Boost building sustainability with strategic glass design

What are the latest trends in glass façade design and glazing technology?

The latest trends in glass façade design and glazing technology represent a combination of aesthetic innovation, performance enhancement, and sustainability. These trends are shaped by advancements in materials science, manufacturing processes, and a growing emphasis on energy efficiency and environmental responsibility. Here’s an in-depth look at some of the most significant trends:

Energy efficiency and sustainability

• Low-E Coatings: Low-emissivity (Low-E) coatings are a critical advancement in the realm of glass technology, specifically designed to minimise the transmission of ultraviolet (UV) and infrared (IR) radiation while allowing maximum visible light to permeate. These coatings effectively enhance the thermal insulation properties of glass, thereby reducing energy consumption for heating and cooling systems. As climate change and energy efficiency become global imperatives, Low-E coatings are increasingly adopted not only in the UK but also in developing and developed countries alike. By enhancing the performance of glazing systems, these coatings contribute to lower operational costs and improved comfort for occupants, aligning with international sustainability goals.
• Double and Triple Glazing: The implementation of Insulating Glass Units (IGUs) featuring double or triple glazing has emerged as a standard practice in modern façade design across various regions. These units consist of two or three layers of glass, typically filled with inert gases such as argon or krypton, which significantly enhance thermal performance and sound insulation. In countries with diverse climatic conditions, double and triple glazing plays a vital role in reducing heat loss in colder climates and minimising heat gain in warmer regions. This adaptability not only meets local building codes but also supports the global movement towards energy-efficient architecture, ensuring occupant comfort and sustainability.
• Photovoltaic Glazing: Integrating photovoltaic cells into glass façades represents a revolutionary approach to sustainable building design, allowing structures to generate their electricity from solar energy. This technology is instrumental in the development of net-zero energy buildings, which strive to balance energy consumption with energy production. In both developed nations and emerging markets, the push for renewable energy solutions is driving the adoption of photovoltaic glazing. This innovation not only enhances the energy profile of buildings but also promotes energy independence and resilience, aligning with global efforts to combat climate change.

 Advanced manufacturing techniques

• Float Glass Process: The float glass process, a foundational technique in glass production, involves floating molten glass on a molten tin bed to achieve uniform thickness and smooth surfaces. This method has seen significant advancements, improving the scalability and efficiency of glass manufacturing. As the demand for large-format glass panels grows globally, including in both developed and developing countries, the float glass process plays a pivotal role in meeting architectural requirements while ensuring high-quality outputs. Innovations within this process also focus on reducing waste and energy consumption, aligning with sustainability objectives.
• Curved and Bent Glass: Recent advancements in manufacturing technologies have enabled the production of complex shapes and curves in glass, allowing architects to create fluid and organic building façades. This capability caters to a global demand for innovative design solutions that enhance both aesthetics and functionality. In markets worldwide, from the bustling cities of Europe to rapidly developing urban centers in Asia, the use of curved glass is becoming increasingly popular, offering architects the flexibility to push design boundaries while delivering buildings that resonate with their environments.
• Digital Printing and Ceramic Fritting: Digital printing and ceramic fritting techniques allow for the application of custom patterns and images onto glass surfaces, providing a unique blend of functional and decorative benefits. These methods enable architects and designers to incorporate branding, shading solutions, and artistic expressions directly into the façade. As the global façade industry embraces the trend toward bespoke designs, these techniques offer a versatile solution that enhances the visual appeal of buildings, catering to diverse cultural contexts and aesthetic preferences.

Smart glass technologies

• Electrochromic Glass: Electrochromic glass represents a groundbreaking advancement in smart glazing technology, capable of dynamically changing its tint in response to electrical stimuli. Recent enhancements in this technology have significantly improved transition speeds, durability, and overall energy efficiency, making it a viable option for large-scale applications. As countries across the globe seek to implement smart building technologies, electrochromic glass offers a sophisticated solution for managing solar gain and enhancing occupant comfort, thus addressing the growing demand for energy-efficient building solutions.
• Thermochromic Glass: Thermochromic glass changes its tint based on ambient temperature fluctuations, providing an intelligent response to varying environmental conditions. Innovations in this technology have improved its effectiveness in managing solar gain, reducing the necessity for supplementary shading devices. As awareness of climate change and energy conservation rises globally, thermochromic glass serves as an effective tool for optimising energy use in building designs across diverse climates and regions.
• Photochromic Glass: Photochromic glass darkens upon exposure to sunlight, offering a passive method for managing light levels within spaces. Recent advancements have enhanced its responsiveness and durability, making it a practical choice for various applications. Globally, as the focus shifts towards creating adaptive environments that enhance occupant comfort, photochromic glass is gaining popularity as a valuable component in modern façades.
• Suspended Particle Devices (SPD): Suspended Particle Devices (SPD) technology allows for rapid transitions between transparent and opaque states, providing flexible light management solutions. Ongoing advancements aim to improve clarity, colour consistency, and energy consumption, making SPD technology increasingly appealing across international markets. As the demand for adaptable building solutions rises, SPD technology positions itself as a key player in optimising energy performance and occupant comfort.
• Liquid Crystal Devices (LCD): Liquid Crystal Devices (LCD) offer the ability to switch from transparent to opaque, providing privacy on demand. New developments in this area are enhancing durability and reducing costs, making them more accessible for various applications across different markets. As urban environments become denser and privacy concerns increase, the integration of LCD technology in façades is expected to grow, catering to a global audience seeking innovative design solutions.

Enhanced safety and security

• Laminated and Toughened Glass: Laminated and toughened glass are essential materials for enhancing the safety and security of building façades worldwide. Laminated glass consists of layers of glass bonded with a resilient interlayer, ensuring that it remains intact upon impact. Toughened glass undergoes heat treatment to increase its strength and shatters into small, less hazardous pieces. Given the increasing emphasis on occupant safety and security in various countries, the use of these advanced glazing solutions is becoming standard practice, particularly in high-traffic urban areas.
• Blast-Resistant and Bulletproof Glass: In response to escalating security concerns globally, the trend towards incorporating blast-resistant and bulletproof glass in building façades is gaining momentum, particularly in high-risk regions. These materials are specifically designed to withstand significant impacts and explosions, providing critical protection for both occupants and property. As security needs evolve, the adoption of such glazing solutions is expected to rise, catering to both developed and developing markets that prioritise safety. Acoustic Insulation

Acoustic laminated glass:

Acoustic laminated glass features an acoustic interlayer designed to significantly reduce sound transmission, making it ideal for buildings situated in noisy urban environments. Enhanced acoustic performance is increasingly recognised as vital for occupant comfort and productivity. In both developed and developing countries, where urbanisation is rapidly increasing, the demand for effective acoustic solutions is on the rise, making acoustic laminated glass a popular choice for modern construction projects.

Transparency and natural light

• Maximising Daylighting: Modern glazing technologies aim to maximise natural light while minimising glare and thermal gain. This includes the use of expansive, uninterrupted glass panes alongside advanced shading devices. Across the globe, the emphasis on natural light in architectural design is increasingly recognised for its positive impact on occupant well-being. As a result, architects are integrating these technologies into their designs to create brighter, more inviting spaces that cater to diverse cultural and climatic contexts.
• Transparent Insulation Materials (TIMs): Transparent Insulation Materials (TIMs) provide excellent thermal insulation while allowing natural light to penetrate interior spaces. This innovation facilitates well-lit environments without compromising energy efficiency. As global building codes increasingly prioritise sustainability, TIMs have emerged as a viable solution for architects seeking to enhance building performance across varying climates and regulatory frameworks.

Environmental impact and lifecycle assessment

• Embodied Carbon Reduction: The focus on reducing embodied carbon in glass production is gaining momentum across the global façade industry. This involves optimising manufacturing processes, utilising recycled materials (cullet), and enhancing energy efficiency in production facilities. As countries strive to meet international climate agreements, prioritising sustainability in glass production is becoming paramount, offering a pathway to reduce carbon footprints while promoting eco-friendly practices.
• End-of-Life Recycling: Initiatives to improve the recyclability of glass façades at the end of their lifecycle are gaining traction internationally. This includes developing innovative technologies for the efficient separation and recycling of laminated glass and other composite materials. As the global construction industry moves toward circular economy principles, the ability to recycle building materials effectively is becoming a key consideration, enhancing sustainability across various markets.

Integration with building systems

• Building Integrated Photovoltaics (BIPV): Building Integrated Photovoltaics (BIPV) systems represent a seamless integration of photovoltaic panels into the building envelope, combining energy generation with aesthetic and functional elements of the façade. This technology is gaining traction globally as architects strive to achieve sustainability goals without compromising design integrity. BIPV systems not only promote renewable energy but also align with international efforts to reduce dependence on fossil fuels.
• Smart Façade Systems: Smart façade systems incorporate sensors and automation to adjust shading, ventilation, and lighting based on real-time environmental conditions. This technology optimises energy usage, enhances occupant comfort, and contributes to the overall efficiency of buildings. As the demand for smart building solutions rises, these systems are being increasingly adopted in both developed and developing countries, reflecting a global trend towards more sustainable and responsive architectural practices.

How do modern glass façades contribute to the energy efficiency of a building, and what innovations have made the most impact in this area?

Modern glass façades contribute significantly to the energy efficiency of buildings through a variety of advanced materials, coatings, and design techniques that optimize thermal performance, control solar gain, and enhance natural lighting. Here’s an in-depth look at how these façades achieve these goals and the innovations that have made the most impact:

Thermal performance

• Insulating Glass Units (IGUs): Insulating Glass Units (IGUs) are critical to achieving high thermal performance in modern façades. Comprising multiple panes of glass sealed around the edges, IGUs create an effective barrier against heat transfer. The introduction of advanced spacer technologies, such as warm-edge spacers, not only reduces thermal bridging but also enhances the overall energy efficiency of the unit. These innovations are increasingly vital in diverse climates, from the cold winters of Northern Europe to the hot, humid conditions of tropical regions. Moreover, the market is witnessing a shift towards integrated solutions that combine IGUs with other building envelope technologies, ensuring a holistic approach to energy efficiency.
• Low-emissivity (Low-E) Coatings: Low-E coatings have evolved beyond standard applications to include multiple types that cater to specific climatic conditions and building orientations. For instance, selective Low-E coatings can be tailored to reflect specific wavelengths of infrared radiation, providing optimal thermal performance for various applications. The use of these advanced coatings is becoming increasingly prevalent globally, as architects and builders seek to meet both regulatory standards and the growing demand for energy-efficient buildings. Additionally, the application of Low-E coatings is now being considered in retrofitting projects, where existing windows can be upgraded to improve thermal performance without the need for complete replacements.
• Triple Glazing: As energy efficiency becomes a global priority, triple glazing is gaining traction in regions where thermal insulation is critical. Not only does triple glazing provide superior thermal performance, but it also contributes to enhanced acoustic insulation, making it particularly appealing in urban environments where noise pollution is a concern. The incorporation of advanced manufacturing techniques has led to lighter and thinner triple-glazed units, making them applicable to a wider range of architectural designs without compromising structural integrity. This trend is echoed in various markets worldwide, as builders and developers increasingly recognise the long-term benefits of investing in higher-performance glazing systems.

Solar control

• Spectrally Selective Glazing: Spectrally selective glazing continues to evolve with advancements in coating technologies, allowing for even greater control over solar heat gain without sacrificing natural light. This innovation is particularly advantageous in regions with high solar exposure, as it effectively reduces the reliance on mechanical cooling systems. The ability to customise the spectral properties of glazing also enables architects to create more energy-efficient buildings that are aesthetically pleasing and functionally superior. This has led to a growing demand for spectrally selective glazing not just in developed countries, but also in emerging markets, where energy efficiency is becoming a key consideration in new constructions.
• Solar Control Glass: The development of solar control glass has diversified significantly, offering a wide range of options including tinted, reflective, and even hybrid varieties that combine multiple properties. These solutions can be tailored to meet the specific needs of different climates, ensuring that buildings remain comfortable year-round while minimising energy consumption. The rising awareness of the benefits of solar control glass is evident globally, as both residential and commercial projects seek to integrate these advanced materials into their designs to enhance occupant comfort and reduce energy costs.

Natural lighting and daylighting

• High-Transparency Glass: The latest advancements in high-transparency glass technology have resulted in products that not only maximise daylight penetration but also offer enhanced thermal performance. These innovations often involve the use of advanced coatings and processing techniques that ensure minimal interference with visible light while effectively managing solar gain. The trend towards greater use of high-transparency glass is evident in contemporary architectural practices worldwide, as designers aim to create bright, inviting interiors that reduce reliance on artificial lighting. This is particularly relevant in regions where natural light is scarce during certain seasons, allowing for improved quality of life in residential and commercial spaces alike.
• Light-Diffusing Glass: Light-diffusing glass has gained prominence as a versatile solution for achieving ambient lighting in spaces where privacy is a concern. The use of innovative materials, such as translucent insulation materials (TIMs), allows for effective light diffusion without compromising thermal insulation properties. This technology is becoming increasingly popular in both public and private buildings worldwide, particularly in urban settings where noise and visual privacy are paramount. The ability to blend aesthetic qualities with functional benefits positions light-diffusing glass as an essential component in modern façade design.

Innovations in glass façades

• Dynamic Glazing Technologies: Dynamic glazing technologies are at the forefront of innovation in façade design, enabling real-time adaptations to changing environmental conditions. The ongoing development of these technologies – such as advanced electrochromic and thermochromic systems—has made them more responsive, reliable, and accessible for various applications. As building owners and developers seek to enhance energy efficiency and occupant comfort, dynamic glazing is being increasingly integrated into both new constructions and retrofit projects across the globe, facilitating a more sustainable approach to building design.
• Double-Skin Façades: Double-skin façades are being embraced not just for their aesthetic appeal but also for their functional benefits in improving energy efficiency and indoor air quality. Advances in design and engineering allow for more sophisticated ventilation systems that can be naturally or mechanically controlled, promoting energy savings while enhancing occupant comfort. These façades are particularly beneficial in high-rise buildings, where they can act as a thermal buffer, reducing the impact of external weather conditions. The growing adoption of double-skin façades in various global markets reflects a commitment to sustainable architecture and energy-efficient design.
• Building Integrated Photovoltaics (BIPV): Building Integrated Photovoltaics (BIPV) are increasingly viewed as a dual-purpose solution that marries energy generation with architectural aesthetics. The integration of photovoltaic cells into glass façades not only offsets energy consumption but also contributes to the overall sustainability of the structure. As the market for renewable energy solutions expands globally, BIPV is gaining traction in both commercial and residential projects. This trend is particularly promising in developing countries, where the need for sustainable energy solutions is urgent and the potential for solar energy is significant.

Operational efficiency

• Automated Shading Systems: Automated shading systems are becoming an integral part of modern façade design, particularly in response to the growing need for energy efficiency and occupant comfort. These systems use advanced sensors and controls to adjust shading based on real-time data, such as sunlight intensity and building occupancy. This level of automation not only optimises natural light but also significantly reduces energy costs associated with artificial lighting and cooling. The adoption of automated shading systems is increasingly seen in various markets, reflecting a global trend towards smarter, more responsive building technologies.
• Ventilated Façades: Ventilated façades have gained recognition for their ability to improve thermal performance through enhanced air circulation. By allowing for the natural movement of air between layers of glass, these systems provide a passive cooling effect that can reduce reliance on mechanical heating and cooling. This approach is particularly valuable in hot climates, where maintaining comfortable indoor temperatures is crucial. The growing enthusiasm for ventilated façades is evident in both developed and developing countries, as they offer an effective solution to energy efficiency while promoting a healthier indoor environment.

Advanced coatings and films

• Thermal Insulating Films: Thermal insulating films present a cost-effective option for enhancing the energy efficiency of existing buildings. These films can be applied to windows to improve thermal performance without requiring extensive renovations. This technology is especially advantageous in developing countries, where retrofitting existing structures can significantly contribute to energy savings and sustainability goals. As awareness of energy efficiency grows, the demand for thermal insulating films is expected to rise, presenting an opportunity for innovation in the façade industry.
• Hydrophilic and Hydrophobic Coatings: The application of hydrophilic and hydrophobic coatings in façade design is becoming increasingly popular due to their ability to simplify maintenance and enhance the longevity of glass surfaces. These coatings offer self-cleaning properties that can significantly reduce the frequency and cost of cleaning, making them particularly valuable in urban environments where pollution can adversely affect the appearance of buildings. The global adoption of these advanced coatings reflects a commitment to sustainability and resource efficiency, promoting buildings that maintain their aesthetic appeal with minimal environmental impact.

Impacts and considerations

• Energy Savings: The strategic design and implementation of glass façades can lead to substantial energy savings, making them a critical component in achieving low operational carbon buildings. By minimising energy consumption for heating, cooling, and lighting, well-designed façades not only enhance the financial viability of projects but also contribute to broader sustainability goals. As energy efficiency standards become more stringent across the globe, the role of glass façades in reducing operational energy use is increasingly recognised as vital by architects, builders, and policymakers alike.
• Comfort and Health: The influence of modern glass façades on indoor environmental quality is profound, with studies linking improved thermal comfort, reduced glare, and increased natural light to enhanced occupant health and productivity. As the focus on wellness in building design continues to grow, architects are increasingly prioritising the integration of effective glazing solutions that create healthier indoor environments. This shift is not limited to developed nations; emerging markets are also beginning to recognise the importance of occupant well-being in the design of residential and commercial spaces.
• Sustainability: The continuous evolution of glass façade technology plays a crucial role in advancing sustainability in the built environment. By integrating energy-efficient solutions and reducing greenhouse gas emissions, modern glazing technologies can significantly lower the overall carbon footprint of buildings. As countries around the world strive to meet international climate commitments, the role of glass façades in promoting sustainable architecture becomes increasingly vital. The adoption of innovative glazing solutions is not just a trend; it represents a fundamental shift towards more responsible and resilient building practices on a global scale.

What are the key factors to consider for ensuring the safety and durability of glass façades in various climates?

Ensuring the safety and durability of glass façades in various climates involves addressing several critical factors. These factors can be broadly categorized into design considerations, material selection, installation practices, and maintenance procedures. Here is an in-depth discussion from a safety perspective:

Design considerations

• Wind and Snow Loads Guidance and Standards: The design of glass façades must adhere to local regulations and guidelines, such as the British Standards BS 6262 and BS 5516, which outline the requirements for wind and snow load resistance. These standards provide essential design charts that aid engineers in calculating the appropriate thickness and configuration of glass panels to ensure structural integrity under varying environmental conditions. In developing regions, where building codes may be less stringent, it becomes vital to adopt these standards to enhance safety and resilience.
• Risk of Breakage: In geographic areas prone to high winds or heavy snowfall, the selection of glass must account for these potential stresses. The design should also incorporate features that mitigate the risk of breakage due to debris impacts during storms. This includes the use of impact-resistant glass or protective systems that can absorb and dissipate energy from such forces, thereby improving the overall safety of the façade.

Thermal stress

• Thermal Expansion and Contraction: The impact of climate on glass performance cannot be overstated. In regions with significant temperature variations, the material undergoes thermal expansion and contraction, potentially leading to stress fractures. It is essential to employ design strategies that accommodate these movements, such as using flexible framing systems or expansion joints that allow for natural adjustments without compromising structural integrity.
• Thermal Fracture Resistance: Selecting the appropriate type of glass is crucial in mitigating thermal fracture risks. Advanced glass formulations, including those with enhanced thermal resistance, can withstand rapid temperature changes. Additionally, incorporating design features that facilitate gradual temperature transitions, such as shading devices or thermal breaks, can further reduce the likelihood of thermal stress-related failures. Installation Practices

Proper mounting and support

• Support Mechanisms: The selection of appropriate support systems is critical for ensuring that glass panels remain securely in place. This is particularly crucial for overhead glazing and installations in high-risk areas. Utilizing advanced anchoring techniques and ensuring compliance with structural engineering principles can enhance the safety and durability of the façade.
• Seals and Joints: Effective sealing and jointing methods play a vital role in preventing water ingress, which can compromise the structural integrity of the glass and its supporting framework over time. The use of high-performance sealants and careful attention to detail during installation are necessary to ensure long-lasting performance.

Handling and transportation

• Safe Handling Procedures: The handling and transportation of large glass panes require strict adherence to safety protocols. Implementing proper lifting methods and using protective equipment can prevent pre-installation damage. Training personnel in safe handling techniques is essential, particularly in regions where the risk of accidents is heightened.
• On-Site Safety: To minimise risks during installation, robust safety protocols should be established. This includes ensuring that all personnel are trained and equipped to manage the specific challenges of working with glass. Regular safety audits and adherence to best practices can significantly reduce the likelihood of accidents.

Maintenance and monitoring

• Regular Inspections Routine Checks: Conducting regular inspections of glass façades is essential for identifying signs of stress, cracks, or other damage. This proactive approach allows for early intervention and is particularly important in climates that experience severe weather conditions. Implementing a systematic inspection schedule can enhance the longevity of the façade.
• Post-Breakage Behaviour: Understanding how glass behaves after a breakage event is critical for planning effective maintenance and emergency responses. This knowledge can inform the design of safety protocols and the selection of materials that enhance overall safety.

Cleaning and repairs

• Safe Access for Cleaning: Providing safe access for cleaning and maintenance is imperative to prevent accidents. This includes the installation of suitable access equipment and ensuring that personnel are adequately trained in working at heights. Regular maintenance not only preserves the aesthetic quality of the façade but also contributes to its overall performance.
• Prompt Repairs: Timely repairs or replacements of damaged glass are crucial for maintaining façade integrity and safety. Establishing a responsive maintenance protocol ensures that any
• Issues are addressed swiftly, reducing the risk of further damage and enhancing the safety of the building.

Environmental considerations

• Humidity and Corrosion: In humid or coastal climates, the supporting framework and any metal fixtures must be resistant to corrosion. Selecting appropriate materials, such as stainless steel or specially coated metals, can prevent structural failures and extend the lifespan of the façade. Proper drainage systems and ventilation can also mitigate humidity-related issues.
• UV Exposure: In regions with high UV exposure, selecting glass with UV-resistant properties is essential to prevent degradation over time. This consideration is particularly vital in tropical and equatorial climates, where long-term exposure can compromise the integrity and appearance of the façade.

Testing and certification

• Regulatory Compliance: Ensuring compliance with local and international safety standards is crucial for the performance and safety of glass façades. Regular audits and assessments can help verify that materials and installation methods meet required specifications, fostering confidence among builders, architects, and end-users.
• Post-Failure Testing: Conducting tests to evaluate the post-failure behaviour of glass installations is particularly important in high-risk areas, such as those with overhead glazing.
• Understanding how glass reacts under stress can inform better design practices and enhance overall safety.

Glass risk assessment

CIRIA’s Guidance on glazing at height was published in 2005 with the intention of providing authoritative guidance on the use of glazing at height and its post-breakage behaviour. Whilst Building Regulations, British and International Standards and Codes of Practice try to provide guidance on the specification of suitable glazing, there are some elements that are not appropriately considered or covered, the post-breakage behaviour of the glass being the most important of them. Post-breakage refers to the breakage pattern and retention of the broken glass within the framing member post-breakage. A glass risk assessment should be carried out for the different glazing types to determine the appropriateness and acceptability of the glass type proposed at a given location. CIRIA C632, the guidance on glazing at height, specifically addresses the risks associated with the glass breaking and falling from the building during its service life. It categorizes the risk posed by a certain glazing composition and provides a risk tolerability index for further consideration.

• Most Typical Glazing Types: Depending on design, location of the glazing and the loads it is subjected to, the appropriate glazing could be either of the following types.

1. Annealed Glass: Normal float glass that has not gone through a heat treatment process.
2. Heat-strengthened glass: This heat-treated glass is produced by heating annealed glass and cooling at a controlled speed.
3. Toughened glass: Toughened safety glass (also known as tempered glass) is produced by heating annealed glass and cooling it rapidly also called the quenching process.
4. Laminated glass: Laminated glass comprises 2 or more pieces of glass combined with an interlayer. The plies of glass used can either be of the same or different types of glass.

• Causes of Glass Fracture: Typical reasons for glass fractures in glazed façades are as below:

1. Accidental damage including bird strikes.
2. Cleaning and Maintenance o Environmental loads (Winds and temperature)
3. Vandalism o Nickel Sulphide Inclusions (Toughened)
4. Personal Impact
5. Building movements o Glass defects – Edge chipping, cracks o Exceedance of glass characteristic strength

• Post-Breakage Behaviour of Glazing on buildings: To understand the risks associated with glazing, the post-breakage behaviour of different glazing types should be considered, as described below:

1. Monolithic annealed glass – Monolithic pane of glass within an IGU (insulated glazing unit) or single glazing, breaks into large, sharp shards, with no mechanism for retention within the frame.
2. Monolithic heat-strengthened glass- A monolithic pane of glass within an IGU (insulated glazing unit) or single glazing, breaks into relatively large, sharp shards similar to annealed glass with no mechanism for retention within the frame.
3. Monolithic toughened glass – A monolithic pane of glass within an IGU (insulated glazing unit) or single glazing, breaks into small dice that have the potential to interlock and will fall as a mixture of individual dice and clumps, from a few grams up to approximately 2 kilograms.
4. Laminated glass – will remain in one piece, if breakage occurs, however, If annealed or heat- strengthened glass components are present within the build-up, there may be exposed sharp edges, which could still cause some form of injury, unless retained within a frame. The glazing may fold, if two panes of toughened glass are used and both panels break, due to the wet blanket effect.

• Nature of Risks: Glazing presents a series of risks where post-breakage occurs. These risks include:

1. Safety risks to people both within or around a building during installation, building operation, cleaning/maintenance, and repair.
2. Building performance risks, during building operation. (Thermal, Acoustic)
3. Financial risks at any stage of the whole building life cycle.

• Financial Risk: For the purpose of this note, we are going to discuss financial risks a bit further. Financial risks may arise from a variety of sources, which include:

1. Loss in building value if the installed glass is determined to pose a safety risk generally or does not meet designed performance.
2. Claims for injury.
3. The installed glass requiring replacement as a result of non-compliance with Building Regulations, non-performance, or breakage attributable to inappropriate selection.
4. Increased costs of replacement in the event of failure if the architectural design requires the use of large panes at height, necessitating the use of craneage or other complex materials handling techniques increasing the cost of remedial works. o Potential costs from disruption to the building user if remediation is required after construction.

The cost of remedial works usually falls on a specialist sub-contractor and that has been the usual way of business, however, glazing at height is rarely installed in isolation and the need for remedial work may arise because of improper due diligence by other parties or the failure to comprehend the risks associated with glazing or inadvertently absorbing the risk. In such cases, the cost of remedial works would fall on parties other than the specialist sub-contractor, including other sub-contractors, the main contractor, the designer, or even the client. It should be remembered that there will inevitably be consequential costs, predominantly the fees of lawyers, consultants, test houses, and the like.

The financial cost of loss of public confidence in a building is difficult to establish. Lack of public confidence holds distinct significance for buildings that the public visits as customers and clients should be aware that the public will avoid using their buildings, even temporarily, should there be adverse publicity generated, especially in case of severe injury by falling glass.

• Evaluation of Risks: When evaluating the risk, it is essential to be mindful of the fact that the perception of risk depends on when the assessment is made. Before an accident, people tend to evaluate the risk as lower than if they are assessing the risk retrospectively. Thus, while undertaking a glass risk assessment it is essential that extra care is taken not to be unjustifiably optimistic.

1. One of the most common means of risk assessment is to use a hazard-risk approach, which involves the identification of the following:
2. Identification of hazards. o Likelihood of each hazard occurring.
3. Likelihood of harm resulting from the hazard.
4. Severity of harm. o Situations requiring testing to assess breakage characteristics and evaluate the severity of harm.

The Health and Safety at Work Act 1974 states that all reasonably practicable steps should be taken to reduce risks to people who work, use, or are otherwise present in or around a building. This means that any steps to reduce risks that have a relatively low cost should be carried out. However, risk assessment provides all parties involved with a clear understanding of the risk and the opportunity to reduce or mitigate the risk entirely.

Risk Minimisation and Control – Retro Measures: Where a significant risk has been identified on an existing building, consideration should be given to means of reducing it. Some of the measures are listed below:

• Restricting access to the space below the glazing, by installing gardens, sculptures, or similar features
• Replacing glazing with safer glass or non-glass alternatives
• Applying a film to the glass to change post-breakage behaviour.
• Installing netting, screens, or staging to catch falling glass.
• Installing appendages, such as brise soleil, to break up and slow down the fall of the glass.
• Providing a barrier in front of the glazing to reduce the likelihood of impact.
• Adding manifestation to reduce the likelihood of impact.

However, the most expensive option would likely be to change the glazing completely, which needs a thorough review of all the implications that follow, and all parties involved.

Glass risk assessment as per CIRIA provides a comprehensive risk rating for the glazing on a building, however, we recommend Clients discuss all their building requirements internally within their organisation, with the designer and contractor, if it’s a new build and a façade consultant or a glass specialist in all cases to ensure, the risks are identified and they have followed the hierarchy of ERIC (Eliminate, Reduce, Inform and Control), and any remaining residual risks are recorded and informed to the ultimate client/building owner, making it clear the risks associated with the building and the additional responsibilities that need to be absorbed due to the actual and residual risks involved.

This helps reduce the potential for disputes and legal action caused by inappropriate decisions being made or through a client’s expectation not being met, and where completed, shows a competent level of due diligence, should breakage occur at a later date.

Conclusion

Rather than being simply an architectural garnish, glass façades have evolved to be an efficient and comfortable system that plays a major role in energy management, comfort, and resilience of occupants and buildings. The industry insights highlight how the recently popular modifications and developments in glass façade design and technology are not only for beautification purposes; it is to harmonise the man-made structures and the natural habitats.

One common theme that emerged from our interviews is the tremendous potential of glass in enhancing energy performance. From energy-efficient glazing systems that control solar heat gain and enhance R-value to the advent of electronically and thermally controlled glass, such façades play a vital role in reducing the total energy usage of the building.

Opaque smart glass, especially, takes energy efficiency to a new level by implementing conventional operable louvers and modulating the amount of light and heat the building receives based on the exterior conditions.

As soon as it becomes clear that climate change is a given rather than a prediction, glass façades have to be designed for extreme as well as normal conditions without compromising on sturdiness. The importance of using the right kinds of glass, coatings, and support structures suitable for the weather and utilization areas in ensuring the durability of the façade was highlighted by the experts.

Furthermore, the use of glass façade systems in sustainable building and certification processes such as LEED indicates a rise in green architecture. The operative nature of glass is that it can not only help to achieve energy efficiency but also aid in the well-being of the occupants of the building. The control of these elements of indoor light, temperature, and looking outside is very important as they are key elements of a healthy indoor environment.

Looking toward the future, glass façades are poised to become even more interactive and dynamic. The integration of smart technologies that allow façades to adjust in real-time to environmental conditions and user preferences will redefine how we interact with buildings. As innovations continue to emerge, glass will remain at the forefront of architectural design, influencing everything from aesthetics to sustainability and beyond.