Experts’ interviews on the future of façade, future materials, design trends, and opportunities
INDUSTRY SPEAKS
Step into the world of architectural marvels where buildings don’t just stand tall, they inspire change. The façade of a building is not merely a barrier; it is a canvas for innovation, sustainability, and beauty. Imagine a future where every structure seamlessly blends with its environment while championing energy efficiency, financial independence, and a reduced carbon footprint.
In this era of transformation, façades play a pivotal role, bridging the gap between interior sanctuaries and the bustling world outside. They are not just walls; they’re gateways to a greener, more sustainable tomorrow.
Picture this: cutting-edge materials and designs that not only enhance aesthetics but also harness the power of nature to regulate lighting, ventilation, and thermal comfort. From dynamic shading systems to advanced cooling mechanisms, the possibilities are limitless.
But innovation doesn’t stop there. We are witnessing a renaissance in façade technology, with a myriad of systms vying for the spotlight. From modular panels to biomimetic skins, each solution offers a unique blend of efficiency and elegance.
Yet, the journey doesn’t end with today’s offerings. The horizon beckons with untapped potential, urging us to explore new materials, technologies, and design philosophies. With every breakthrough, we inch closer to a future where sustainability is not just a goal – it is a way of life.
Join us as we delve into the world of façade innovation, where creativity knows no bounds. From towering skyscrapers to humble abodes, every structure has a story to tell - a story of resilience, ingenuity, and a commitment to our planet.
So, dive into the pages of our magazine and embark on a journey of discovery. Share your thoughts, ideas, and aspirations with us, for together, we can shape a future where architecture is not just about buildings – it is about building a better world.
Enjoy the read, and don’t forget to share your feedback and suggestions at editorial@wfmmedia. com. Let’s build a brighter tomorrow, one innovation at a time.
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Performance-Based Fire Engineering - Advancing Design Strategies for Complex Buildings
Max Lakkonen, Managing Director, IFAB - Institute for Fire Safety Research (Germany)
Open Cavity Barriers Investigation
Ashwant Singh (Australia), Farith Hinojosa (Bolivia), Maria Binte Mannan (Bangladesh), and Matheus Pontes Lima (Brazil)
Exploring the Role of Acoustics in Architectural Façade Design
George Xanthoulis, Senior Consultant, AtkinsRéalis
New Generation Façades: Revolutionising High-Rise Design and Performance
Sanjeev Jahagirdar, Technical Director, Integrated Quality Services & Solutions
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The Acoustics of Façade and Fenestrations
Jacob Mathew, Senior Acoustic Consultant, Ramboll Middle East
Future Trends and Innovations in Façades
Experts’ interviews on the future of façade, future materials, design trends, and opportunities
Industry Speaks
Interview with Leonid Lazebnikov, CEO, Aestech
Face to Face
Interview with Tushar Sharma , Technical Design Lead, Woods Bagot (London Studio)
Front cover courtesy: Woods Bagot
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Max Lakkonen Managing Director, IFAB -
Institute for Fire Safety Research
(Germany)Max Lakkonen is the Managing Director of IFAB - Institute for Fire Safety Research (Germany), bringing over 20 years of expertise to fire engineering. With a background in academia in Finland, he holds a postgraduate degree in fluid power and automation engineering. Max is a well-known lecturer, often speaking at fire protection conferences and actively participating in standard committees such as NFPA 130, NFPA 502, NFPA 750, and ITA-COSUF. He also chairs the scientific council of the International Water Mist Association and serves on the MDM Editorial Advisory Board for leading fire industry publications. Max’s strong scientific background and expertise in an accredited fire test laboratory uniquely qualify him to handle complex fire engineering challenges. Specialising in performancebased design, computational fluid dynamics, and water-based firefighting systems, Max has authored over 80 publications and holds several patents.
In modern architecture, with its evolving designs, materials, and complex structures shaping urban landscapes, ensuring fire protection poses a challenge. The integration of glass façades and other glazed structures presents both technical and commercial hurdles for designers. However, an increasingly employed solution to address these challenges is performance-based fire safety design.
Architectural advancements, environmental concerns, and the integration of renewable energy technologies like photovoltaic panels pose significant challenges to fire safety in modern buildings. Traditional fire safety standards often struggle to address these complexities, highlighting the need for a more adaptable framework. Performance-based fire engineering emerges as a viable alternative, offering a comprehensive approach tailored to the unique characteristics of each building. By prioritising safety targets through flexible and innovative solutions, performancebased design strategies empower architects and engineers to navigate the intricacies of modern architecture while upholding fire safety standards.
Performance-based design in fire safety allows for the customisation of fire protection measures, departing from prescriptive codes and standards. Widely adopted in Europe, this approach offers flexibility in addressing challenges in complex buildings where standard methods may prove inadequate, such as with glass façades.
In this iterative process, fire safety engineers and designers follow key
steps outlined by organisations like the Society of Fire Protection Engineers (SFPE) or NFPA. They commence with a comprehensive analysis including various factors such as fire risks/load, materials, occupant characteristics, and evacuation strategies. This detailed analysis covers the unique needs and vulnerabilities of each building individually.
Subsequently, engineers establish performance objectives based on the analysis findings, delineating specific targets for fire safety measures. These objectives form the basis for designing customised solutions that optimise safety while considering architectural and functional requirements.
Advanced tools such as computational fluid dynamics (CFD) simulations are frequently utilised to model fire behaviour and evaluate the effectiveness of proposed measures. Occasionally, fire testing may also be conducted. This enables engineers to anticipate fire spread, assess structural exposure to heat and smoke, and evaluate occupant evacuation in various scenarios. Additionally, the operational conditions of fire services can be analysed.
Throughout the design process, collaboration with architects, builders, and stakeholders is mandatory to ensure that proposed solutions align with project goals, regulatory requirements, and budgets.
The benefits of Performance-based design for façade and glazing design (complex buildings) can be listed as follows:
• Customised Solutions: Performance-based design enables engineers and architects to tailor fire protection measures to the specific characteristics of the façade design, considering factors such as material composition, construction methods, and unique architectural features.
• Fire Modelling and Analysis: By using advanced tools like computational fluid dynamics (CFD) simulations, engineers can model fire behaviour and analyse how different façade configurations may influence/ prevent fire spread, smoke movement, and heat transfer, enabling the identification of potential fire risks and the development of targeted mitigation strategies.
• Material Selection: Performancebased design allows for the evaluation of various façade materials in terms of their fire resistance properties. Engineers can assess factors such as smoke production, and structural integrity under fire conditions to inform material selection and fire resistance decisions.
• Integration of Active and Passive Fire Protection Systems: Performance-based design facilitates the integration of both active (e.g. sprinkler and water mist systems) and passive (e.g. fire-resistant materials, compartmentation) fire protection measures within the façade design, enhancing overall fire safety performance.
• Evaluation of Evacuation Strategies: Engineers can assess how façade design impacts evacuation procedures in the
• event of a fire, considering factors such as exit routes, accessibility for emergency responders, and the effectiveness of wayfinding systems.
• Continuous Monitoring and Adaptation: Performancebased design allows for ongoing monitoring and adaptation of fire safety measures as building use and occupancy conditions evolve over the time, ensuring that fire protection strategies remain effective and compliant with regulatory requirements.
In summary, performance-based design provides a flexible and proactive framework for addressing fire safety concerns in complex building façades. By integrating advanced analysis techniques, material science principles, and innovative design strategies, engineers and architects can create façades that not only enhance the aesthetic appeal of buildings but also prioritise the safety and wellbeing of occupants and property.
IFAB has been involved in projects where performance-based fire safe -
ty design has enabled comprehensive safety assessments of complex buildings. As many buildings incorporate automatic firefighting systems, their benefits have also been utilised in glazing dimensioning. The typical fire rating of glass depends on its ability to fulfil different fire protection criteria, categorised under fire rating classes such as E and EI.
• E Classification: The “E” classification signifies integrity only, maintaining its integrity during fire exposure, preventing the passage of flames and hot gases for a specified period but lacking insulation against heat transfer (radiation).
• EW Rating: The “EW” classification includes both integrity and heat insulation properties. It signifies that the building element can maintain its integrity and provide a certain level of insulation against heat transfer when exposed to fire.
• EI Classification: The “EI” classification denotes both integrity and insulation, maintaining integrity and providing insulation against heat transfer, preventing flames and hot gases from passing
through while restricting heat transmission for a specified duration.
E, WE and EI classifications are vital for ensuring fire safety in buildings, particularly in areas where fire resistance is very important. Architects and engineers select the appropriate fire-rated glass, based on building codes and regulations, to meet specific safety standards and protect occupants & property in the event of a fire. While EI-rated glasses are favoured for most projects due to their enhanced properties, E-rated glasses offer architectural benefits with minor compromises.
Alternative solutions have been sought as performance-based design allows for diverse technological applications. One example is using the presence of an automatic firefighting system to compensate for the limitations of E-rated glass to meet EI requirements. This approach has gained interest in projects with architectural complexities or challenges in using EI-rated glass, especially in buildings equipped with water mist firefighting systems. Water mist systems, having very effective cooling capabilities, effectively suppress fires by atomising water
into tiny droplets, extracting heat and lowering temperatures. Whether for firefighting, cooling or protecting important structures, water mist systems provide an active fire risk mitigation in fire safety engineering.
IFAB has been engaged in test programmes and result assessments for performance-based design, experimentally testing glass with firefighting systems. Figure 1 illustrates a test for a glass façade according to DIN4102, but using a water mist curtain outside the furnace/glazing to provide additional cooling and blocking heat transfer (radiation). In this specific test, normal E-rated glass fulfilled EI requirements, resisting the design temperature curve for 60 minutes without cracks. Additionally, the heat radiation limit of 15 kW/m2 was met in the fire tests, which was approved by an independent certification organisation.
Performance-based design, supported by tools like computational fluid dynamics (CFD) simulations, enables the assessment of complex structures’ fire safety. For example, IFAB conducted CFD analysis for a complex atrium in
Germany, evaluating whether glass in the atrium wall could be replaced with less fire-rated glass using sprinkler or water mist systems. The selection of a water mist system, due to its superior cooling capacity, was determined through pre-studies defining the critical temperature for the atrium glass façade as 85°C.
A comprehensive assessment, including fire load measurements and validation simulations, confirmed the effectiveness of the chosen strategy. CFD simulations demonstrated that maximum temperatures on the glass surface remained below critical values, with the activation of the water mist system effectively mitigating fire risks throughout the atrium.
The simulations were even carried out with a conservative approach defining that the mist system shall not influence the heat release rate by suppressing. Using a “Freeburn” scenario, the water mist system was challenged in the most conservative way. The maximum temperatures are shown in figure 2.
Performance-baseddesign enables the customisation of fire protection measures, departing from prescriptive codes and standards in the case of very complex buildings. Engineers conduct thorough analyses, establish performance objectives, and create tailored solutions, ensuring effectiveness across different scenarios. This approach provides flexibility in addressing fire safety concerns in complex buildings, particularly those with complicated façades. It enhances overall fire safety performance through customised solutions, fire modelling, material selection, and integration of active/passive fire protection systems. Another example is the Printing Media Academy in Heidelberg, Germany (shown in Figure 3). This is one of the oldest examples in Germany where active systems, such as water mist, were used as a mitigation method to obtain the building permit for this complex structure.
Ashwant Singh (Australia), Farith Hinojosa (Bolivia), Maria Binte Mannan (Bangladesh), and Matheus Pontes Lima (Brazil) are four promising future fire engineers undertaking the prestigious International Master in Fire Safety Engineering (IMFSE). Together, they delved into the complexities of ventilated façades and cavity barriers in an internship research project with the EU-funded Fire-Safe Sustainable Built Environment project (FRISSBE) and KNAUF Insulation. The project took place in the Slovenian National Building and Civil Engineering Institute (ZAG Slovenia) facilities where the interns blended their diverse backgrounds and abilities and worked together with several stakeholders and experts in the fire field. During the project, the interns were able to visit the R&D facilities of KNAUF insulation in Slovenia, learn about standard fire testing procedures, and perform an experimental campaign to study identified influencing parameters on cavity barriers and ventilated façades. Through their study, the interns expect to contribute to the evolving research field on ventilated façades and to the understanding of how cavity barriers perform and interact when installed in a façade set up during a fire event. Moreover, the overall exposure to the fire research and fire testing fields along with the networking opportunities and the possibility to work with fire experts have been proven very beneficial to the interns who are eager to take on future research challenges.
The façade is one of the key elements of buildings across the World. Various types can be found in various countries and regions, often fitting to specific climatic conditions at the location of the building. Among various types, one can identify also ventilated facades (VF), particularly favourable in climates where water vapor transmission through a façade and prevention of condensation in the internal façade structure is of concern.
A ventilated façade (VF) system contains an airgap layer between the inner and outer membranes of the façade system. The air in the gap flows up due to buoyancy and exits the gap from the upper part while cold air enters the gap from the lower part, providing optimal thermal efficiency and moisture removal from the façade structure. In the case of fire, the presence of the air cavity in VF systems influences the overall fire dynamics of the façade. It provides the fire a pathway to spread through the inner part of the system without being noticeable.
The design of VFs can be very complex. Each type of VF is unique in its design to some extent, and therefore the fire protection mechanisms need to be tailored to fit each scenario. It is important to consider strategies that can be useful to avoid this adverse effect, for instance, the implementation of open-state fire barriers.
The open-state fire barriers (cavity barriers), allow the passage of air during normal operating conditions. The barrier itself is always made of non-combustible materials, often of fire-resistant stone mineral wool.
In the event of fire, the fire cavity barriers are closed, to create a blockage and prevent the spread of hot gases. This blocking can be done mechanically but is more often done using intumescent coatings, which expand to block any air gaps. Intumescent coating’s expansion can only sustain its weight over a small distance, thus open state cavity barriers cannot be installed in VF with large gap widths.
The choice of materials, as well as the dimensions of the air cavity, can largely influence the performance of a VF system in the case of fire.
The materials used in the insulation layer for the inner wall of the ventilated façade, as well as the cladding material for the external walls, can be either combustible or non-combustible in nature. The choice of material influences the fire performance of the entire façade system.
The effect of using combustible materials in the outer wall mainly promotes fire spread over the external wall of the system and increases the overall flammability of the system. Moreover, the external fire spread can lead to the ignition of the inner part of the façade, if combustible materials were used in the insulation layer of the inner wall. When combustible materials are used in the inner wall (insulation layer), the main effect is again the increase of the flammability of the system. The fire behavior in the inner part can be greatly influenced by the presence of the air cavity, and thus the effects of the material of the VF system are of great importance.
However, the fire performance of the façade is not only dependent on the materials present, but also on the air cavity, configuration, and
geometry of the façade. A complete assessment of the fire performance of a façade system requires the system to be tested in a large-scale test as it is intended to be used in its end state.
Being fixed to a combustible element could cause cavity barriers and fire to spread over the façade.
Cavity barriers need to be well fixed into the structure of the inner wall to guarantee functionality. Fixing elements should withstand the actions of the fire and not lose their strength under high thermal exposure.
Several factors can influence the success of such a product. Careful testing of all parameters on several scales is required to be fully confident in the final product’s success. Some of these parameters will be driven by codes and standards, but some can be completely independent of such codes.
As well as ensuring the required performance of fire barriers, manufacturers that want to design new products for any country, need to understand the market and the restrictions imposed by codes and regulations for each country.
The following table provides an overview and overlap of the main parameters requested by Germany, the UK, Spain, and the Middle East. A colour coding has been implemented to show similarities and differences. Requirements that match completely among countries are shaded with green, requirements that partially match among countries are shaded with yellow, and requirements that completely differ are shaded with purple.
Combustibility
Cavity barrier width From 20 mm to 300 mm From 20 mm to 200 mm
Position of barriers
Workmanship -
Every second floor
Edges, gaps (including above window), and every floor above the 1st
Every floor (sector) level
Workmanlike manner or certified installer -
Every floor level at the joint between the floor and around windows and doors.
Vertical barriers should be positioned.
All stakeholders involved in the construction must be licensed and registered by Civil Defense
Type of fixation Mechanical or adhesive Mechanical - Mechanical
Fixation characteristics
Non-combustible fasteners in (vertical) distances of ≤ 600 mm OR noncombustible adhesive mortar coating the full mineral wool surface adhered to the external wall
Non-combustible materials that should be able to withstand the actions of fire, and not lose their strength
Insulation
Currently, there is no harmonised European standard for the testing of open-state cavity barriers. The Association for Specialist Fire Protection has published a technical guide (TGD19) which is currently being used by industry. A new European method for testing open-
state fire barriers is currently under development.
To analyse the identified parameters influencing the implementation of open-state cavity barriers in ventilated façades
Install cavity barriers along the length of the cavity, especially when surrounded by insulation of different fire resistance
with non-combustible insulation (rock mineral wool (RMW) and glass mineral wool (GMW)), an experimental campaign was proposed consisting of bench scale tests. The general configuration of the tests is shown in Figure 1.
A testing rig was designed to simulate the conditions within a section of a ventilated façade where the barrier is placed horizontally between the inner wall (substrate) and the outer wall (cladding). The barrier is installed following the
suggested configuration of TGD 19 interrupting the layer of mineral wool insulation and under manufacturer’s guidelines.
To have a controlled environment where the testing campaign can be carried out under repeatable conditions, an SBI room was utilised. Figure 2, shows schematics of the rig with a mounted sample and a sample before being tested within the SBI room.
The heat source for the experimental campaign consisted of a propane burner with a linear configuration that fit perfectly in the middle space of the testing rig’s base. The test aimed to produce flames that were in contact with the sample’s cavity barrier to induce a high thermal load over the element. Moreover, a “flashover” like effect was sought where the flames are coming out from the window of a compartment fire and entering the cavity width of a ventilated façade.
The cavity width, air gap, and barrier height were determined according to the available product. (Cavity width: 160 mm, air gap width: 25/30 mm, barrier’s height: 75 mm)
Based on the identified trends regarding the fire resistance requirements per country in Table 1, the testing time for the samples was defined as 30 minutes in this experimental campaign. While fire resistance was not being assessed, it was considered important to capture the thermal field developed
over the sample during this time of exposure to analyse the identified parameters over a sensible time.
In total, 4 different samples were composed and tested in the
following order:
1. Sample 3, No Insulation with Splice
2. Sample 2, Glass Mineral Wool (GMW) with splice
3. Sample 1, Rock Mineral Wool (RMW) with splice
4. Sample 4, No Insulation, without Splice.
The chosen configuration of the samples was defined based on exposing the elements with their weakest point in a realistic setup. Thus, the first three samples were assembled with a splice in the middle which was protected with a fire stopping as per manufacturer’s recommendation. Moreover, the fourth sample did not count with any splice in order to compare the behaviour of the elements with and without a splice.
To capture the thermal field development over the samples, thermocouples (TC) type K were placed at the bottom and top faces of the barrier at different locations along the cavity barrier’s length. Thermocouples were also placed in the air gap to determine the temperature change after the closure of the gap by the intumescent. The configuration of thermocouples is shown in Figure 4 below.
Temperature measurements were registered at the top and bottom face levels of the fire barriers for the four samples. The measurements over the barrier were registered at four longitudinal locations: substrate joint (TCs 1,2,3,4,5,6), mid-body (TCs 7,8,9,10,11,12), air gap (19,20,21), and cladding joint (TCs 13,14,15,16,17,18). As expected, higher temperatures were recorded in the bottom face TCs of the barriers due to direct exposure to fire conditions. Top face barrier measurements of temperature increment were registered to be reduced at the joints (substrate and cladding after intumescent closure). However, different behaviours over the barrier were identified, and the RMW and GMW samples were the most interesting.
Figure 5 shows the TC measurements at the bottom and top face of the barrier for samples 1
(RMW) and 2 (GMW). The readings are at the mid-body location, it can be seen that the generated fire conditions in both sample tests induced a high heat transfer across the body of the barrier, although more severe in sample 2. The temperatures at the top face for this sample reached about 300 °C after 30 min of exposure which implies a high conductive heat transfer across the barrier promoted by the fire conditions of the test. This could imply a breach in the insulation performance of the element and need to be further investigated.
Figure 6 below, shows the evolution of the sample 2 test which resulted in the higher thermal exposure for the barrier due to the melting and collapse of the GMW and the fire conditions this event generated. A similar behavior was observed for sample 1. However, the thermal exposure was lower since the RMW block stayed intact.
The presence of insulation expedited the performance of the intumescent material compared to scenarios without insulation.
When comparing the two types of non-combustible insulation (Rock Mineral Wool, RMW; and Glass Mineral Wool, GMW), RMW offers a better performance. Fire resistance of RMW to fire-induced alterations ensures minimal changes in fire behaviour. Approximately 20 minutes after ignition, the lower RMW insulation collapsed due to weakened plastic fixations. Remarkably, post-test images revealed that the RMW remained structurally intact, displaying minor soot accumulation on exposed
surfaces. Contrastingly, Glass Mineral Wool (GMW) exhibited inward bending from the middle, generating eddy vortex behaviour within the flames. Ultimately, this generated different exposure conditions and higher heat transfer across the body of the barrier compared to the RMW insulation
The presence of splices and fire stoppers used as indicated by the manufacturer does not influence the behaviour of the functionality of the cavity barrier. This is an important matter as in construction, splices are used and should perform just as well as if the system did not have splices or joints in the cavity width. This also helps to mimic a more realistic setting for the openstate cavity barriers.
The insulation fixations are made of polypropylene and presented a melting behaviour during the experiments of Samples 1 (RMW) and 2 (GMW). Even with the collapse of the insulations, the cavity barrier still performed well and did its job of not allowing the passage of flames and hot gases. In a real scenario of a ventilated façade, the fall of the insulation must be investigated, as it can change the behaviour of the fire by falling and resting in a different position than the original one and even investigate the toxicity associated with the melting of the fixation.
The time of closure is deemed as the time of complete closure along the barrier’s length. Observations suggest that the intumescent reacts faster when the flames are closer to it. However, the intumescent reacts unevenly closing the locations with higher temperatures first.
Nevertheless, this does not affect its ability to close the gap effectively and within a reasonable timeframe.
In the case study, all the intumescent reacted in such a way that they completely closed the air gap, producing between 27 mm and 35 mm of horizontal expansion.
The experimental campaign presented here investigated the variables of insulation type and the use of splices within cavity barriers. The results presented provide some insight into the behavior of these variables, as well as establish some further variables and parameters that are recommended for investigation. The heat transfer mechanism, fixation material, effects of geometry, and the effect of the rain screen should be investigated in further work.
In the tests completed, rock mineral wool performed better when compared to glass mineral wool. Glass mineral wool is more likely to deform and collapse, potentially leading to issues around conduction across the cavity barrier. The extent of this conduction needs to be further investigated since it could compromise the performance of the element. The splice seems to have no significant effect on the performance of the cavity barrier if it is installed correctly.
The investigation was very limited, as no repetitions were made due to time constraints, and the system was only tested for a maximum of 30 minutes. The rig was also bench-scale and did not follow a standardized heating curve. It only aimed to replicate a direct exposure of the elements to flames. This may provide a lack of comparison to the full-scale installation of the fire barrier.
George Xanthoulis Senior Consultant, AtkinsRéalis
About the Author
George Xanthoulis is a Chartered Engineer with extensive expertise in acoustics and noise control. Since graduating as a Civil Engineer from the National Technical University of Athens in 2014, he has been involved in a diverse array of projects around the world, ranging from opera halls and schools to theme parks and TV studios. Currently, he holds the position of Senior Consultant at AtkinsRéalis (UK), where he oversees projects and devises innovative acoustic solutions.
In the vast and intricate world of architecture, one aspect that often does not get the attention it deserves is the acoustic performance of a façade. This element, though seemingly insignificant, plays a pivotal role in shaping the sound environment within a building. The internal acoustic conditions, largely determined by the façade, can have a profound impact on the comfort levels of the occupants, influencing their productivity and overall experience within the space.
One of the primary factors in acoustic design is the penetration of external noise into a building, also known as noise ingress. This becomes especially critical in bustling urban environments, where the levels of road noise are typically high. To address this issue, architects and designers can refer to the British Standard BS 8233. This comprehensive guide provides
valuable insights into acceptable noise levels in different types of buildings and offers reliable methods for predicting and measuring noise ingress.
In order to fully understand and anticipate the impact of noise on a building’s design, acoustic engineers often turn to outdoor 3D acoustic modelling. This advanced tool is indispensable in the field of acoustic design, enabling engineers to evaluate the effectiveness of various design strategies. With this information at their disposal, they can make informed decisions about the choice of materials and configurations, optimizing the design for superior acoustic performance.
Central to this context is the weighted sound reduction index (Rw), a single-number quantity that
encapsulates the airborne sound insulation of a building element, such as a window or door, in a laboratory setting. This value is used for selection or design purposes. It does not take into account any site particularities, such as workmanship, or how the element is connected with other elements, e.g. slabs, or junction details that can lead to sound flanking. The Rw value solely describes the main element’s sound insulation performance in an ideal, controlled environment.
Often, working alongside Rw is the spectrum adaptation term (Ctr), which provides a more accurate indication of sound insulation performance in the presence of low-frequency noise, such as traffic and music noise. The combined value (Rw+Ctr) is frequently used in specifications and regulations, offering a more comprehensive measure of a building element’s acoustic performance.
The acoustic performance of a window or façade can be significantly influenced by different glazing configurations. Architects have a range of options at their disposal to enhance the sound insulation performance of a façade. These include the use of laminated glass, which incorporates a layer of plastic for additional sound insulation; increasing the gap between glass panes; using higher thickness panes; or employing triple glazing. Each option presents its own set of advantages and trade-offs in terms of acoustic performance, thermal performance, and cost, making it crucial to consider all factors before making a decision.
Additionally, in the complex realm of façade design, internal sound transmission presents certain challenges. One such issue is flanking transmission, where sound bypasses an insulating element through paths such as mullions and transoms in curtain walls. This can pose a significant risk to the acoustic performance of a building. However, these concerns can be mitigated through meticulous design and the use of appropriate materials such as infills, or bespoke configurations, ensuring that the building achieves the desired level of sound insulation.
Striking the right balance between preventing overheating and controlling noise ingress in façade design presents an acoustic challenge. Solutions
like opening windows for ventilation can increase noise ingress. Meanwhile, keeping windows closed to limit noise can contribute to overheating. This delicate balance demands careful
consideration in the design process to ensure both thermal and acoustic comfort. This is especially relevant as net-zero building goals become more popular, making active cooling a last resort for addressing overheating. It is a fine line, but with thoughtful planning and design, it is possible to achieve a harmonious trade-off between thermal performance and noise management.
Achieving acceptable noise levels within a building is a paramount objective that requires design and execution. This is not just a matter of comfort, but also of health and well-being. High ambient noise can lead to stress, sleep disturbance in residences, and reduced productivity in workplaces. By focusing on acoustic considerations and noise control methods, ambient sound can be maintained at comfortable levels.
In conclusion, the role of acoustics in the design of building envelopes is of utmost importance. By effectively managing factors such as Rw, Ctr, noise ingress, and flanking transmission, we can create buildings that are not only aesthetically pleasing but also acoustically comfortable. This underscores the importance of involving an acoustic engineer from the early stages of design until the tendering stage, ensuring the creation of spaces that resonate with comfort and tranquillity.
Sanjeev Jahagirdar Technical Director, Integrated Quality Services & Solutions
About the Author
Sanjeev Jahagirdar has a strong progressive international experience in Quality Assurance and Quality Management functions with different projects/assignments. I have IRCA QMS Auditor ISO 9000, IEMA EMS Auditor ISO 14000, Welding Inspection CSWIP 3.1, and NDT Techniques RT/UT/MPT/LPT/VT Qualification. He has proven ability to provide leadership and critical interface between Contractor/ Company and Sub Contractors in resolving Quality issues in industrial/construction projects. He is well-travelled across the world and has experience working with the public and private sectors as well as a multitude of international Organisations and Third-party Inspection/Certification bodies like SGS, ABS, DNV-GL, Intertek Veloci, and Tata Projects.
Today’s high-rise buildings are shedding their static skins and embracing a new generation of intelligent systems that redefine comfort, performance, and environmental responsibility. This in-depth analysis delves into the world’s most widely installed cutting-edge façade solutions, exploring their general and specific design parameters, performance characteristics, and the materials shaping this exciting evolution. The future of high-rise buildings is being reshaped by intelligent façades, a new generation of cladding and glazing systems that go far beyond aesthetics. These dynamic systems integrate cutting-edge technologies to optimise comfort, performance, and environmental impact, setting a new standard for sustainable and responsive architecture.
• Sustainability: Minimising environmental impact through energy efficiency, resource conservation, and responsible material selection.
• Comfort: Optimising thermal and acoustic insulation, daylighting, and indoor air quality for occupant well-being.
• Thermal: Maintaining comfortable indoor temperatures through passive and active solar control, natural ventilation, and efficient insulation.
• Visual: Providing optimal daylighting while minimising glare and discomfort.
• Acoustic: Controlling noise pollution from both inside and outside the building.
• Performance: Enhancing structural integrity, weather resistance, and fire safety.
• Energy Efficiency: Reducing energy consumption for
heating, cooling, and lighting through optimised design and material selection.
• Durability and Maintenance: Ensuring long lifespan and minimal maintenance requirements.
• Safety: Meeting fire, wind, and seismic resistance standards.
• Aesthetics: Integrating seamlessly with the architectural design while offering visual appeal and flexibility.
• Climate and Context: The façade’s design must respond to the specific climatic conditions and surrounding environment. Factors like solar radiation, wind patterns, and temperature fluctuations need to be considered to optimise thermal comfort and energy efficiency.
• Sustainability: Utilising recycled and recyclable materials, minimising embodied energy, and contributing to positive environmental impact.
• Air Quality: Filtering pollutants and improving indoor air quality.
• Urban Heat Island Mitigation: Reducing the urban heat island effect through shading and reflective surfaces.
• Building Use and Occupancy: The façade’s functionality should cater to the specific needs of the building occupants. For example, office buildings might prioritise daylighting and glare control, while residential buildings might focus on thermal insulation and privacy.
• Material Selection: Material choice plays a crucial role in façade performance. Highperformance, lightweight, and durable materials like advanced glazing, photovoltaic panels, and kinetic elements are increasingly being favoured.
• Structural Integrity: The façade must be structurally sound to
withstand wind loads, seismic activity, and other external forces. Integration with the building’s structural system is crucial for seamless performance.
• Regulations and Codes: Building codes and local regulations regarding energy efficiency, fire safety, and sustainability must be adhered to during façade design and installation.
• Cladding and Glazing Systems: Material selection: Highperformance glass with coatings for thermal insulation, solar control, and self-cleaning properties. Lightweight and durable metals like aluminium and titanium for structural support. Ventilation: Integrated natural ventilation systems for improved air circulation and reduced energy consumption. Design flexibility: Modular systems allow for customisation and adaptation to diverse building shapes and orientations. Orientation: Optimising solar exposure for daylighting and heat gain control. Shading: Employing fixed or adjustable shading devices to manage sunlight and glare. Ventilation: Integrating natural ventilation strategies for improved air quality and thermal comfort. Material Selection: Choosing materials with high thermal performance, durability, and aesthetics.
• Dynamic Façades: Kinetic elements: Louvers, fins, or panels that adjust automatically or manually to regulate sunlight, temperature, and ventilation. Integrated sensors and actuators: Real-time monitoring of environmental conditions
• and responsive adjustments to the façade’s behaviour. Building integration: Seamless coordination with HVAC systems for optimised energy efficiency and occupant comfort.
Façade Performance: A Holistic Approach - Passive and Active Strategies
Passive Strategies:
• Double-skin façades: Creating a ventilated cavity between two layers of glazing for improved insulation and solar control.
• Green façades: Integrating living plants on the façade for natural cooling, insulation, and air purification.
• High-performance glazing: Utilising coatings and films to control solar heat gain and light transmission.
Active Strategies:
• Photovoltaic (PV) panels: Integrating solar cells into the
façade to generate renewable energy.
• Electrochromic glass: Adjusting the tint of the glass electronically to control light and heat.
• Automated louvers: Dynamically adjusting louvers to optimise solar control and ventilation.
New generation façades go beyond traditional passive strategies like insulation and shading. They actively manage factors like:
• Passive Ventilation: Doubleskin façades and operable louvers can promote natural ventilation, reducing reliance on mechanical systems and energy consumption.
• Active Ventilation: Integrated sensors and actuators can control ventilation systems based on real-time data, optimising indoor air quality, and thermal comfort.
• Daylighting and Glare Control: Electrochromic glazing and
louver systems can adjust to optimise daylighting while minimising glare, improving occupant well-being, and reducing lighting energy use.
Material Innovation: Efficiency, Economy, and AestheticsEfficient, Economical, and Attractive Façade Materials
• High-performance glass: Low-emissivity (Low-E) glass, electrochromic glass, and vacuum-insulated glass offer excellent thermal performance and aesthetics.
• Metal cladding: Aluminium, steel, and titanium offer durability, weather resistance, and recyclability.
• Composite materials: Combining different materials like metal and wood can achieve unique aesthetics and performance characteristics.
• Bio-based materials: Bamboo, cork, and other sustainable
materials offer eco-friendly options with good insulation properties.
The material landscape for façades is rapidly evolving, offering exciting possibilities:
• Photovoltaic Glazing: Integrated solar panels in the façade generate clean energy, contributing to the building’s energy independence and sustainability.
• Dichroic Glazing: This selective glazing filters specific wavelengths of light, allowing for enhanced thermal insulation and daylighting control.
• Intelligent Glazing: Electrochromic and thermochromic glazing dynamically adjust their tint in response to environmental conditions, providing optimal comfort and reducing energy consumption.
• Kinetic Façades: Moving louvers and panels adapt to changing sun angles and wind patterns, optimising solar heat gain and ventilation.
• Bio-inspired Materials: Selfcleaning façades with lotus effect surfaces and self-healing concrete are being explored for improved performance and reduced maintenance.
• Photochromic glass: Adapts its tint in response to sunlight intensity, reducing glare and heat gain while maintaining transparency.
• Electrochromic glass: Switches between clear and opaque states electronically, offering privacy control and solar heat gain management.
• Bio-inspired materials: Selfcleaning surfaces that mimic lotus leaves, and photovoltaic panels integrated into the façade for energy generation.
• Lightweight composites: Highstrength, low-weight materials like carbon fiber composites for improved structural performance and reduced energy consumption.
New generation façades are transforming from static elements into dynamic interfaces:
• Information Sensitivity: Sensors gather data on temperature, light, and air quality, informing adjustments to the façade’s behavior. Sensors embedded in the façade collect data on environmental conditions, occupancy patterns, and energy use, informing realtime adjustments for optimal performance.
• Communication & Interaction: Façades can display information, project images, or even generate electricity through integrated photovoltaic panels. Façades can display information or even act as interactive interfaces, engaging with occupants and the surrounding environment.
• Self-Cleaning Façades: Nanocoatings and specialised materials repel dirt and dust, reducing maintenance needs and improving air quality.
• Environmentally Dynamic Façades: Responsive to changing weather conditions and occupant needs, optimising comfort and energy efficiency. Façades can adapt to changing environmental conditions, such as adjusting ventilation rates based on air quality or providing shading during heat waves.
Beyond the focus on comfort, performance, and environmental parameters, the next generation of façades is venturing into exciting new territories:
• Self-cleaning: Nano-coatings repel dirt and grime, reducing maintenance requirements.
• Environmentally dynamic: Façades adapt to changing weather conditions through responsive materials and systems.
• Information-sensitive and communicating: Sensors and actuators collect and respond
• to data from the environment, optimising performance and interacting with occupants.
• Transparent yet photochromic: Glass that changes tint based on light conditions, providing both daylighting and glare control.
• Lightweight yet strong: Advanced materials offer high strength-to-weight ratios, reducing structural loads.
• Safe without additional processing: Inherently safe materials eliminate the need for additional safety measures.
• Energy generation: Integrated PV panels and other renewable
energy technologies power the building and beyond.
Parametric façades use algorithms to design and optimize their form and function based on specific parameters. This allows for:
• Sustainability: Minimizing material usage and energy consumption through optimised design.
• Power generation: Tailoring the façade to maximise solar energy capture and conversion.
• Vertical farming: Integrating hydroponic systems into
for urban food production.
• Balancing cost with performance remains a key challenge. However, advancements in material science and automation are driving down costs and making these intelligent systems increasingly accessible. As technology evolves, we can expect:
• Fully integrated responsive façades: Seamlessly adapting to real-time environmental conditions and occupant needs.
• Biomimetic façades: Façades mimicking natural systems for enhanced performance and sustainability.
• Hyper-connected façades: Integrating with smart building technologies for a truly holistic building experience.
• Cost-to-Performance Balance: Balancing the upfront cost of advanced technologies with their long-term performance and energy savings is crucial for wider adoption.
• Integration and Complexity: Seamless integration of diverse technologies and sensor networks into the façade system
requires careful planning and execution.
• Standardisation & Regulations: Establishing clear standards and regulations for safety, performance, and data privacy associated with smart façades is crucial.
Despite these challenges, the future of façade technology is bright. As research and development efforts continue, we can expect even more innovative and intelligent façades that blur the lines between building skin and living organisms, responding in real-time to their surroundings and creating truly sustainable and responsive high-rise environments.
The vision of a façade as a living skin, responding and adapting to its surroundings, is no longer science fiction. These intelligent systems are poised to revolutionise the way we design, build, and experience our high-rise environments. From optimising comfort and energy efficiency to fostering a connection with the natural world, the future of façades promises a more sustainable, responsive, and ultimately, human-centric built environment.
Here are some additional insights and resources you might find helpful:
• Case Studies: Explore realworld examples of highperformance façades in action, such as the Al Bahr Towers in Abu Dhabi or the 1 Bligh Street building in Sydney.
• Research and Development: Stay updated on the latest
advancements in façade technologies through organisations like the Council on Tall Buildings and Urban Habitat (CTBUH) and the International Passive and Low Energy Architecture (IPLEA) conference.
• Visualisation Tools: Utilise software tools like IES VE and Ecotect New Generation Façades: IES Virtual Environment (IESVE) and Ecotect New Generation Façades are software tools that can help architects, engineers, and designers create energy-efficient and environmentally sustainable buildings. Ecotect is a building performance simulation software that can calculate a building’s energy consumption by simulating its context within the environment. It is designed to help architects, engineers, and designers create buildings that are not just aesthetically pleasing but also highly energyefficient and environmentally sustainable.
Visualisation Tools ESVE and Ecotect are a suite of applications for building performance analysis. It can be used to:
• Test different options
• Identify passive solutions
• Compare low-carbon and renewable technologies
• Draw conclusions on energy use, CO2 emissions, and occupant comfort
• Model, predict, and verify performance throughout a building’s life cycle
• Evaluate architectural designs holistically
• Consider outcomes for enhanced daylighting status, occupant thermal comfort, natural ventilation, and reduced carbon emissions
Jacob Mathew Senior Acoustic Consultant, Ramboll Middle East
About the Author
Jacob Mathew is an engineer with an honors degree in Architectural Engineering and a Masters in Energy. With over 4 years of experience in acoustic consulting, he has successfully managed diverse projects across the Middle East, Australia, and South Korea. Jacob is an Associate member of the Institute of Noise Control Engineers, the Acoustical Society of America, and an Affiliate member of the Institute of Acoustics. His project portfolio spans various sectors, including hospitality, residential, commercial, offices, mixed-use, entertainment, cinemas and recording studios. His professional ability extends to project management and client relations, showcasing a comprehensive skill set in delivering acoustic solutions for a wide array of architectural endeavours on a global scale. Jacob is currently working as a Senior Acoustic Consultant at Ramboll Middle East’s specialism team.
As cities continue to grow, the need to mitigate external noise and enhance indoor acoustic quality has become paramount. The criteria for acoustic comfort have evolved into a necessary consideration in habitable spaces. Several studies have investigated the connection between noise annoyance and both the physical attributes of sound and its impact on health and wellbeing. Noise nuisance has shown to adversely affect hypertension, increase chances of cardiovascular diseases, increases stress, and reduce cognitive efficiency in occupants [1].
An acoustically comprehensive strategy for occupant comfort in buildings often involves a multifaceted approach, incorporating design concepts, material selection, and the expertise of acoustic consultants to achieve optimal results. However, in pursuit of streamlined green and sustainable strategies, the acoustic wellbein of the users of the space often goes unnoticed. For instance, a study on indoor environmental quality (IEQ) involving 23,450 respondents from 142 buildings concludes acoustic nuisance as the primary concerns in LEED certified offices [2]. This scenario can be avoided through thoughtful consideration and a touch of creativity. It is possible to merge the objectives of sustainability and acoustics and create a facility that is both functional and sustainable.
Even in residential buildings, acoustic complaints rank among the top three dissatisfaction measures from occupant post-occupancy evaluations (POEs). Looking at the physical characteristics of sound, residents primarily express annoyance with various noise sources, including noisy neighbours,
traffic, and construction. The building envelope becomes the primary form of protection for the residents from the urban soundscape. Then, the acoustic performance of a building façade is a critical aspect to consider in providing a comfortable living space for occupants.
The Acoustic performances of façade systems are generally given in STC, OITC, R w or R w +C tr ratings. Understanding key acoustic metrics is crucial in evaluating the acoustic performance of façades.
Sound Transmission Class (STC) is a US metric that measures the ability of a material to impede the transmission of sound. Similar in most ways to STC, the R w (weighted sound reduction index) is an International Standard Organisation (ISO) metric that assess the airborne sound insulation performance of a system. Both these rating usually provide similar numbers given there are no substantial peaks or troughs in the transmission loss (TL) spectrum.
However, when specifying façade acoustic criteria, it is important to consider the extended frequency
performance of the system for appropriate design.
The outdoor-indoor transmission class (OITC) rating was created in the late 1980’s within ASTM as a standard classification in response to a perceived need for a more robust metric that adequately considers low-frequency incident sound. The OITC is usually 5 to 10 dB lower than STC. This type of noise is dominant near highways, airports, or mechanical plants. The International Standard Organisation (ISO) also provides a similar single number rating denoted as R w +Ctr. The C tr is an additional spectrum correction that focuses on low frequencies, primarily transport and industrial noise.
All these metrics are laboratory measured indices that are tested under controlled conditions. In most cases, a reduction in the range of 5-10 decibel points can be observed between lab and onsite test measurements, primarily due to flanking paths and quality of workmanship on-site.
Glazing build-up is one of the key properties that determines the performance of a glazed
façade system. As glass is a stiff limp mass, they tend to follow the ‘mass law’ where the sound insulation performance of a system is directly proportional to its mass per unit area. Doubling the airgap is expected to give an improvement of around 3 points in R w/STC rating.
For a specific frequency, the air gap tends to reduce the performance of the system due to ‘Mass-Air-Mass resonance’ effect. In this frequency, the air will effectively act as a spring that will easily transfer noise. One of the ways to adjust this dip in performance is to increase the air gap, which tends to move this dip towards the low frequencies, away from the sensitive audible spectrum.
The materials used in the façade system, such as glass and aluminium, possess an inherent ability to vibrate at specific frequencies referred to as their ‘natural frequency’ or ‘coincidence frequency’. For glazing systems, this frequency depends on the nature of the glass, its dimension, its fittings and installation. Noise impinging on the glazing at their natural frequency range will pass through with little attenuation and will form a dip in their acoustic performance spectrum. This is known as the ‘coincidence effect’.
The coincidence effect is of particular concern since the
coincidence frequency of glass usually corresponds with the nature of high-frequency noise from traffic, aircraft, etc. If not designed appropriately, these noises can be heard through the façade system. Opting for varying glass thickness in a double-glazed system can remedy this effect to a considerable level. This will ensure that the transmission loss is flattened and spread to not occur drastically over a specific frequency.
These effects discussed above can be observed in Figure 2, along with QR codes to scan for audio files. A difference of 3 decibel points is rarely perceivable, and the sensitivity of people varies. These
audio files are provided to try to find some perceived difference in level drop from a source and also if possible any frequency response differences between the systems by the listener.
A laminated glass is a type of safety glass composed of two or more layers of glass bonded together with a transparent and flexible interlayer, typically made of polyvinyl butyral (PVB). An improvement of 1-3 points is generally expected from a typical PVB laminate system depending on the number of layers between the glass.
Furthermore, specific laminates focused on sound insulation capabilities are also developed by various glazing manufacturers that can offer an improvement of at least 3 dB or more from just a single layer of laminate & can also have specific transmission control over frequency ranges. Due to their unique nature, they are relatively expensive and are used only in specific situations if necessary. The inclusion of lamination in a glazed façade also changes its visual essence depending on the lamination thickness.
Although not as critical as a Shakespearean dilemma as the title suggests, the selection and inclusion of laminated glass in the façade requires some thought. A well-coordinated strategy with the acoustic consultant and the design team is required when prescribing laminated glazing systems. The solution should ideally maintain the visual uniformity and architectural design intent of the façade.
The performance of a building façade is usually determined by
multiple elements, including glazing, walls, windows, spandrels, and other similar components. In a composite façade, the overall acoustic performance of the system is effectively determined by its acoustically weakest insulating element. In a scenario for a room where, if around 30% of a façade area is glazing with R w /STC 35 dB performance and the remaining is blockwork of R w/STC 45 dB, the composite performance will effectively be around R w /STC 40 dB. You may expect a 1-2 point improvement by increasing the blockwork acoustic performance, but nothing more.
In reality, given the weakest element covers around 10% to 40% of the total façade area, increasing the performance of surrounding elements by 10-decibel points or more than the weakest element’s acoustic performance provides little to no improvement in the composite performance of the façade.
A façade system specimen presented for an acoustic test must include all fittings and frames exactly as how it would be constructed on-site. Separate tests of individual façade elements will not confirm
the performance of the composite façade system. If individual performances and dimensions are known, an estimated performance can be calculated using the methodology provided in BS 8233. However, this cannot validate the composite system’s performance instead of a certified acoustic laboratory test.
Flanking is the transmission of sound through alternate paths or unintended routes due to improper detailing or on-site conditions. Any fittings or fenestrations on the façade can bring down the performance of a façade drastically due to flanking even if the glazing is of superior performance.
In high-rise curtain wall systems, the usual points of flanking are through mullion cavities, slab edge connections, spandrel points, cladding cavities, etc.
The first step is to identify possible flanking paths over a section detail and provide an acoustic block to the path, typically using a few layers of plasterboards & some mineral wool between cavities. This may not be a suitable option in all cases, as they
may not align with the design intent. Another solution is to provide cavity inserts in the mullions or transoms between spaces. This application has its drawbacks when considering the complexity and labour involved in actualising this on-site or otherwise. Some illustrations are provided to show possible flanking paths and good design practices to treat them.
The perimeter seals, jambs, drop seals, cavity fillers, etc that are involved in the installation and workmanship of fenestration can impact the overall performance of a building façade greatly. Applying foam, sealants, or other materials to fill gaps between the window frame and the rough opening has the
potential to effectively reduce sound transmission to a satisfactory level.
ASTM C919 focuses on the critical task of sealing small gaps between material interfaces to reduce the ease of sound transmission. The presence of a “hiss” noise or a dip in the mid to high-frequency range through the façade generally indicates poor sealing around the system.
Façade acoustics is essentially a balance of design engineering, material quality, workmanship, and acoustic expertise. Collaboration between architects, façade engineers, and acoustic consultants is essential to achieve a harmonious balance between aesthetic appeal
and optimal acoustic performance of façades. By incorporating sound insulation strategies from the conceptual stage, designers can create buildings that not only stand as architectural marvels but also provide a quiet and comfortable sanctuary amidst the urban jungles.
1. E. B. E. O. L Barregard, “Risk of hypertension from exposure to road traffic noise in a population-based sample,” Occup Environ Med, vol. 66, no. 6, pp. 410-5, June 2009.
2. C. Curtland, “Acoustics: The Biggest Complaint in LEEDCertified Office Buildings,” Buildings, 21 August 2012.
“Future Façades Shall be Seeing Rapid Integration of Renewable Energy Technologies, such as Photovoltaic Panels or
ANIKET DESHPANDE Façade Consultant, Thomas Bell-Wright International Consultants
• As smart building technologies become more prevalent, how do you see façades integrating with these systems to enhance overall building performance?
Smart technologies today are not just prevalent but have become an integral part of our lives. With apps
controlling the lights, air-conditioning, entertainment, coffee machines, and whatnot, building fenestrations are not untouched by smart technologies today.
From integrated blinds within IGUs, digitally controlled and programmed electro-chromatic glass products, to dynamic shading devices that can change orientation, position, and location, to daring adventures where roofs and façades are designed to function dynamically to control light and visibility, façades have come a long way. All these features being connected to building automation and maintenance systems make it even more relevant today.
Apart from thermal performance, intelligent smoke and ventilation systems involving façade automation, which are triggered in case of emergencies to help mitigate fire risks elevate the building performance above and beyond the safety offered by conventional passive systems.
AI-enabled thermal detection camera-controlled fire hoses tackling localized façade fires over façade have also been experimented with, where strategically placed firefighting systems over the building face detect localized façade fires and extinguish them within critical time to avoid further spread.
• What innovative materials do you anticipate will play a significant role in the development of future façades?
The choice of materials is endless when it comes to façades. What is exciting today, is that product innovation in materials has moved beyond offering 'pretty looking'
materials to sensitive choices which helps the designers and developers meet their core principles while delivering the projects.
With the sensitivity toward the environment, leading manufacturers are offering recycled glass and aluminum products. With leading glass manufacturers finding ways to increase the cullet and system manufacturers introducing systems using up to 75% recycled aluminum, such as in the case of the Technal CIRCAL series, designers have a choice, to begin with low embodied carbon for the two major components of contemporary façade systems.
From a thermal performance point of view, the availability of high-performance glazing with low-iron glass and triple silver coatings helps designers meet their performance goals without compromising on aesthetic quality. Advancements in ceramic fritting and digitally printed glass allow designers to control the window-wall ratio without compromising on the glazed area and material pallet. Thoughtful frit patterns over façades based on the sun's path can help maximize the daylight while keeping the harsh sun away.
Laminated glass and the range of interlayers have started to play an important role in how glazing is looked at. From imparting different qualities such as translucency, color variations, acoustic performance, structural performance, and safety toward blast-proofing and bulletproofing while maintaining clear visibility, PVB and SGP interlayers are changing the way glass is used in contemporary buildings. Building integrated photovoltaic panels are also being integrated within the façade.
• What are the essential tools used in the creation of future façades?
Façade development has three crucial phases – the vision developed by the Architects, the development of façade solutions with systems that can meet this vision, and the fabrication and installation stage which makes this vision a reality. All these three phases demand different tools and different attention at every stage.
With the future of design heavily relying on parametric and generative design principles, a large set of dedicated software as well as plugins are helping
designers envision building skins that optimize environmental performance and push toward a sustainable built environment. With BIM being the industry standard and the way forward, the design information is loaded in at a nascent stage.
Façade models are then further detailed to capture the system nuances, material characteristics, and performance parameters, which can be analyzed in the larger building model to simulate the results, allowing further tuning to achieve established performance goals. Calculations for embodied carbon, impact on MEP, costing and value engineering, material optimization, and quantification can all be done within the BIM environment.
Beyond this point, the fabrication and installation discipline, popularly called the contracting world has a different set of tools that are gaining higher ground on innovation as compared to the digital counterpart. Fabricators and system manufacturers are investing in multi-axis CNC machines which can be programmed to process façade components from a simple extruded profile to a fully fabricated set of parts ready to assemble with strictest of the tolerances and high-quality control. Metal 3D printing is gaining popularity within the industry with innovative systems such as Schueco's 'Grid2Shell' and Technal's 'Tental Parametric Façades systems.
• Can you provide insights into the recent advancements in façade and cladding technologies, including materials and construction methods?
With an everchanging building landscape and a constant stream of innovative and unique design
solutions by Architects, façade and cladding materials as well as the methods of putting them together are in constant development. The industry is majorly moving toward pre-fabricated site-installed façade systems for the correct reasons, and integrating, transporting, hoisting, installing, and testing such systems is increasingly challenging. Pre-fabrication and unitization of façade systems reduce the work on site and help in maintaining the quality of façade systems at the fabrication facility. It also helps reduce the time required, as fabrication happens parallel to the construction at the site, and reduces the site-associated risks.
Given the increasing focus on sustainability, future façades shall be seeing rapid integration of renewable energy technologies, such as photovoltaic panels or solar-integrated cladding. While roofs have been engaged before for the installation of photovoltaic panels, the limited area available which is shared with other building services considerably reduces the available surface area. With the advent of HighTransparency Window-Integrated PV panels, Façades can generate energy, helping decarbonize the built environment.
• Could you share your favorite façade material and explain the reasons behind your preference?
I would love to answer that as an Architect, but as someone helping fellow designers to take their design intent to a built product, I am unfortunately not allowed to be biased for or against materials and systems and tend to choose a material or system that can achieve the best results for the proposed design intent. The projects I find interesting are the ones where the qualities and strengths of a certain material or set of materials are capitalized to achieve a thoughtful design intent.
• What features would you like to see incorporated into future façades to enhance their functionality and aesthetics?
Façade industry is dynamic and we're all learning new things every day. At an early design stage, the designers need to understand the available materials, their strengths, and their limitations. Considering available stock sizes of materials to optimize their usage at early design stages can help achieve ‘zero waste’ façades.
Performative testing and the use of certified materials in façade are equally important to ensure anticipated results. With the constant flow of attractive materials entering the market and the excitement of designers to build something unique, it happens far too often that materials that are not tested for their performance make it to building façades. Their reaction to fire, weathering, and integrity when installed within a defined façade system remain questionable and their use might unfortunately be a calling for undue events risking life and safety. Performative mock-up tests also enable designers to empirically establish the performance of façade systems and fix any shortcomings before application over the actual project.
When it comes to functionality, it is important to note that façades need timely cleaning and maintenance. It happens far too often, unfortunately, that the façade access and maintenance systems for even large projects are completely ignored and the developers just end up delivering a pretty building. Proportionate investment in appropriate BMU systems is pivotal to a functional and durable façade, which looks good and functions well throughout the building life-cycle and not just the first few months.
• How does automation play a role in façades and fenestration, and what are the associated benefits of incorporating automation in building exteriors?
Today automation by far is largely limited to home interiors, with a lot of system manufacturers now offering motorized door and window systems. As dynamic façades along with façade lighting and modern glazing materials start gaining traction, the skin systems will be much beyond a static set of materials. Buildings will be programmed to be more 'climate reactive' than 'climate-sensitive'. With the integration of automation and artificial intelligence in every aspect of our lives, façades will soon enjoy the benefits of the digital revolution with the integration of dynamic components.
• What are the key Characters of a HighPerformance Façade?
High-performance of façades is primarily associated with their thermal performance – may it be avoiding radiant heat or trapping the embodied heat within a building depending on the location of the project. While thermal performance is the key driver for highperformance façades, other aspects such as durability, fire performance, safety, air tightness, resistance against water permeability, the integrity of materials, quality of finishes, and compliance with international codes and standards – all contribute toward making a HighPerformance Façade.
Demands from façade are becoming more complex as standards keep on updating. Nations and cities are gearing up to implement stringent codes and standards addressing the performative aspects of façade systems. Façade systems employed on the projects should meet and exceed the international standards as we progress.
• In the context of climate change, how can façades be designed to withstand extreme weather conditions while maintaining their aesthetic appeal?
We have all seen faded colors of once bright-colored shopfronts around town, which were novel a decade or two ago, deformed cladding panels, dislocated louvers, and stained glass canopies with rust streaks from spider fittings. Although the aging of a building is not completely avoidable, modern materials, if chosen wisely and installed correctly, can last longer in worsening weather conditions.
It is important to choose the correct coating for exposed aluminum cladding and extrusions meeting international standards. Choice of the right hardware, fasteners, gaskets, and silicone compatible with materials in contact, bi-metallic separation, proportion of panels, and making sure the systems are designed to withstand the anticipated wind loads are a few factors that are vital while designing façade systems.
Performance glazing plays a vital role in addressing the extreme weather and innovation in high-performance glazing shall lead the path for how the industry reacts to climate change.
• As urban spaces become more interconnected, how might façades contribute to creating a sense of community and connectivity within and between buildings?
From the digital screens of Times Square, the celebratory face of Burj Khalifa, exterior green walls of Singapore, to sculpted honey-comb curved columns and canopies of Mumbai Airport, façades all over the world can define a sense of place and affect everything that happens around them.
While the experiential quality of architecture can be overwhelming through its spatial characteristics, the first relation a user makes with a building is from the exterior. Façades make the first impression on the user. With designers paying more importance to integrating interior and exterior by blurring the boundaries, building skins are becoming more permeable in nature. Designers are expecting performance glass products with higher light transmission while retaining the thermal performance. As designers continue to blur these boundaries, façades need to
be extremely flexible while providing the necessary protection and performance.
• How do you envision the future of façade design, considering the evolving technologies and materials in the field?
With conventional architecture where the structure, fenestrations, and finishes were indistinguishable and designed as a larger system forming the external building wall, façade design as a specialized discipline barely existed. Façade meant the 'exterior road facing side of a building'.
With evolving building technology, the advent of new materials, and the growing general scale and pace of construction, façade design has found a new meaning. Today, façade systems serve as the primary and many times the only barrier between the inside and outside, hence making it necessary for them to be robust from structural, environmental as well as safety perspectives. Façades need to perform all the functions of a conventional external wall, along with imparting a unique and contemporary appearance to the structure.
We see the construction industry move toward a modular approach as we progress, and the integrity, performance, and novelty of façade systems are becoming more critical than ever. It therefore requires expertise not just limited to Architecture or Façade systems in isolation, but to a more holistic outlook, where façade engineering meets façade design leading to better performing, durable, safer, and 'Future-ready Architecture' reminiscing from where Mies Van Der Rohe sparked the early dreams of glazed façades with his early curtain wall experiments in Chicago, preaching that 'God is in the details.'
“The Future of Façade Design will have a Greater Emphasis on Sustainability - Greater Energy Efficiency, Lower Embodied and Operational Carbon as well as Higher Resiliency”
RAKSHA MAGAL Façade Consultant, Heintges Consulting Architects & Engineers
• As smart building technologies become more prevalent, how do you see façades integrating with these systems to enhance overall building performance?
Integration of façades with smart building technologies has been happening for a while now. The most
prevalent example is the integration of shading systems with BMS (Building Management Systems and BAS (Building Automation Systems). This includes internal shading such as blinds and louvers as well as external shading as a part of kinetic façades. Smart glass is also becoming quite popular. Smart glass is one whose VLT (visible light transmittance) changes depending upon external conditions. All of these have served to help façades improve user comfort and energy efficiency of the overall building. The next step in the process of façade integration with building automation that we can hopefully look forward to is the reduction in risks and costs associated with the same. Improvement in data collection and sensors to allow façades to react quicker and more efficiently to external environmental changes would be a huge benefit to façade automation. Relying on renewable sources of energy such as solar or wind energy could help reduce the overall energy usage of façade automation.
• What innovative materials do you anticipate will play a significant role in the development of future façades?
The building industry constantly sees an influx of new and innovative materials that perform better or provide a better aesthetic. The same is true for façades. Over the past few years fiber reinforced composites have become popular as a building material with the main advantage being high strength-to-weight ratios. FRP (fiber-reinforced plastics) and GFRC (Glass fiber reinforced concrete) are now commonly integrated into façades either as a rain screen panel or as the primary weather barrier itself. UHPC (ultrahigh performance concrete) is another such material
whose use has been gaining traction over the past few years. Its high tensile strength allows a reduction in material quantities by approximately half compared to traditional precast concrete. With the growing understanding of the importance of materials with low carbon footprints, UHPC offers all the benefits of precast concrete with half the amount of material. While on the topic of low embodied carbon materials, the R&D groups of the façade industry have turned their attention to interesting new types of insulation such as sustainable insulation panels made of mycelium fungi. Aerogel blankets and vacuum insulation panels are now being used to achieve high R-values in limited spaces. Traditional materials like glass are also seeing innovations like VIG (vacuum insulating glass). With the focus turning toward adaptive reuse of existing buildings, these materials with their high R-value per inch, could solve problems of limited space while still achieving high performance.
• What are the essential tools used in the creation of future façades?
Design and simulation software have always been at the heart of the façade industry. With the growing importance of high-performance façades some of
the new tools that we can look forward to include improved precision in thermal modeling including three-dimensional thermal modeling. Many local codes and certifications now require accurate quantification of thermal bridges to understand and study the energy loss associated with each thermal bridge. Threedimensional modeling could play a huge role in this. CFD (computational fluid dynamics) has always been used in the façade industry. More active usage of CFD could help with accurate simulation of exterior wind conditions on façade geometry (especially in projects that do not have a wind tunnel study) as well as study the effect of perimeter diffusers and fin tube radiators on façade performance. However, the biggest asset the façade industry has is designers who understand the need to adapt and design façades sensitive to climate change, carbon footprint reduction, and energy efficiency.
• Can you provide insights into the recent advancements in façade and cladding technologies, including materials and construction methods?
Unitisation of façades has now become commonplace. Unitised façades allow for greater quality control
and precision in fabrication. It minimises the risks of onsite installation. Another aspect of the façade design process that greatly improves the performance and quality of façades is Performance Mock-up (PMU) testing. PMU testing involves simulation of worst-case movements, structural loading, air, and water infiltration as well as freeze-thaw cycling of a representative part of a façade. This allows designers and contractors to foresee potential problems in façade design, fabrication, assembly, and trial installation. Construction administration has improved over the past few years. Inspection and commissioning of façades have helped improve the performance and quality of façade systems. In terms of materiality, one of the biggest advancements is thermally broken façade systems. Thermal breaks in the form of poured-andabridged polyamide components are now a common part of high-performance curtainwall systems. Rainscreen façade designers now have the option to specify non-metal (e.g. fiberglass) brackets for support of rainscreen panels and insulation. These and many other similar advancements allow for lower U-values of façades.
• Could you share your favorite façade material and explain the reasons behind your preference?
My favourite façade material is the timeless classicGlass. From stained glass windows of Gothic churches to modernism proclaiming glass as a miraculous means of restoring the law of the sun, glass has always been an expressive feature of architecture. The material is extremely versatile in terms of aesthetics. From clear flat plate glass to cold bent glass, textured glass, curved
glass, and more - the possibilities are endless. In terms of the performance of glass as a façade material, the advancements are never-ending. Double-insulating glass units (DGUs) have given way to triple-insulating glass units (TGUs) in multiple projects across the world. Vacuum insulating glass (VIG) is now becoming readily available in the market. A wide range of Low-E coatings helps achieve low U-values. The use of interlayers in laminated glass also allows for a new range of aesthetics including lamination of fabric or mesh between two pieces of glass. Laminated glass also offers the benefit of safety glazing and even ballistic glazing.
• What features would you like to see incorporated into future façades to enhance their functionality and aesthetics?
For future façades, I’d like to see more incorporation of dynamic shading systems like active louvers or kinetic shading elements which can respond to environmental conditions like sunlight and weather. There have also been research projects that explore “living façades” - façades that can support vertical gardens and improve urban air quality. This would be a wonderful challenge for façade designers to explore.
In terms of functionality, I would like to see the façade industry implementing rules of good practice such as continuous insulation, thermal breaks, continuity of air seal, etc. across the board for all projects, regardless of budget.
• How does automation play a role in façades and fenestration, and what are the associated benefits of incorporating automation in building exteriors?
The role of automation in façades and fenestration has increased over the years. Today automation is used in façades to control shading systems such as roller blinds. Automation is also key to the performance of “smart” glass - glass that changes its VLT (visible light transmittance) based on external weather and sunlight conditions. Automated ventilation systems help achieve active ventilation through façades and help improve energy efficiency and user comfort.
• What are the key characteristics of a HighPerformance Façade?
Based on my experience in the façade industry I have learned a few key rules that can make or break a façade.
This includes multiple layers of defense - generally in the form of weather and air seals. Continuity of air seal is extremely important to prevent unplanned air and water infiltration. Anticipating paths of potential failure and accommodating the same in a controlled manner makes for a good façade design and this is the basic idea behind a pressure equalised system. The cavity between the air and weather seal is pressure equalised to the exterior allowing for water and air to exit this cavity through weeps and vents in the weather seal. Coordination between adjacent trades is often a challenging aspect of construction and design in the façade industry. Paying particular attention to and ensuring robust tie-ins at perimeters can help create a well-performing façade. Continuous insulation and consciously minimising jogs or breaks in the plane of insulation and glazing in the early stages of design is particularly important, especially in colder climates. All façades, whether structural (load-bearing) or non-structural will experience movement - thermal movements, seismic movements, differential movements, etc. Accommodation of movements is crucial in the design of façades.
• In the context of climate change, how can façades be designed to withstand extreme weather conditions while maintaining their aesthetic appeal?
Façades are the skin of buildings. They are first the layer of defense against external weather conditions. This also makes them the most vulnerable to energy loss to the exterior. In the context of climate change, it is now more important than ever for façades to be adaptable and capable of withstanding extremes of temperature, wind, and other weather phenomena. As façade designers, we can explore ways to incorporate passive and energy-efficient means of cooling and shading of façades. Façades should also be designed with thermal efficiency in mind. Building codes are now becoming more stringent and the prescriptive U-values are becoming lower with each new edition. 50 and 100-year storm events are now becoming frequent, requiring façades to be designed to withstand higher structural loads. Architects across the world also understand the importance of reducing in carbon footprint of the construction industry. As façade designers, we must evaluate every material choice and design decision to weigh its global warming potential.
• As urban spaces become more interconnected, how might façades contribute to creating a sense of community and connectivity within and between buildings?
Façades play a major role in the rich urban fabric of cities across the world. Façades often incorporate multiple
scales. For example, a unitised curtainwall on a tower flows into the human scale at the street level in the form of storefronts nestled under canopies. This helps create a different sense of community from the street to the skyline of a city. Differing levels of transparency of façades is an important feature of cities - this helps transition from an inward focus within the building to an outward focus on the neighborhood around. Welldesigned façades offer a clever distinction between the indoors and outdoors and can blend seamlessly from one to the other. Concepts like Privately owned public spaces (POPS) have successfully been explored in multiple cities across the world. Façades play a major role in POPS - storefronts opening into arcades, atriums carved into lobbies, and canopies swooping over a semi-outdoor seating area. Façades also offer a canvas for digital displays of art, advertisements, and public information in cities.
• How do you envision the future of façade design, considering the evolving technologies and materials in the field?
The future of façade design will have a greater emphasis on sustainability - greater energy efficiency, lower embodied and operational carbon as well as higher resiliency. High performance has already started to become the norm of the façade industry and hopefully, façades will continue to evolve in this aspect. We will see the advent of new and innovative material in the future. Above all, hopefully, the future of façades holds inspiring and thoughtful designs that will leave us all in awe.
“The Demand for Environmental Friendliness is still Very Strong, and Our Product Meets all the Current Requirements”
About the Author
Leonid Lazebnikov CEO, AestechLeonid Lazebnikov is the CEO of Aestech. Aesthetic Glazing Technologies. They are reimagining the glass façade and changing the role of glass from a filling element to an independent system of enclosing structure.
In a conversation with Window & Façade Magazine, Leonid talked about the journey of Aestech, their products & and projects, major challenges façade in the industry, and so on. Here are the excerpts…
Could you please share the journey of Aestech since its inception?
The history of Aestech began long before the company with this name was founded, namely with the emergence of frameless glazing technology using highstrength double-glazed windows in 2007. Over time, we have attracted more and more supporters of our solutions based on high-strength glass units. As a result, we have now grown into a company with a close-knit team, a line of high-tech products, and several offices and representative offices in different countries and on different continents.
What are the products you offer?
We do not offer products, but solutions using our products. A client comes to us with a request, and we develop a solution for them that would best suit their idea or project. Unlike other companies, we don’t tell our clients “no” or “it’s impossible to implement”, but instead look for ways to develop the necessary solution.
In what ways has Aestech prioritised high-quality products and services, and how does the company
ensure that its offerings conform to customer specifications and international standards?
Our products have a number of patents and certificates, including certification confirmations from the ift Rosenheim laboratory. These certifications are recognised by architects, engineers, and developers not only in Europe but also far beyond its borders. However, the best confirmation of the quality and durability of Aestech solutions is our projects. Some of them have been in operation for 17 years, which indicates the highperformance characteristics of our solutions.
In what ways do these frameless glass solutions improve construction time, energy efficiency, and flexibility compared to conventional methods?
Speaking of time, one of the advantages of our technology is that you do not have to wait until the construction process is complete to start the installation. Installation work can begin when at least one floor is ready. As for energy efficiency, it is worth digressing here and telling you more about Aestech Glazing technology, which is based on our patented development - a highstrength double-glazed unit.
Such a double-glazed unit has design features that allow it to withstand a much heavier load. It is also selfsupporting, meaning that it does not require racks or transoms, which are usually made of metal, which is known to be a conductor of both heat and cold.
The contour of our double-glazed windows is reinforced by a frame made of GRP profile, an extremely lightweight yet ultra-strong material with thermal conductivity characteristics similar to wood. Each double-glazed unit is connected to the neighbouring one simply by means of fasteners that are screwed into the frame and then attached to the building’s supporting structures. In addition to energy efficiency, such a façade will look much lighter and at the same time more aesthetically pleasing compared to standard solutions.
The absence of a framework allows us to be as flexible and efficient as possible both in project implementation and in the renovation of old residential or commercial buildings. A simple example: in order to renovate a skyscraper, the building must be shut down and vacated.
This is not profitable for the owners, because they lose their money. For this reason, today we have hundreds of such buildings around the world, especially in the United States.
Thanks to our solutions, the façade renovation in such a building can be carried out on each individual floor, which will not affect the overall functioning of the building. The renovation is carried out gradually, and the owners receive an updated aesthetic and energyefficient building that generates more income, while tenants receive comfortable and aesthetic offices.
As a vivid example of the capabilities of Aestech solutions, I can name one of our favourite projects - an all-glass entrance group of a residential complex in Kyiv, which is made in the form of a 12-meter-high cube. The structure is designed in such a way that even with its proportions, it excludes the use of aluminium holding systems. We wanted to create an object that would impress and
attract the eye and to understand that we succeeded, you just needed to stand next to the building and see how passersby reacted to it.
The second example is not exactly a project, but it also perfectly demonstrates the capabilities of the technology. It is one of the elements of our stand for the World Architecture Festival 2022 - a 3D glass arch. It is a three-dimensional all-glass structure 3.9 meters high. This arch is made of 23 glass units of different shapes and sizes and has a large number of faces, so the structure has a unique look on each side. It perfectly demonstrates the flexibility of our technology.
In a rapidly changing industry, how does Aestech stay ahead of the curve in terms of technology, sustainability, and industry best practices?
We follow the industry, attend the largest specialised events, communicate with engineers and architects, and hold specialised events for local professional communities - this gives us an understanding of trends or the industry’s current needs are.
How do you see the current trends for your products in the façade industry in your region?
The demand for environmental friendliness is still very strong, and our product meets all the current requirements. Glass is an environmentally friendly material, but all-glass structures cannot be called environmentally friendly because of the large amount of metal involved. Firstly, it requires a lot of energy to produce it, and it produces a huge amount of harmful emissions.
Secondly, as I have already mentioned, metal is a conductor of heat and cold, which makes the building’s energy efficiency worse and requires more resources to maintain comfortable indoor conditions. Our solution solves both of these problems and also improves the aesthetics of the building. And this is just a part of the benefits.
What are the major challenges you find in the industry? How do you overcome those?
Paradoxically, the biggest challenge is myths and prejudices about glass. Often the market is simply afraid of new solutions, especially such a conservative one as the construction market.
We have already gone this way in Ukraine, and now we are going through it in other markets. As soon as the client gets acquainted with our solutions and sees all its advantages in concrete examples, he turns into an evangelist for our solutions.
How do you envision the future of architecture being influenced by frameless glass solutions, and what role do you see your company playing in this evolution?
The use of translucent solutions in architecture tends to spread. Thanks to our technologies, the popularity of translucent solutions can increase in those regions where large translucent structures were previously refrained from being used on a massive scale: in cold climate regions, hot climate regions, areas of high seismic activity, etc.
“Decarbonisation is a Multifaceted Challenge and Requires a Mosaic of Solutions”
About the Author
Tushar Sharma is an architect and urban designer with over 12 years of experience. He is a Technical Design Lead at Woods Bagot in the London Studio. Tushar offers a broad range of skills across all project stages, from concept design to construction phases, with extensive knowledge in technical design, construction, and onsite experience. Tushar has worked on multiple award-winning schemes of varying scales and uses, across the UK, India, and the Middle East – where he has just completed the Stage 04 design of a major cultural project. Before joining Woods Bagot, Tushar worked at Pilbrow and Partners Architects for five years and Proctor and Matthews Architects for seven years, where he was a project lead and technical design lead on a number of highly acclaimed projects. Tushar has a keen interest in Modern Methods of Construction and DfMA (Design for Manufacture and Assembly).
• Could you please tell us about your journey in the field of architecture? How did you think of becoming an architect? What do you enjoy most about your profession?
My career in architecture so far has been fulfilling and dynamic. I am from a family of building contractors so, from a very young age, I was drawn to the intersection of creativity, problem-solving, and making. Architecture has provided the perfect outlet for that passion. The idea of shaping spaces and contributing to the built environment always fascinated me.
What I enjoy the most is the opportunity to bring a vision to life, creating something tangible and enduring whilst addressing the functional needs and aspirations of the people who inhabit those spaces. Every project is a unique puzzle and requires a deep understanding of the context – historical, spatial, environmental, social, and economic – as well as collaboration with the community and various other stakeholders. The diversity of these challenges keeps me engaged and motivated.
• What do you think is the role of a façade or building envelope in the sustainability enhancement of a building?
In the face of the climate crisis and the subsequently urgent need for the construction industry to align with sustainability goals, the role of a building envelope is paramount. Its significance is not only vital but evolving rapidly, making the ‘fabric first’ approach crucial in our efforts to reduce carbon emissions and conserve energy.
Decarbonisation is a multifaceted challenge and requires a mosaic of solutions. The building envelope is the first line of defense against external elements and is thus at the forefront of this transformative journey. The ‘fabric first’ approach puts emphasis on optimising the building fabric. This process spans from increased thermal performance and airtightness, carefully assessed solar control and natural ventilation, user comfort, and fenestration orientation to thoughtful material selection such as the use of circular materials. The goal is not only to address operational carbon but also the embodied carbon within the construction materials.
Paper Tile Studies
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Paper Tile Studies
Paper Tile Studies
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Paper Tiles Studies
It has become critical to develop methodologies to assess and quantify the carbon emissionsembodied, operational, and whole-life carbon - on our path to a carbon future by 2050. Technological advancements and analytical tools will play a pivotal role in navigating these complexities by enabling a data-driven analytical approach to inform sustainable building practices.
Please tell us about any interesting ongoing or recently completed projects at Woods Bagot. I am particularly fascinated by The Londoner Hotel project, especially its façade composition. The hotel ingeniously slots into a dense and bustling urban setting, leveraging the site potential both above and below ground, to deliver significant value to the community.
Notably, the project boasts a BREEAM Excellent rating and features one of the world’s deepest ‘habitable’ basements that accommodates two cinema screens, as well as various hotel amenities and staff spaces.
Interestingly, as part of the planning consent requirements, the project was required to contribute to the local community in some form of public artwork. Rather than treating this as a mere add-on, our approach involved working in collaboration with locally based artist Ian Monroe. Together, we conceptualised and integrated a captivating public artwork into the building’s fabric which resulted in a dynamic undulated royal blue terracotta façade to the tower, positioned to mark the entrance to the building and the alternating patterns of glazed tiles activating the window reveals that enhances the overall aesthetics thus delivering a layered public realm experience.
Composed of 15,000 bespoke individually handmade tiles, the façade serves as a homage to the area’s tilemaking history. The material palate is contextual, nodding to the numerous glazed brick insertions that characterize public buildings in the area.
To overcome the challenge of executing the complex façade composition, The Londoner required extensive coordination between our extremely talented in-house digital design specialists, the project engineers Arup, consultants, and off-site fabricators.
Paper Tile Studies
The process began with Monroe’s hand-drawn sketches and papercut models, experimenting with colours, shapes, and arrangements. Using digital design tools, we optimised the geometry of the tiles - size, weight, and thickness, and coordinated the metal subframe design, and the mechanical elements, without compromising the design intent.
Paper Tile Studies
Paper Tile Studies
Paper Tile Studies
The Londoner is an artistic triumph that features incredible craftsmanship that extends from its ground floor to its roof. Intricate and complex, this level of artistry would be challenging to achieve manually and so was made visible and tangible through collaboration amplified by digital tools – making it a technological feat too.
Project Details:
• Project Name: The Londoner
• Location: London
• Client: The Edwardian Group
• Architect: Woods Bagot
• Engineering: Arup
• Faience manufacturer: Darwen Terracotta and Faience
• Materials used for façade & and fenestration: Portland Stone, Faience, Aluminum
• How has the integration of Building Information Modeling (BIM) impacted the process of façade design in building projects, and what key advantages or challenges have emerged as a result?
Building Information Modeling (BIM) and advanced computational analytical methods have significantly transformed the process of façade design in building projects. BIM has provided a holistic and collaborative platform that enhances communication and coordination amongst the design team subcontractors
The Londoner : Section
and various other stakeholders involved in the design and construction process. BIM has presented the scope for reasoned decision-making, increased efficiency and accuracy, and has facilitated Design for Manufacture and Assembly (DfMA) in the design and delivery process.
A comprehensive three-dimensional digital model allows a more accurate representation of the façade’s intricacies, enabling better visualisation and understanding of the design and components, material performance and optimisation, clash detection and coordination, construction tolerances and sequencing,
and enhanced construction process - thus considerably reducing the margin for errors.
Nevertheless, the BIM process presents several challenges. These include legal, contractual, and data security concerns, along with time and cost investment relative to the project scale, as well as competency and training requirements. One common challenge we frequently encounter is the interoperability between softwares used by different stakeholders. To mitigate this, we emphasise clear communication and ascertain early agreements on standards and processes through the BIM Execution Plan (BEP). However, there are always lessons to be learned, particularly in managing extremely complex geometries carrying complex data within the BIM environment, which can potentially impact productivity. The most important thing is to communicate clearly, early and continually.
• As technology continues to advance, what emerging trends or innovations do you foresee in the intersection of BIM and façade design, and how might these developments influence the future of building design and construction?
Building Information Modeling (BIM) in façade design holds exciting prospects for the future of building design and construction, ranging from enhanced
visualisation and construction methodologies to the integration of cutting-edge technologies and cloudbased workflow.
As technology continues to advance, several emerging trends and innovations are likely to shape this intersection. With the ongoing shift towards sustainability and circular economy, smart façades, advanced simulation and analytical methods, supply chain integration, advancement in DfMA, and Modular construction techniques for high-performing façades, BIM can play a pivotal role in the seamless integration
of these interventions. These trends and innovations will not only streamline the design and construction process but also contribute to the creation of more empathetic, user-centric, sustainable, efficient, and visually striking buildings.
• What is your vision for 2030? What kind of cities would you like to see?
To answer a complicated question as simply as possible, my vision revolves around placing people at the heart of urban developments. In envisioning cities for 2030, I see a profound shift towards people-centric design interventions. I imagine cities where every aspect of urban design is guided by a deep understanding of community needs and aspirations. This entails reimagining urban spaces as places that prioritise
wellbeing of people, emphasising health, happiness, and interconnectedness of communities- with easily accessible and inclusive amenities, green spaces and cultural hubs that foster a sense of belonging.
• One piece of advice you would like to give to aspiring architects?
To embrace a mindset of continuous learning and curiosity and take every opportunity to expand your knowledge – whether through formal education or hands-on experience. In this ever-changing landscape, a commitment to learning not only enhances your professional growth but also empowers you to contribute meaningfully to the transformative and creative process of shaping the built environment sustainably.
BIG – a global architectural firm has revealed plans for Freedom Plaza, an ambitious project poised to redefine Manhattan’s iconic skyline. Situated in the vibrant Midtown East neighborhood, this four-tower development promises to be a beacon of innovation and architectural excellence.
Freedom Plaza, spanning a sprawling 6.7-acre site opposite the renowned United Nations Headquarters complex, will feature a striking ensemble of residential and hotel skyscrapers interconnected by a twisting skybridge. Designed to offer a harmonious blend of functionality and aesthetic appeal, the project aims to pay homage to the city’s rich architectural heritage while introducing playful
and sculptural elements along the waterfront.
At its core, the development boasts a central park designed by US studio OJB Landscape Architecture, accentuated by the spiral-shaped Museum of Freedom and Democracy. Rising to tower heights of 615 feet, the hotel towers will feature a multi-story cantilevered skybridge, adding a dynamic dimension to the urban landscape. Within the hotel
towers, luxury accommodations including the prestigious Banyan Tree and Mohegan hotels will be complemented by a cutting-edge conference and entertainment center, complete with an underground gaming area for guests’ enjoyment.
On the residential front, two towering structures reaching heights of 550 and 650 feet will offer a total of 1,325 apartments, with a significant portion dedicated to affordable housing initiatives. Drawing inspiration from the city’s modernist architecture of the 1950s and 60s, these towers will showcase striped glass and aluminum façades, marrying tradition with contemporary design elements.
Atelier Alter Architects has recently unveiled their latest masterpiece: the Ruian Qiaomao Tower, a stunning 45,000 square meter office tower located in the heart of Beijing. Inspired by the dynamic energy of the bustling city and the cutting-edge innovation of Ruian, a renowned manufacturer of electric vehicle components, this architectural marvel embodies the essence of speed and future.
The tower’s design, characterised by its ribbon-like concave mirror façade, is a testament to the forward momentum of both Beijing and Ruian. Massive, powerful lines sweep from the city to the building, imbuing it with a sense of strength and vitality. The reflective surfaces add a futuristic flair, creating a visually captivating aesthetic that captivates onlookers.
But the Ruian Qiaomao Tower is more than just a striking visual landmark – it is a harmonious blend of urban functionality and architectural ingenuity. Divided into three parts - the ground city square, podium, and tower - the tower seamlessly integrates commercial spaces, an auditorium, and office spaces,
fostering interconnections between urban, building, interior, and people at different scales. A large, ribbon-like concave form serves as the unifying element, traversing the three parts of the tower and linking space from the city’s entrance square to the podium façade and the tower’s office interiors. This cohesive design not only enhances the building’s aesthetic appeal but also reinforces its urban attributes on both a material and abstract level.
With its surreal integration of cityscape and architectural form, the Ruian Qiaomao Tower stands as a symbol of innovation and progress - a beacon of inspiration for the future of urban design and development.
In a significant architectural feat, JSWD has unveiled the Neuer Kanzlerplatz office complex in Bonn, Germany. Situated at a pivotal junction where the southern city center meets the former government district and the renowned “Museum Mile,” this striking addition enhances Bonn’s urban landscape.
The complex seamlessly integrates with the existing high-rise ensemble, including the iconic Posttower by Helmut Jahn and the historic “Langer Eugen” once housing the German Parliament, along with other UN buildings at Bundeskanzlerplatz.
JSWD’s design ethos manifests in a cohesive façade structure across the three buildings, creating a visually unified entity.
Central to the design is a slender vertical tower that rises majestically from one of the buildings, soaring 28 stories and over 100 vertical meters. This architectural marvel not only anchors the office complex within the city skyline but also serves as a beacon of modernity and innovation. Embracing an irregular layout, the buildings snugly nestle into the corners of the triangular plot, forming an inviting outdoor public
space at the heart of the complex. This space seamlessly connects with the neighboring residential area, fostering community engagement and pedestrian flow. The façade grid of the mid-rise buildings two and three, comprising load-bearing precast concrete elements, ensures column-free office spaces while exuding a timeless aesthetic. Inside, innovative engineering solutions are evident, with triangular fiberglassreinforced concrete elements adorning the ceilings and rear walls.
JSWD’s meticulous attention to detail extends to the exterior façade, crafted from cream-white, acidified architectural concrete with a doublelayer hydrophobic coating, seamlessly transitioning into the interior spaces.
UNStudio has announced the completion of Huawei’s flagship store in Shanghai, a collaboration between the renowned architecture firm and Huawei’s internal design team. This innovative retail space promises an immersive experience, blending elements of nature, technology, and consumer preferences.
Drawing inspiration from biophilic forms, the two-level store seamlessly integrates indoor and outdoor environments, incorporating recycled materials to minimise its environmental impact. The façade, resembling petals in various stages of growth, pays homage to Huawei’s
polar codes technology, forming an integrated geometric system that merges the brand with nature and technology. The transparency of the façade, achieved through oversized petal stems, maximizes natural light and views into the store during the day, while subtle lighting elements emit a soft glow at night.
At the heart of the store lies the ‘Tree of Harmony,’ a spiraling centerpiece that not only facilitates circulation between floors but also offers augmented reality (AR) experiences for visitors, engaging them in a sensory journey of sight, sound, and smell reminiscent of nature.
Warm tones dominate the interior palette, with ivory ceilings and floors complemented by wood and glass fiber-reinforced concrete columns.
This flagship store represents a bold exploration of architectural design, transforming retail space into an interactive environment that reflects Huawei’s ethos of innovation and connectivity.
