment, user health and comfort while at the same time being sustainable and resilient. A task that is not easily achieved and is further complicated by the issues of the present anthropogenically induced global warming that necessitates adaptation of buildings to the future climate already during the design phase. With the exposed complexity and interconnectedness of parameters influencing the design of high-performance buildings, a crucial research question emerges – "how to accomplish appropriate optimization among opposing and contrasting demands of different fields governing the design of high-performance buildings?" This question, of course, is not answered in the present reprint book of a Special Issue of the Sustainability journal. Nevertheless, papers published in it represent essential contributions that broaden the knowledge in the field of architectural engineering and, as such, provide a small but valuable contribution to creating a sustainable and resilient built environment. The content of the Special Issue and the present reprint book can be roughly divided into two parts. The first one includes papers primarily concerned with the functioning of the building and its components concerning energy use. In contrast, the second part addresses the occupant's comfort concerning the building. The book's first part consists of chapters 1 to 5 and covers some interesting aspects related to building design. Chapter 1 deals with building envelope optimization, and integration of passive cooling measures in buildings design by adopting a building simulation approach. Chapter 2 highlights the risks associated with buildings designed with the bioclimatic approach in the context of uncertain future climates. This chapter especially talks about the overheating problem in central Europe's residential buildings. Chapter 3 mentions retrofitting buildings with phage change materials and aerogel to adapt the building to extreme heatwave conditions. It also reports that using the above materials significantly reduces energy use, peak cooling load, CO2 emissions and operational energy cost for a typical Australian house in the Melbourne climate. Chapter 4 highlights the impact of the building shape factor on energy demand and CO2 emission in the cold Oceanic climate of southern Chile. Through case studies, the authors concluded that a shape factor below 0.767 leads to a decrease in energy demand under the studied climate. Chapter 5 addresses the issue of the urban heat island effect (UHI) and associated energy consumption in buildings. Through the paper, the authors conducted a systematic literature review of white roofing materials in emerging economies in the context of parameters such as energy performance cost-benefit, maintenance and consumer indifference. The second part of the book consists of chapters 6 to chapter 9. An adaptive thermal comfort study in university hostel dormitories is presented in chapter 6 of the book. This chapter put forth the characteristics of the subject's seasonal thermal perception and adaptive actions to restore comfort in the hostel dormitories of the composite climate of India. Chapter 7 reflects the impact of the high albedo materials used in the tall buildings on pedestrian streets in an urban environment. Authors in their study found that diffusely reflective façades did not increase the incident radiation at the pedestrian level by more than 30%. However, in the case of a specular reflective façade, the situation worsened due to an increase in incident radiation by 100% to 300% and should therefore be avoided. A student spends a considerable amount of time in education buildings during her or his education, starting from kindergarten to the university level. It is also evident from the published research that adequate thermal comfort impacts students' learning curve. Chapter 8 of the book highlights the recent advancement in thermal comfort in educational buildings and the associated issues. Lastly, Chapter 9, through the literature review, addresses the parameters that affect thermal comfort and the instruments used in field surveys to record thermal comfort parameters. This chapter emphasized understanding occupant's behaviour and individualized approaches. Ultimately, we must acknowledge that the Special Issue and this reprint book would not exist without the authors' contributions. Therefore, we thank everyone for their valuable and interesting contributions that will undoubtedly increase our knowledge in the field of high-performing buildings. Of course, the Special Issue would never have come about without the opportunity to edit it given to us by the MDPI and the editorial board of the Sustainability journal, for which we are grateful. Lastly, we would like to extend appreciation for support to our families, loved ones and our current and past colleagues that have all in some way contributed to the creation of the reprint book and Special Issue.