Buildings — Open Access Journal

The World Green Building Council (WGBC) advocates improvements in employee health, wellbeing, and productivity in buildings as people are about 90% of an organisation’s expense and well exceed building costs and energy costs. It was reported that earlier research on workplace design primarily focused on physical arrangement of employees’ immediate work area, and ambient environmental qualities of the work area. Building organisation, exterior amenities, and site-planning have been given less attention. Therefore, we examine more closely the health relevance of both proximal and remote aspects of workplace design. Occupational stress is a complex phenomenon that is dynamic and evolving over time. This investigation reviews the existing fundamental conceptual models of occupational stress, workplace design, and connection to nature. It aims to develop an improved model relevant to work place design and occupational stress linked with connection to nature. The proposed improved model is presented with an appropriate causal loop diagram to assist in visualizing how different variables in a system are interrelated. The developed model highlights how connection to nature in workspaces can function as a work resource with a dual effect of improving physical wellbeing and psychological wellbeing. Full article

The development of environmentally-friendly methods as alternatives to chemical fumigation for controlling insect pests has attracted public attention. Among these methods, heat treatment is based on the use of fan heaters that are positioned by operators who typically establish their number and position within buildings to be treated. The aim of this research was to improve heat treatment effectiveness by applying a validated computational fluid dynamics (CFD) model for planning fan heater positions within the building environment. Based on a CFD model, which was built and validated according to experimental data acquired during heat treatment of a flour mill, simulations were carried out by changing the position and/or rotation of fan heaters with the aim of enhancing temperature distribution inside the building. The results showed that in some simulations the percentage of internal wall surfaces having a temperature value lower than that required for heat treatment efficacy was considerably reduced, by up to 56.7%. Therefore, the CFD approach proposed in this study could be used as a decision support system for improving heat treatment efficacy. Full article

This paper presents the full-scale experimental assessment of a log-house timber wall with partial thermal insulation under in-plane compression and exposed to fire on one side. A key aspect of the current design application for log-house systems is represented by geometrical details, like cross-sectional properties of logs (typically characterised by high depth-to-width ratios) and outriggers. The latter provides restraint condition for the examined walls and hence markedly affects their overall load-carrying capacity. As a result, careful consideration should be given to the choice of these details, compared to fully monolithic timber walls (i.e., made from cross-laminated timber), due to the possible occurrence of local structural and/or thermo-mechanical mechanisms. This is the case of exceptional loading conditions like fire load, as the fire resistance of these systems could be affected by a multitude of variables, including the presence (even though limited to few surfaces only) of thermal insulation panels. To this aim, the results of a full-scale furnace test are discussed in the paper for a log-wall with partial thermal insulation, namely thermal insulation applied on the outriggers only, under the effects of EN/ISO standard fire conditions. The results of Finite Element (FE) numerical studies are also reported, to further explore the load-carrying performance of the reference log-house specimen and compare it with the experimental observations. Several thermal insulation configurations are finally numerically investigated, showing their effects on the overall fire resistance of the assembly. In accordance with literature, the test shows that the log house’s timber wall is suitable to obtain a fire resistance of about 60 min under relevant loading. The FE results are in rather close agreement with the temperature measurements within the section of logs, as well as a qualitative correlation with respect to the mechanical behaviour observed in the full-scale furnace experiment. The key role of outriggers and their thermo-mechanical boundaries, finally, is emphasised. Full article

The priorities in the design of more sustainable buildings are quite dependent on the specific social context. In developing countries, the sustainability concept and priorities in the residential buildings sector are quite different from the ones of the developed countries, since there are still basic needs to answer. Therefore, this research is aimed at contributing to a better understanding of the concept of social sustainability in the residential building sector of the developing countries. A methodology to define and prioritise the social sustainability indicators is proposed and applied in the context of Palestine. The presented methodology is based on the sustainability indicators of international standards, on the most well know building sustainability assessment methods and in the analysis of their application to a specific context. It includes a methodology to prioritise the list of social indicators, by considering the expectations of two groups of building stakeholders: designers and building users. At the end, this research proposes a framework of social aspects to consider in the design of more sustainable residential buildings in West Bank, Palestine that is composed of twenty-one indicators, distributed among six sustainability categories and ranked according to their weight in the overall of sustainability level. Full article

Life cycle assessment (LCA) is the standard method for the quantification of environmental impacts within the construction sector, relying on available generic LCA databases. New developments, such as the increased influence of the building construction for LCA and the forthcoming of building information modeling (BIM), implicate new requirements on multiscale levels of development and complexity for LCA construction databases. At the example of the German “Ökobau.dat”, one of the leading LCA construction databases, this publication discusses whether the database is able to meet these requirements. The analysis shows the strengths of the Ökobau.dat with regard to standardization conformity (EN 15804, ILCD), data provision in machine-readable XML format, and the provision of an application programming interface. Shortcomings include incorrect linking of building life cycle inventory data with environmental information, incorrect documentation of functional units, missing generic datasets, the modeling of energy use data or the lack of a uniform structuring, or material classification. The authors propose solutions such as the provision of appropriate functional units, the implementation of a top-down approach to investigate the completeness of data based on existing nomenclatures or the extension with an appropriate material classification. This would allow for future viability and adaptability of Ökobau.dat for digital LCA. Full article

The performance of base-isolated steel structures having special moment frames is assessed. The archetypes, which are designed per ASCE/SEI 7–2016, are simulated in the Finite Element (FE) computational platform, OpenSees. Adopting nonlinear dynamic analyses using far-field ground motions, the performance of Drift-Sensitive Structural Components (DS-SC), and Drift-/Acceleration-Sensitive Non-Structural Components (DS/AS NSC) at slight, moderate, extensive, and collapse damage states are investigated. The effects of structural height, effective transformed period (T_eff), response modification coefficient (R_I), and isolation type on the performance of 26 archetypes mounted on Lead Rubber Bearings (LRBs) and Triple Concave Friction Pendulums (TCFPs) are evaluated. Computing 50-year probability of exceedance using the fragility curves and seismic hazard curves of the site, increasing T_eff reduces the role of R_I in the structural performance; variations in the height, as well as R_I, do not affect the risk of damages to the AS-NSC; the risk of collapse is not sensitive to the variations of T_eff. The TCFP systems represent superior performance than LRB systems in lower intensities. For longer periods and taller structures, the isolation type has less effect on the performance of NSC. Finally, the archetypes have less than 1% risk of collapse in 50 years; nevertheless, high-rise structures with R_I = 2.0 have more than 10% probability of collapse given the maximum earthquake. Full article

Much of the anticipated future growth in North America will occur in suburbia. The critical challenge that we will face is how to accommodate this growth in a sustainable and resilient manner. While the past 50 years have been characterized by suburban sprawl and low-rise development, “suburban sustainability” is increasingly making its way into the planning and urban design policy realm. This research investigates the spatial patterns of tall buildings in 24 suburban communities of three different regions including, Washington, D.C., Miami, and Chicago. The study identifies 10 different spatial patterns that prevail in suburbia and provides a concise summary of these patterns and reflects on their spatial and urban design aspects. The research concludes that the Tall Buildings and Transit-Oriented-Development (TB-TOD) model, an urban design approach that refers to vertical mixed-use clusters centered on mass-transit nodes, is one of the sustainable options for large regions going forward. The paper also discusses the challenges to the TB-TOD model implementation, mainly limited transit lines and community resistance. It ends by offering directions for future research. Full article

A considerable amount of energy is being consumed for heating and cooling indoor environments in order to provide thermal comfort. For older buildings located in the southern parts of Iran, particularly in Bushehr, many climatic and passive design strategies are being used to provide indoor thermal comfort. This architecture and these elements have been developed in response to unfavorable weather conditions. The current study aimed to identify those passive elements and evaluate indoor thermal comfort in older houses. To achieve these objectives, passive elements in main houses located in the ancient urban structure were first identified. Then, a house in the coastal belt, Tabib’s house, and another house inside the ancient urban structure, Nozari’s house, were selected for the purpose of field measurement. The results revealed that the passive techniques used in these older houses significantly provide sufficient indoor thermal conditions. The mean measured predicted mean vote (PMV) of Tabib’s rooms was 0.88 and the mean measured PMV of Nozari’s rooms was 0.91, which were in an acceptable range. The measured predicted percentage of dissatisfied of rooms in both houses were lower than 10%. The main factor in creating indoor thermal comfort in these houses was the natural ventilation and its availability in the selected houses. Full article

In this paper, a circular-economy framework is applied to the prefabricated building sector to explore the environmental advantages of prefabrication in terms of reduction, reusability, adaptability, and recyclability of its components. A qualitative approach is used to revisit the design, construction, and demolition stages of prefabricated buildings; in so doing, the circular-economy framework is applied to foster circular prefabricated modi operandi. Prefabrication of buildings can be divided into four entities: elements and components, panels (or non-volumetric elements), volumetric, and entire modules. Through an analysis of published research on how the circular economy can be applied to different industry sectors and production processes, seven strategies emerged, each of which revealed the potential of improving the circular economy of buildings. The first strategy is reduction of waste through a lean production chain. By reusing the waste, the second strategy investigates the use of by-products in the production of new components. The third strategy focuses on the reuse of replacement parts and components. The fourth strategy is based on design toward adaptability, respectively focusing on reusability of components and adapting components for a second use with a different purpose. Similarly, the fifth strategy considers the implications of designing for disassembly with Building Information Modeling so as to improve the end-of-life deconstruction phase. The sixth strategy focuses on design with attention to recyclability of used material. Finally, the seventh strategy considers the use of tracking technologies with embedded information on components’ geometric and mechanic characteristics as well as their location and life cycle to enable second use after deconstruction. It is demonstrated that prefabricated buildings are key to material savings, waste reduction, reuse of components, and various other forms of optimization for the construction sector. By adopting the identified strategies in prefabricated buildings, a circular economy could be implemented within the construction industry. Finally, seven guidelines were distilled from the review and linked to the identified strategies. Owing to their degree of adaptability and capacity of being disassembled, prefabricated buildings would allow waste reduction and facilitate a second life of components. Full article

Unreinforced load-bearing masonry (URM) buildings represent a significant portion of the non-engineered old buildings in many developing countries aiming to reduce the construction cost. The walls of those buildings are developed to resist gravity loads. Lateral loads induced by earthquakes or wind may cause severe their damage. In the current study, a numerical investigation is carried out for a seismic assessment of a typical four-story, load-bearing building in Giza, Egypt. The full 3D nonlinear dynamic analysis is carried out using the Applied Element Method (AEM), which proved to be efficient in such case where partial or total collapse is expected. The study includes two earthquake zones in Egypt called zone (3) and zone (5B), which are the actual studied building seismic zone and the highest seismic activity zone in Egypt, respectively. Carbon fiber reinforced polymers (CFRP) laminates with different thicknesses and different configurations are used in strengthening unreinforced masonry walls to study the efficiency of the proposed rehabilitation technique on a realistic structure. Full article

This paper aims to find the microclimate aspect within the building form and configuration of five low-cost apartments (henceforth rusun) in Bandung, Indonesia. There are parallel, square, and interspersed plots investigated with specific discussion on the microclimate aspects that gain human perception of outdoor thermal comfort. The microclimate prognostic model, i.e., ENVI-met, was used to determine the mean radiant temperature (Tmrt), which was then used to describe the living quality of outdoor thermal comfort, i.e., PET (physiologically equivalent temperature) in a hot-humid climate context. A parallel plot with building orientation toward north-south was found as the most beneficial building form and configuration. Somehow, the parallel plot toward the west-east orientation did not provide similar performance. Nevertheless, the square plot provided uncomfortable perception as there was an absence of building shade within the wide open space and ground cover to absorb the insolation. The interspersed plot can be considered for the building configuration because it generates more wind among other plots. The building form and configuration of rusun with passive design seems to not be able to achieve outdoor thermal comfort. The highest PET value of Model D with the square plot had PET = 41 °C (hot) while the lowest PET in Model A with the parallel plot (N-S) had PET = 34.2 °C (slightly warm). Full article

The aim of this project is to investigate the behaviour of several special types plasters specifically designed to degrade the most common pollutants which are present in the atmosphere. In particular, specific additives have been added to these plasters, in order to obtain a broad spectrum of active and synergic response, each of which have peculiar functions: - microporous materials, such as clinoptilolite, a natural zeolite, that promotes the adsorption of air pollutants thanks to its porous nature; - nano-fillers, such as carbon nanotubes, that behave both as reinforcing agents as well as adsorbent materials; - photochemical agents, such as titanium oxide, that degrade air pollutants, previously adsorbed on carbon nanotubes and zeolites, thanks to the action of light that activates photodegradation reactions. All the samples were also characterized in terms of mechanical properties, adhesion to supports and water absorption. Furthermore, photodegradation tests were carried out by exposing plaster surfaces, wetted with a Rodamine solution, to Ultraviolet rays (UV) for different times. Plasters photodegradative capacity was evaluated and the results highlighted the fact that the designed admixtures showed an important photodegradative action, strictly dependent on the types and specific ratios of the selected additives. Full article

Use of composite steel shear walls (CSSW) in earthquake-resistant structures has grown in recent years. However, no thorough information exists on their performance, especially in cases where openings are present. In the present study, in order to first validate the analysis method, ABAQUS was used to model the studied composite shear wall with gap at UC-Berkeley, according to the results of which, a good agreement between the experimental and analytical models was observed. Then, the effect of the position and number of the openings on the performance of the walls was addressed. To this end, models with various openings, including openings close to the beam/column, horizontal/vertical openings and distributing opening, were prepared and analyzed. The results indicate that the maximum reduction in stiffness and strength occurred in walls with single openings. The size of opening and the opening’s area significantly affect shear wall performance. Ultimately, artificial neural network and fitness function tools were employed to obtain predictive models for shear wall performance. A neural network has proven an appropriate alternative method for predicting the displacement, stress, and strength of the composite shear wall. Full article

Prefabricated forms of construction have led to the rapid onsite assembly of buildings however there are still on-site tasks and processes which can be reevaluated and redone specifically in keeping with the principles of prefabrication instead being adapted to fit its purpose. One such process is that of waterproofing between prefabricated panels and modules which come from the factory fully complete façade and all. Conventional means of waterproofing can be used however it results in more work done on site, potential delays and generally requires access from the external face of the building. This paper presents the Modelling, Implementation and Evaluation of purpose developed weatherproof seals specific for Prefabricated Construction. An overview is provided of the entire development process and specific focus is given to the modeling using finite element analysis (FEA) computer simulations, manufacturing and testing which then resulted in the implementation in a prefabricated panelised building which is used as a case study and the means of further evaluation. These strategies have enabled an efficient and robust prefabricated waterproofing solution specific for this form of construction to be understood and implemented. The resulting case study has successfully verified the time and cost savings when compared to conventional techniques whilst still providing a durable and effective weatherproof seal for prefabricated panelised and modular systems. Full article

A novel smart solar-powered light emitting diode (LED) outdoor lighting system is designed, built, and tested. A newly designed controller, that continuously monitors the energy status in the battery and, accordingly, controls the level of illumination of the LED light to satisfy the lighting requirements and/or to keep the light “on” the longest time possible, has been developed. The use of such a reliable solar energy-driven lighting system, with maximum time when the light is “on”, will eliminate the sudden-death of light problem present in conventional photovoltaic (PV) outdoor lights and, therefore, will enhance the natural surveillance and feeling of safety in sustainable buildings and cities. Furthermore, the new smart control eliminates the overdischarge of the system battery and, thus, ensures a longer lifetime of the system battery. Experimental measurements on a system using a 30 W LED light showed that the operating hours of the new system reached 29.16 h (1750 min), while the operating hours for a similar conventional system were 20.86 h (1252 min). Thus, the new lighting system was demonstrated, securing more than 40% of operating hours than the conventional systems. Full article

Daylight usage in buildings improves visual comfort and lowers the final energy demand for artificial lighting. The question that always occurs is how much conservation can be achieved? New or rare materials and constructions have a lack of information about their application. Therefore, the current investigation quantifies the daylight and energy performance of a rare multi-layer textile membrane roof. A translucent, thermal insulation with a glass fibre fleece between the two roof membranes combines daylight usage and heating demand reduction. A sports hall built in 2017 is used as a case study building with 2300 m² membrane roof surface. The optical properties of the roof construction were measured with a total visual light transmittance τ_v of 0.72% for a clean surface. A climate-based annual daylight modelling delivers daylight indicators for different construction scenarios. The results show that, in comparison to only one glass façade, the additional translucent and thermally insulated membrane roof construction increases the annual daylight autonomy (DA₇₀₀) from 0% to 1.5% and the continuous DA₇₀₀ from 15% to 38%. In the roof-covered areas of the sport field, this results in a 30% reduction of the electricity demand for artificial lighting from 19.7 kWh_el/m²/a to 13.8 kWh_el/m²/a, when a dimming control is used. The study also found that the influence of the soiling of one layer decreases its light transmittance by a factor 0.81. Two soiled layers lower τ_v by a factor of 0.66 to 0.47%. This increases the electricity demand for lighting by only 12%. The results should be very valuable as a comparison and benchmark for planners and future buildings of a similar type. Full article

Satisfactory weatherproofing of buildings is vital to maximise their design life and performance which requires the careful design of external sealing technologies. Systems commonly available have served well in conventional construction however with many prefabricated systems emerging in the building industry new and novel means of weatherproofing between panels and modules need to be developed purpose specific to this application. This paper presents a holistic and fundamental methodological approach to Design and Development of waterproof seals and has been applied specific for prefabricated panelised and modular systems. Two purpose specific weatherproof seals are finally presented. Flow charts of the overview of the suggested methodological approach and the processes within which include DfMA that have been incorporated into understanding and developing seals for this practical application. These strategies have enabled a resourceful and holistic set of processes that can be adapted and used for similar forms of product research in new and developing areas of construction such as prefabrication. The design and development process is thoroughly investigated and has resulted in an exploration of the technical challenges and potential solutions which take into consideration factors from installation limitations to building tolerances. Full article

The design of environmentally-friendly buildings relies on the work of interdisciplinary teams who have to look at problems in a holistic way. Teams need to communicate, collaborate, and make decisions not solely based on first cost considerations. For this purpose, Target Value Design (TVD) related practices are being used to deliver green buildings in Southern California while meeting strict code requirements and addressing the needs of multiple stakeholders in a collaborative fashion. This study did not quantify costs associated with design and construction of sustainable buildings. It used an analytical process that compared and contrasted available literature on TVD and interviews with industry practitioners to investigate the use of TVD-inspired practices in the construction industry in Southern California and identify the current use of TVD-inspired practices in the design of green buildings. The study revealed that, even though practitioners might not be aware of how TVD can be fully implemented in these projects, a number of TVD-inspired practices are currently being used. Examples are provided to illustrate their practical use in the design of sustainable buildings and how practice compares to theory regarding TVD implementation. Full article

Waste generation from agricultural and construction industries is growing at an upsetting rate that causes a heavy burden on landfill facilities. On the other hand, the construction industry is exhausting natural resources thereby posing environmental problems. This study investigates the potential use of agro-industrial waste such as rice husk ash (RHA) and construction waste like reclaimed asphalt pavement (RAP) as promising construction materials. The durability and physical and mechanical properties of concrete were assessed by partially replacing cement and virgin aggregates with RHA and RAP, up to 20% and 50%, respectively. A total of 22 mixes were studied, twelve of which were devoted to studying the collective effects of RHA and RAP on the engineering properties of concrete. Based on experimental results, RHA and RAP decreased slump, compacting factor, density, water absorption and sorptivity. RHA increased compressive and tensile splitting strength, whereas RAP decreased compressive and tensile splitting strength. Comparable strength and favorable sorptivity values were obtained when 15% RHA was combined with up to 20% RAP in the concrete mix. Thus, utilizing RHA and RAP as concrete ingredients can contribute to solid waste management, engineering and economic benefits. Full article