Energy Efficient Facade Research Articles

Thermal properties of new ceramic biomaterial for building façades

The selection of materials for a building facade is based on the dimensions of sustainability: environmental, economic and social dimensions, which form the basis of design and construction in terms of environmental conservation and energy efficiency. Furthermore, this implies the formula for maintaining balance: comfort in the indoor environment, care for nature, minimal economic expenses. This paper focuses on the investigation of a new material composed of bio and recyclable materials: clay, sawdust, and slag, i.e. materials found in abundance in nature as well as materials left out of use. The selected materials offer significant potential for use in construction industry, for building façades. Laboratory testing of the thermal properties of the new material, particularly of the thermal conductivity λ (W/m·K) that is crucial for thermal comfort in buildings to promote energy efficiency, has been performed. Three sets of samples (9 samples in total) with different proportions of the constitutive materials were tested using the Heat Flow Meter (HFM) instrument. Based on the results obtained, several conclusions have been drawn to demonstrate the potential for interaction among used materials, offering advancements in terms of thermal properties. Namely, thermal conductivity of the tested samples varies between 0.14 W/m·K and 0.18 W/m·K, depending on the density of the samples. This value is 7-9 times lower than the thermal conductivity value of traditional clay full bricks without voids and cavities and indicates new possibilities for energy efficient facades, promising environmental preservation, harmonization with nature, offering the solution with the slag and sawdust deposition.

Integrating resilience in the multi-hazard sustainable design of buildings

Recent natural disasters and climate change-induced extremes emphasize the urgent need to enhance the overall resilience of society by addressing the various hazards that buildings may face. Current design approaches recognize the need for integrated risk assessments, but studies primarily focus on existing buildings and single hazards, neglecting the impact of multiple hazards and resilience quantifications. However, it is crucial to consider multi-hazard scenarios and quantify economic, environmental, and resilience losses to pursue effective solutions from the early-stage design of both new buildings and retrofitting interventions. This paper presents a practical multi-criteria approach to support design decisions for enhanced safety, sustainability, and resilience of buildings against earthquakes and heatwaves. The proposed approach is applied to a commercial building with various seismic-resistant and energy-efficient facades. Non-linear seismic assessments are conducted to predict the potential impact concerning repair costs, carbon emissions, and the resilience loss at the design-level earthquake. Additionally, a whole life-cycle analysis and dynamic energy simulations are performed to calculate the financial and carbon losses resulting from power consumption and the ability of the building to maintain energy efficiency under extreme heat. Finally, the study employs a multi-matrix decision-making approach based on integrated economic, environmental, and resilience losses to guide the design selection. The results demonstrate that earthquake-resistant facades can significantly reduce financial losses by over 50%, with seismic resilience playing a crucial role in the final decision. This approach facilitates more effective investment decisions for building projects, enabling the quantification of the effectiveness of integrated strategies in reducing overall potential losses.

Performance-based Generative Shape Grammar Method: Energy Efficient Facade Design for Fully Glazed Multi-Storied Office Building - Hot and Humid Climate, Chennai, India

The traditional building form design or form-making is an intuitive design method that is neither efficient nor competent for energy-efficient façade design. The form-making design approach threatens sustainable development in India. This paper discusses the new tread of form-finding, a process in which the framework is set for parameters to interact. It suggests a performance-based shape grammar (PBSG) generative design method for façade finding and evaluates it as an energy-efficient facade design method for FGM office buildings for India's hot and humid climate.A research method to develop PBSG rules for a given project framework was demonstrated by redesigning a case sample site and evaluating the existing FGM office building in the sample site. The PBSG methods in two stages apply multiple rules, first for form-finding and later for façade plane-finding for energy efficiency.It was observed that the SG resultant generated form was 42% more energy-efficient than the existing design using the same envelope materials, HVAC equipment, development regulations, and context.The outcome of this study provides a framework for a generative design process using PBSG in the early design stages and proves to be an energy-efficient design method for India's hot and humid climate.

Development of new tool joint for modular systems made of cellular polycarbonate

The paper discusses the use of solid and structural polycarbonate modular systems in energy efficient facades and roofs of unique modern buildings. Inferior to nearly all translucent materials by light transmission, cellular polycarbonate sheets offer a combination of important consumer properties, such as impact resistance, light weight, flexibility and chemical stability. At the current stage of construction development featuring cellular polycarbonate modules, the assembly (installation) fails to meet the constructability and work safety requirements. To address these drawbacks of cellular polycarbonate structural modules, a new butt joint is suggested consisting of two separate C and T shaped profiles, where one joint profile is placed inside the other one’s cavity after their fastening to a cellular polycarbonate sheet. To build a variety of most complex curved enclosures, the coupling parts can be rounded similar to existing ready-to-use cellular polycarbonate sheets with U-joints. The paper outlines the installation of cellular polycarbonate modules with the new joint profiles. To improve the constructability of vertical translucent enclosures, modular systems can be enlarged on special benches and installed using vacuum lifting beams. The reliability and safety of the new structures is ensured by extensive profile resting upon metal or other load bearing supports.

Numerical study on the energy performance of building zones with transparent water storage envelopes

Researches on water wall passive solar technologies, especially the numerical study on the energy performance of building zones with Transparent Water Storage Envelopes (TWSEs), are reported in this paper. TWSE is a climatic adaptive building envelope consisting of visually transparent modular water containers, exterior shading devices, water supply and return pipes. It is an upgraded water wall that can serve both as an energy efficient facade and an auxiliary water cistern in a building. Currently the energy simulation involving transparent water walls cannot be explicitly done in all energy simulation programs because transparent envelopes are always predefined as the surfaces without thermal mass due to the embedded algorithms complied with ISO15099 standard. A numerical approach based on the integrated energy and computational fluid dynamics (IE&CFD) simulation was developed for solving the energy simulation problem related with TWSEs. A simplified optical model of TWSE was proposed and validated through light transmission testing. Meanwhile, cooling and heating loads of a zone with TWSEs and conventional glazing in summer and winter months were studied. The thermal performance of a TWSE relative to the conventional glazing was also investigated via the comparative thermal box testing. Based on the simulation and testing results, it reveals that TWSEs can exceed most high performance coated glazing with regard to solar radiation control, and they are also exceptional energy efficient transparent envelopes that can outperform the ASHRAE standard window and conventional glazing in terms of cooling and heating load reduction as long as being configured and operated properly according to their physical characteristics and outdoor climatic condition. Furthermore, the innovative technical paradigm of TWSEs, along with the numerical approach developed for their energy simulation, demonstrates a wide range of versatility to be implemented in research and practice for ultra low energy buildings.

Thermal bridging problems on advanced cladding systems and smart building facades

Double-skin facades (DSFs) are a technology that lies behind innovative energy efficient facade systems. While it provides a potential for high energy efficient buildings, other important parameters, like point thermal bridge problems, are in most cases overlooked. The aim of this study is to investigate the magnitude of this approach and the effect it might has on the overall heat flow estimation in buildings. The study performs a numerical analysis of heat flow through the points where such effects are found, in order to analyse their nature under different design parameters selection like the use of thermal breaks, the substrate wall material, the thermal insulation thickness and the type of anchors used to securely connect both facade skins. The results are then applied to a case-study office building aiming at quantifying the overall contribution of point thermal bridges to heat flows through the building envelope. As the analysis shows, point thermal bridges in well-insulated envelopes have a heat-loss similar to the one from 1 m2 of facade’s wall. The overall effect at DSFs can surpass 25% of total envelope heat flow, leading to a large underestimation of actual heat flows through the building envelope. Overlooking their contribution, as many European national energy efficiency regulations currently do for the shake of simplicity, has a significant effect in widening the gap between predicted and actual energy efficiency of buildings.

Influence of different pigments on the facade surface temperatures

More intensive shades of color are being used with external thermal insulation composite systems (ETICS) on energy-efficient facades. These surfaces heat up extremely and cause damage in ETICS. Based on an analysis of laboratory examinations and practical measurements (test houses) as well as on computations, this paper analyzes commonly used relative luminance (RL) and if this is of an adequate size for the prediction of the surface temperature. Significant issues are: (a) the deviation of the RL limit, (b) the performance capability and temperature advantages of improved pigmentation concepts (infrared reflecting pigments) on ETICS. Additionally, the total solar reflectance (TSR) and its influence on the surface temperature are evaluated.

Evaluation of the effect of smart facade systems in reducing dynamic response of structures subjected to seismic loads

To date the engineering community has seen facade systems as non-structural elements with high aesthetic value and a barrier between the outdoor and indoor environments. The role of facades in energy use in a building has also been recognized and the industry is also witnessing the emergence of many energy efficient facade systems. This paper will focus on using exterior skin of the double skin facade system as a dissipative movable element during earthquake excitation. The main aim of this study is to investigate the potential of the facade system to act as a damper system to reduce earthquake-induced vibration of the primary structure. Unlike traditional mass dampers, which are usually placed at the top level of structures, the movable/smart double skin facade systems are distributed throughout the entire height of building structures. The outer skin is moveable and can act as a multi tuned mass dampers (MTMDs) that move and dissipate energy during strong earthquake motions. In this paper, using a three dimensional 10-storey building structure as the example, it is shown that with optimal choice of materials for stiffness and damping of brackets connecting the two skins, a substantial portion of earthquake induced vibration energy can be dissipated which leads to avoiding expensive ductile seismic designs. It is shown that the engineering demand parameters (EDPs) for a low-rise building structures subjected to moderate to severe earthquakes can be substantially reduced by introduction of a smart designed double skin system.

Thermal Induced Climatic Loads of Insulated Glazed Units in Energy Efficient Facades

Climatic loads on Insulated Glazed Units (IGU) have been investigated since the early 1990s. Beginning in 1996 a German technical guideline defined the procedure to respect climatic loads in static design of IGUs. Furthermore the required values of climatic changes and thermal changes of Double Glazed Units (DGU) have been determined. In practice, those values have been applied to other systems like Triple Glazed Units (TGU) as well as Double Skin Facades (DSF). In the last two decade’s those values haven not changed. This paper presents the results of a study on IGU’s in summer conditions, evaluating the thermal performance recent constructions. The upgrade from DGU to TGU causes a significant change of the thermal behavior. By adding a third glass layer, the middle glass gets insulated on both sides. In case of solar radiation the middle glass layer absorbs energy and is disabled to release energy. As a result, higher temperatures can be reached on TGU. By considering ventilated or not ventilated DSF’s, external or internal shading devices can influence further changes in the thermal behavior. This paper shows the development of an iterative calculation model by including present European standards. The model is able to deal with factors mentioned above. The results of different facade studies are shown and compared to the DIN 18008 standard. Furthermore the ongoing changes through European prestandards were discussed. Over all the study shows that a more sophisticated approach is necessary to determine correct temperature and climatic loads.

MODELING AND OPTIMIZATION OF ORGANIZATIONAL AND TECHNOLOGICAL SOLUTIONS IN THE CONSTRUCTION OF ENERGY EFFICIENT FENCING STRUCTURES IN CIVIL ENGINEERING

The investigations of thermal and technical features of enveloping structures show that at the present time the structures of outer walls with hinged ventilated facades are the most energy efficient. The facades with air space are widely used both in residential and in public buildings. In the recent years the problems related to energy efficient enveloping structures are being actively investigated. The problems of modern Russian and foreign energy-efficient facade systems, their technical and structural solutions and the main methods of their installation are reviewed in the article. The methods of solving the tasks of research are proposed and the obtained results are described. The development of organizational and technological solutions for sealing of joints of front panels during installation of ventilated facades by pre-assembly method was the basis of the method of solving of the problem. The obtained data together with the developed structural and technological solutions may become the base for the development of technical rules and regulations.

Notes on the design process of a responsive sun-shading system: A case study of designer and user explorations supported by computational tools

AbstractResponding to growing concerns regarding energy-efficient facades, this paper describes the structure and process followed in the design of a responsive sun-shading system based on the use of rotating plates with two degrees of freedom. The proposal considers, among others, the definition of variable design parameters, areas of performance evaluation and control, and construction detailing development represented by a first 1:2 unit (module) model. In the process, computational simulation procedures were employed to explore configurational possibilities that would provide high-performance solutions to the light requirements of the particular covered spaces. In developing the system, it was noticed that due to the highly subjective requirements of users in terms of quantity and quality of lighting, a purely Boolean control system would not always be appropriate. Following from that, and taking advantage of the dynamic nature of the system, a further approach of control supported by fuzzy logic was also implemented at the operative state, whose logic is explained. Digital simulations were carried out to assess the performance of the system, and their results demonstrate more even light distribution levels compared to traditional systems.

Sound Insulation of Energy Efficient Facade Construction

Environmental noise affects a large number of people. It is estimated that 20% of the EU population, or around 80 million people live in conditions of unacceptable noise. Three key possibilities for community noise management are control at the source of noise, control at the path from source to receiver and protection at the place of reception. In all three cases, noise should be reduced to the lowest level achievable in the particular situation. This study deals with the problem of protection against community noise at the receiving site. The paper considers the energy efficient façade construction and how they contribute to the protection of noise in urban areas.

Towards Energy Efficient Facade Through Solar-powered Shading Device

In tropical regions (23.50N – 23.50 S), the east-west building facades receive the greatest amount of solar radiation for vertical walls. The need for glazing windows in that area sometimes cannot be avoided due to various reasons regarding to space planning inside the building. The presence of east-west glazing windows causes the increasing of air conditioning load of the building at a significant rate, which causes increasing energy usage. There are several external shading devices available to be used to limit the incoming low-altitude angle sunlight falling to that direction, however all the available sun shading devices are not adjusted and based on the fixed location as a part of building façade. Since the sun moves regularly according to its daily and seasonal path, generally the fixed external sun shading does not function well to reduce solar heat gain as well as to keep an indoor standard illumination level simultaneously.The solar-powered automatic vertical shading device is the solution for the problem since it obstructs the direct solar heat using the received solar energy itself, and at the same time maintaining the required daylight illumination at an appropriate level inside the room. The research dealing with solar-powered automatic shading device was developed through integrated interdisciplinary and collaborative approach at the Center for Building Energy Study Petra Christian University Surabaya.The broaden usage of this device also opens possibility toward a more specific culturally façade that encompasses functional needs, energy efficiency criteria, architectural aesthetic value, and cultural appearance of building.

Aerogel granulate glazing facades and their application potential from an energy saving perspective

Aerogel granulate glazing systems for energy efficient buildings have various promising properties, including their thermal insulation properties and translucent features. In this study, the energy performance of aerogel granulate glazing systems was evaluated by considering an office facade consisting of a translucent aerogel granulate glazing system at spandrels. The results indicate that such a glazing facade can achieve a lower energy demand than a double glazing facade in cooling dominated climates, such as Tokyo and Singapore. It is also possible to secure better energy savings owing to increased daylight passing through translucent spandrels. In heating dominated climates, such as Oslo, the aerogel granulate glazing facade does not attain the same performance as the glazing facade currently most popular, triple glazing facades. However, a combination of aerogel and triple glazing systems may offer an energy efficient facade for cold climates. From an energy saving perspective, aerogel granulate glazing systems have the potential to become a solution in not only cold climates, but also hot and warm climates. These new findings may contribute to new architecture techniques.