SHADING IN VENTILATED FACADES

Presentation given by Dr Kragh at the BRE, UK, 29 September 2011.

ES-SO held a Members’ meeting in London on September 30, 2011, one day after a BRE Conference on ‘Solar Shading and Intelligent Façades’ on September 29, 2011 at BRE. The presentation by Dr Kragh, Arup, ‘Shading in Ventilated Façades’, was invited due to the growing interest in the double skin all-glass transparent façades. 

LINK: https://vimeo.com/1025732067

 

FAÇADE ENGINEERING 4.0

Position Paper first published at the Facade Tectonics 2020 World Congress. https://www.facadetectonics.org

Mikkel K. Kragh, Professor PhD MSc(Eng) CEng MCIBSE MASHRAE FSFE. SDU Civil and Architectural Engineering

ABSTRACT

What does the fourth industrial revolution mean to the design and engineering of facades of the future? We are experiencing a global technological revolution and the ‘archaic’ construction sector is at a crossroads. The global challenges of climate and the environment in combination with rapid urbanization calls for radical change in a highly fragmented sector, where definitions of disciplines and construction practice do not readily lend themselves to swift transformation and innovation. Technology and engineering may offer some of the possible solutions, but the challenges of the necessary transformation are formidable and will require new mindsets and new capabilities.

In this context, there is a fundamental difference between what we refer to as digitalization and computation. The façade engineer of the future will need to master computation and information technology in order to integrate complex technology, while still considering a multitude of design parameters pertaining to architecture, constructability, performance, cost and value. The integration and exploitation of computation throughout the different stages of design, delivery and operation of buildings will offer vast advantages through virtually unlimited optioneering, optimization, and hence potential gains in productivity, performance, and quality.

In an almost Darwinian sense, we are likely to see that those professionals and corporations that are able to adapt to and - to some extent - drive these changes will thrive while those that are not willing or able will increasingly struggle and fall behind. The paper outlines the promise of ‘I4.0’ and discusses through examples some likely implications on the practice of design and delivery of architecture and building technology with special focus on facades. Topics covered include automation of design and fabrication, parametric design, additive and subtractive manufacturing, optioneering and optimization, performative architecture, multiparameter decision-making, dynamic façades and transformable architecture, artificial intelligence, digital twins, augmented and mixed reality, robotics and drones.

KEYWORDS 

future trends, computational design, design optimization, parametric workflows, digital fabrication, 3D printing, design processes

INTRODUCTION

The Fourth Industrial Revolution – Frequently referred to as Industry 4.0 – is a term which takes on different meanings depending of context. Digitalization, computational power, connectivity, and automation are all parts of this rapid development and these and other factors are impacting on the construction industry globally. Façade Engineering integrates disciplines, technologies, and connects the phases of architectural projects from conception through to completion, and – consequently – this specialist discipline will not only potentially benefit from new technologies, it will also drive the integration of tools and methods across the field. Besides the development of new cyber-physical technologies and solutions, the façade engineers themselves will need to acquire new competencies and skills in order to master and develop new tools and reap the benefits of future technologies. This paper introduces a range of aspects of Industry 4.0 pertaining to the design and delivery of façades and briefly discusses their implications on the discipline of Façade Engineering and possible future roles and competencies of façade engineers.

AUTOMATION OF DESIGN AND FABRICATION

The digitalization of the construction sector has revolutionized the exchange of data and the amount of information available throughout the ideation, conceptualization, design, construction, and operation of the built environment, including architectural facades. To a large extent, this evolution has converted traditional and conventional ways of working into a digital workflow, where the exchange of data and information occurs in a binary format as opposed to analogue media. At one level we talk about Digitization – i.e. the conversion of analogue information into binary data. We are transferring files electronically as opposed to mailing hardcopy blueprints. Digitalization, however, covers a much broader sense of digital working – i.e. new processes brought about by the advent of digital tools and connectivity. Within parts of these processes, we have seen an uptake of digital technologies, embracing vast opportunities for productivity gains and other desirable efficiencies. The world of Building Information Modeling (BIM) is an example of an area where ‘big’ industry players are making strides, whilst somewhat ‘smaller’ firms and enterprises may be somewhat struggling to keep up or to justify the investment required to upgrade skills and tools.

Automation of design, on the other hand, is a fairly new field, which is likely to impact on engineering in general, and so also on the façade engineering discipline. A number of tasks in connection with design which follows codes and standards can be automated through fairly conventional or even trivial (spreadsheet type) methods. Where engineering judgement is required, where the design is based on first principles, when the design is performance-based, or where multiple criteria are weighed up against each other, the experienced designer plays a significant role. Here, design and engineering is needed to ascertain satisfactory results in terms of aesthetics, function, performance, constructability and cost. At this stage, design documentation and quantities can be produced and shared automatically by information management systems that can be industry standard or specific to a given enterprise or project. As a way of gaining efficiencies, these processes can moreover be approached through parametric design. 

PARAMETRIC DESIGN

Rather than a representing a method or a set of tools, Parametric Design is an entire approach to problem-solving and to design and engineering. We are all familiar with studies of options when dealing with advanced geometry. Specific tools make it possible to modify macro-geometries and study consequences in terms of technical feasibility and architecture. The approach is much broader though, and parametric thinking is increasingly finding its way into areas such as building performance simulation and advanced visualization. Besides being a consequence of developments in computing and software technology, the trend is also testament to a new generation of designers, who are digital natives and apply mathematical and computational thinking to their work as a matter of course or as part of a drive to work more efficiently. In façade design and engineering, the coupling of geometry with performance assessment proves essential when dealing with advanced geometry and evidence-based rationalization and decision-making.

PERFORMATIVE ARCHITECTURE

An example of a field where Industry 4.0 will impact on design and delivery of facades is what is frequently referred to as performative architecture – i.e. the integrated design of buildings or architecture with a strong focus on performance which impacts visibly on the architectural expression of the facades of a given project. A key to successful performative architecture is the ability to adequately asses performance and – depending on the technological sophistication of the concept – the understanding of technical feasibility of advanced components and systems. To this end, building performance simulation is becoming de facto standard and modeling is carried out at various design stages to varying degree of detail. Essentially the architecture reflects the concept of engineered performance and evidence is typically provided through sophisticated performance simulation that goes beyond empirical data, conventions, and standards.

As the tools are evolving, it gradually becomes possible to include complex systems in the models and consider multi-parameter, multi-criterion decision-making as an integral part of the design process. Dynamic facades and – more broadly - transformable architecture require complex technological solutions that need to be informed through engineering, which tends to cross traditional boundaries of disciplines and trades. Parametric approaches and integrated performance simulation should be coupled with insights and experience into technical feasibility of automation. The key is the ability to adequately articulate architectural intent and technical requirements in the communication with the design team and in contractual documentation.

ADDITIVE MANUFACTURING

A detailed discussion of the broad term Additive Manufacturing (AM) or 3D printing goes beyond the scope of this paper. Additive Manufacturing is a compelling technology which crosses the boundary between design and engineering of form and matter, bridging between design and fabrication. The potential benefits are numerous, and the 3D printing industry is developing at a fast pace.

The ability to manufacture bespoke components and tune material properties may yield advantages in terms constructability while making possible optimal solutions for a given set of circumstances and requirements. The distributed fabrication of parts potentially impacts on both logistics and design concepts.

Bespoke components and new materials are posing challenges in terms of verification of performance, code compliance, and certification. Consequently, development of reliable engineering tools and fully integrated performance simulation in the computational design process is going to prove instrumental to the viability of digital fabrication of components for construction. 

ARTIFICIAL INTELLIGENCE AND MACHINE LEARNING

There is much talk about smart components, smart buildings, and smart cities. We are currently seeing numerous systems and components that allow for control and automation, but we are yet to witness a real breakthrough in truly Intelligent buildings and facades that will learn and adapt – for example on the basis of user behavior or preference. Or  even predict and adjust on the basis of weather forecasts and analysis of historic data.

Algorithmic, rule-based design and operation is not new. What is new is the opportunities offered by big data, computational power, and connectivity. Whilst the term Artificial Intelligence implies that processes are based on logic and algorithms, Machine Learning goes further to suggest that data is provided to computers that in turn will learn for themselves. 

Big Data and the Internet of Things and  connectivity and access to data are ever-increasing. The ability to process this data represents business opportunities and potentially enhanced operation and performance of buildings, including facades. We are starting to see software engineering in the field of automated diagnostics and fault detection. Building management systems of the future are likely to be more attuned to occupant behavior and preferences. Such systems, however, will only be successful provided that they are based on deep understanding of building design and operation. The value of such systems lies in the quality of data as well as the ability to extract meaningful information. 

Besides opportunities for improved performance in operation, the use of artificial intelligence and machine learning is increasingly becoming an opportunity for optioneering and optimization in the design and engineering of buildings.

OPTIONEERING AND OPTIMIZATION

The ability to model and simulate with sufficient accuracy coupled with increasing computational power offers interesting opportunities for optioneering and optimization. Through a structured and systematic variation of multiple parameters and analysis of results in terms of preselected criteria, we can afford to ‘test’ ever-increasing numbers of options and scenarios. The key here is the reliability of the models and the appropriate definition of assessment criteria. Given that, in façade engineering, the optimum is usually obtained as a compromise between completely different design aspects, the definition of rules and criteria is far from trivial. If only one well-defined aspect is considered, the task is comparatively simpler, but the trend is towards more involved models of multi-physics, economics, and other critical factors.

Topology optimization methods are enabled by supercomputing and represent significant potential for optimization when coupled with parametric design and digital fabrication such as additive manufacturing. In essence, topology optimization can significantly reduce the amount of a material used through advanced engineering and supercomputing of a multitude of options. The objective is to build ‘More with Less’, saving resources and reducing weight. The approach may be based on project constraints or open a more open space of solutions. The results often lead to forms resembling structures found in nature and they can also be defined based on inspiration from nature, as so-called biomimicry. As methods and tools evolve, such non-conventional construction forms are likely to become a key part of façade engineering and fabrication.

In the construction sector in general and the façade field specifically reliable models and design methods are fundamental. Research is therefore required to provide methods and tools that adequately represent what can actually be manufactured and built whilst exploring and engineering alternative integrated design options.

DIGITAL TWINS

A digital twin is a comprehensive representation of entire systems that can serve to test different scenarios and possible alterations. Digital twins represent opportunities to trial designs virtually through advanced performance simulation and building management systems. User behavior and scenarios can be varied with a view to enhancing both building performance and user experience. Simulation is also used to design fabrication processes in the field of Automation, and this is likely to become an integral part of computational design and digital fabrication of facades. Rather than developing a concept, engineering it, and transferring the information to a production environment, the objective is to integrate these environments and design for manufacture and assembly. To some extent this is already happening, and progress is being made in the coupling of engineering with information on feasibility of digital fabrication and constructability.

AUGMENTED AND MIXED REALITY

New technologies in visualization are made possible through a combination of detailed digital modeling and enhanced power of computation. Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR, i.e. AR and VR together), are increasingly utilized to make available information in user-friendly and highly interactive formats. The prospective applications are numerous and include elements such as: communication of design options to non-experts, user involvement, co-creation, training, remote instruction, and public relations, to name but a few. 

In the field of façade engineering, the access to interactive user interfaces in training and education, as well as on site and in a production environment, will not only potentially enhance productivity and competitiveness – It may also facilitate design team communication and replace comparatively costly physical mock-ups.

ROBOTICS AND DRONES

Automation and the use of robotics in construction represents potential gains in productivity and built quality. It may also ultimately eliminate dangerous, dirty, and dull work to the benefit of health and safety of workers. The health and safety aspects are also the focus on collaborative robots. One of the current challenges of robotics in construction is the non-standard conditions on site, which represent unpredictability, risk, and substantial added complexity to any automated process. 

The quest for automation and construction robotics is partly driven by the ability to deliver customization and complex geometries at marginal added cost. A major challenge in making these solutions attractive is that current standards and design practices are developed for human labor and that consequently it is not straightforward to capitalize on advanced construction processes. The shift is likely to happen through a combination of industrialized off-site or even on-site fabrication processes and design for robotized manufacture and assembly. Façade design and engineering will thus need to reflect novel processes and constraints, which may not currently be considered by codes and construction practices.

In this context, drones can be simply seen as unmanned aerial robots with the potential to access hard-to-get-to areas and facilitate remote surveying and inspection, installation, and maintenance. Coupled with virtual and augmented reality this is likely impact to significantly on the roles of personnel in connection with façade installation and maintenance.

SKILLS AND COMPETENCIES

By nature, the discipline of façade engineering covers a vast array of aspects pertaining to aesthetics, building envelope function and performance, structure, physics, materials, constructability, cost, construction management, and procurement strategy. Façade engineers work across the value chain as either generalists or more or less specialized professionals. Industry 4.0 and in this paper Façade Engineering 4.0 - is shorthand for the technological (r)evolution we are currently witnessing. The rapid pace of technological progress presents tremendous opportunities. The progress, however, also puts pressure on the skills and competencies required to offer sound advice and deliver successful facade design and engineering. New competencies are required in order to unleash the potential for buildings that are optimally valuable to their users, their owners, to society, and to the planet. From concept to completion through operation and end-of-use the façade engineer needs to master computational design and more or less advanced digital tools. This means design for manufacture and assembly in a digital workflow, adopting a parametric approach and incorporating knowledge about automation and digital fabrication, as well as adaptive systems and performance assessment. Over the past years, a new generation of computer-savvy designers have successfully created new roles and jobs across the industry with focus on parametric design and advanced building performance simulation. The coming years will see this computational way of working expanding across the design and construction community.

THE ROLE OF THE FAÇADE ENGINEER

The façade engineer integrates disciplines, trades and technologies. As an integrator, the façade engineer also holds the key to identifying appropriate solutions to complex problems. In the context of the Fourth Industrial Revolution, or Industry 4.0, this role is facilitated and empowered by ever-more evolved design tools. The role is challenged through myriads of new technological developments pertaining to the design, production, assembly, and operation of modern architectural envelopes. It is likely that the palette of specialist offerings will continue to broaden as this will allow for high value services. It is, however, paramount that the generalists are conversant with the numerous novel aspects of technology in façade design and delivery. A blurring of boundaries between traditional disciplines in unavoidable and this is an opportunity, provided that the façade engineers are willing to engage with the brave new cyber-physical world of Façade Engineering 4.0. Notwithstanding this, the fundamentals of tectonics and engineering remain key and cannot be replaced by automation of design and algorithms. It is therefore likely that the role of the façade engineer will be even broader than it is today. Optioneering and optimization will become accessible more readily through parametric working, computational power, and automated tools, while comparatively mundane code compliance checks will be incorporated and not constitute time-consuming tasks. The ‘4.0’ façade engineer will thus need to understand digital fabrication and will also need to collaborate with researchers and industry. The aim will be to contribute to next generation façade solutions and fabrication techniques that are maximizing the benefits of automation without incurring excessive costs thus maximizing value and worth.

CONCLUSION AND FUTURE WORK

The Fourth Industrial Revolution, also known as Industry 4.0, is impacting on façade engineering as methods, tools, techniques, and manufacturing and installation technologies evolve. Some will say that the construction industry has not yet reached 4.0, but the fact remains that computational design and digital fabrication, along with connectivity, big data, and artificial intelligence, are already now impacting on the visionary world of façade engineering. Façade Engineering is a pivotal part of the integration of disciplines, technologies, and trades. Future work will follow numerous parallel and intertwined paths as the skills are broadened to adopt a digital way of working and develop a higher degree of automation in design and delivery. Façade Engineering 4.0 will be enriched by parametric ways of working and the coupling of digital design environments from design to production. To this end, a significant effort is required to transform traditional processes – intrinsically based on human labor and manual engineering – into processes that are structured to reap the benefits of automation and computational design. Research, development and innovation will offer opportunities to enhance productivity and quality, while crucially contributing to a global sustainable development.

The Value of Design - Part I

PUBLISHED BY INTELLIGENT GLASS SOLUTIONS IN IGS ISSUE 4/2013

"Good design doesn’t cost, but it pays." [Richard H. Driehaus]

ABSTRACT

What is the value of good design?  Design as product, process, or both?  This fascinating question triggers discussions of design and the relationship between aesthetics, quality, and architecture.  It also highlights the interesting relationship between, on the one hand, value in monetary terms – good design is potentially good business – and, on the other hand, value in qualitative terms – potentially experienced as the worth of a building or a space.  The article attempts to relate these questions to High Performance Facades and some of the challenges facing the industry in the future.

METRICS

So how do you measure the value of design?  As engineers, we are used to dealing with performance requirements fairly routinely and comfortably and the current energy performance debate centres on the performance gap (between the design targets and the performance delivered in operation).

In certain parts of the market, there are expectations in terms of the ‘standard’ of construction, but how do you measure this beyond construction budget?  When it comes to aesthetics and the qualities of fabric and space it becomes more complex and more ‘soft’ measures are usually applied. 

The discussion is not purely academic.  We are starting to see hard data on the economic value of design as research explores the market value of property designed by signature architects.  The details of the science lie beyond the scope of this article, but it is relevant to mention that this is an area of interest from the perspective of the most commercially astute investors and developers.  One such study states “ (...) compared to buildings in the same submarket, office buildings designed by signature architects have rents that are 5-7% higher and sell for prices 17% higher.” [F. Fuerst et al., Henley Business School, University of Reading, UK].

"Good design is good business." [Thomas Watson, Jr.]

DESIGN AS A PRODUCT

The term design used to describe the product can take on a wide range of meanings and cover a number of characteristics, including aesthetics.  It is also frequently associated with elements pertaining to quality, which can lead to challenges in terms of communication across design team and supply chain, and beyond. 

A design can be characterised by appearance, function, and performance.  Notwithstanding this, the quality aspect is critical and this is where terms such as durability and longevity become highly relevant.  Quality here refers to the detailing, quality of materials, and workmanship, but also to the ‘softer’ architectural qualities of fabric, texture, and space.  High quality buildings that are pleasant to live, work, and play in, and also benefit the surrounding environment, are more likely to be looked after and last longer.  In the long run they are therefore worth more than buildings of lesser quality.  Such qualities can be difficult to measure and quantify, but the suggestion here is that there is significant value in good design and that this translates into the worth of a building and/or a place.  

DESIGN AS A PROCESS

Good design depends on a good design process.  Over the past decades, there has been much talk about the integrated design process and interdisciplinary working.  It is now generally agreed and understood that successful building projects are usually the result of a thoroughly collaborative process where the design team responds appropriately to the client’s requirements.  “The devil is in the detail”, but great designers have taught us how to translate the inherent complexities of architectural design into subsets of interlinked decisions with an eye on the overall result.  Paraphrasing, the late Sir Ove Arup spoke of Total Architecture when he addressed architecture and engineering as inseparable parts of design.

Good collaboration and the integration across disciplines and the supply chain will facilitate management of risk – financial as well as technical.  Ultimately, the link between the architects and the suppliers is a way of managing architectural intent as the feasibility (cost, time, quality) of alternative options can be assessed from the early design development.  Specialist advice (such as facade engineering) can prove instrumental to proving the feasibility of innovative solutions and adequately manage integration across disciplines.

The pitfalls are around every corner.  The value of design in this context relates to the nature and quality of the collaboration and the ability and capacity to translate the client’s requirements into concrete design proposals.   

VALUE ENGINEERING

Value engineering usually focuses on cost reduction in response to indications that the design may run over budget.  When carried out late in the design process the options are frequently fairly limited and the result can be that the project is stripped of what may be deemed superfluous design elements in the pursuit of best value.  It could be argued that value engineering is a necessary and intrinsic part of a healthy design process and that it should not actually be possible to trim elements of a good design.  The key here is that an investor needs information on both cost and value to make informed decisions and the design team needs to be able to articulate and assess options as well as the consequences of alternative design decisions.

"When I am working on a problem, I never think about beauty. I only think about how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." [Richard Buckminster ‘Bucky’ Fuller]

WHAT JUSTIFIES A PREMIUM?

In the context of value engineering and with a focus on return on investment as the key success indicator of commercial development, it is perhaps interesting to consider what kind of elements may justify a premium.  As discussed briefly above the potential premium fee of a signature architect may be justified on the basis of image, marketability, and market value of real estate.  In some cases specialist services such as facade engineering are seen by the client as ‘additional’ but justified because they are perceived instrumental in terms of managing technical risk and timely delivery.  Then what constitutes a premium, actually?  Well it depends on circumstances, but in the context of this discussion it relates to design beyond the baseline minimum necessity.

Double skin facade solutions are a prominent example of premium architectural solutions.  They offer a range of distinct architectural expressions and – importantly – they typically offer varying degrees of transparency through the extensive use of clear glass and shading devices protected from the elements.  Besides adaptable function and performance, the layering and depth of the double facade add a desired aesthetic quality to the design.  Studies show that it is hard, if not outright impossible, to justify the additional cost of these solutions on the basis of energy savings when comparing with more conventional solutions.  The premium is thus justified on the basis of less tangible qualities and the decision to pursue this style of facade derives from informed dialogue between the architect and the client.  Whether the budget is subsequently taken for granted or subject to further justification varies from project to project, but the point is that the premium is justified on the basis of the value of the design.  Similarly, in certain locations and markets, there are requirements in term of architectural language including use of certain materials.  Banks may want to project a ‘solid’ appearance of their headquarters and opt for the use of natural stone, which will represent a premium.  The requirement for natural stone may also derive from planning regulations and be seen as a price for development in a certain premium location. 

A recent research study by the Council on Tall Buildings and Urban Habitat (CTBUH) highlighted the relationship between the height to architectural top and the height of occupiable space for recent prestigious high rise buildings.  Somewhat controversially, and perhaps actually ‘tongue-in-cheek’, the height of non-occupiable space at the top of the high rise building was dubbed Vanity Height (up to 39% of the height to architectural top) and this subsequently spawned a heated debate in the industry.  The point is that, for a number of reasons, investors are willing to invest vast amounts in architectural elements that are - by definition - beyond the baseline minimum necessity when they are seen as adding value to the design. 

The added value of design is a theme worth discussing also in relation to high performance building.  Traditionally options are judged on their cost for equal performance and a parallel discussion deals with architectural intent and quality.  It is time that these strands of discussion merge and that the architectural merit of high performance solutions is taken into account as a matter of course as they may add to the worth of the solution. 

HIGH PERFORMANCE DESIGN

Dow Corning has responded to the need for more integrated solutions in the field of high performance building and now engages in the development of a broad range of innovative solutions in collaboration across the supply chain.  In the construction sector, the company is traditionally known for excellence and innovation in sealants and structural glazing based on a long history in Silicon science.  As a more recent strategic direction, the company now provides custom solutions and work closely with designers as early as concept design where key design decisions are made.  As part of this effort, the company now employs facade engineers who link the research, development, and innovation work with the field.  This connection creates synergies where the designers are equipped with new solutions in the pursuit of new design possibilities.  Through this early stage engagement, the designers can freely explore options, while gauging their feasibility thus minimising risk including the exposure to the dreaded redesign post value engineering.

An example of novel high performance facade solutions is the Dow Corning Architectural Insulation Module – an opaque thermally insulating facade module incorporating vacuum insulating panels and insulating glazing unit technology.  The technology sets a new benchmark in performance which potentially translates into very thin building envelopes and trade-offs between vision and non-vision areas (WWR, window-to-wall ratios).  While the performance levels are interesting in their own right, the really intriguing aspect here is the impact this novel technology can have on the architectural expression of high performance building envelopes generally and curtain walling in particular.  Instead of asking for the technology to deliver a certain specified performance, you can now start to ask what impact the technology may have on the architecture.  For instance, what if the wall could be 60mm thick instead of 300mm?  This leads on to discussions about the value of lettable floor area, but also the value of a certain aesthetic or the qualities of the space.

GREEN IS THE COLOUR ...

Indoor environmental quality and occupant comfort are shown to impact on productivity, staff retention, and corporate image.  Evidence shows that the financial impact of these factors is substantial and more significant than the energy savings for an occupier of an office building.  The marketability of a building is another significant commercial element where buildings with high environmental ratings are attracting tenants quicker than similar buildings without ratings.  In certain markets incentives are given to developers who can demonstrate the environmental performance.  Such incentives can include permission to develop more area, tax benefits or other benefits in connection with planning process.  Finally, high performance solutions may offer ways of exploiting the real estate, for example through use of more compact facade systems.

In addition to the economic value of design as pointed out above, other metrics include the environmental impact ratings such as LEED and BREEAM, which are increasingly used as a marketing instrument, attracting environmentally conscious tenants and buyers.  Energy Performance Certificates are also widely expected to become a commercial factor as prospective tenants or buyers will start to negotiate on the basis of energy consumption or even the likelihood of required energy upgrades to the building fabric and plant.

In addition to the environmental drivers, there are plenty of potential commercial benefits of high performance building. 

Add to the environmental benefits and the marketability the potential worth and longevity of well-designed buildings and a new paradigm is emerging – Or is it new, really?  Create high performance buildings and spaces of high architectural quality their worth will last.  The challenge remains how to manage and deliver projects where longevity and worth are valued along with cost and price.  Perhaps new columns are needed in the project manager’s spreadsheets and new measures are needed for clients to assess their options.  Educated clients and developers realise that good design – including high performance – is good business – Green is the colour of money ...

"What works good is better than what looks good.  Because what works good lasts." [Ray Eames]

Words #003

 “ Whenever you see the word ‘green’ in the name of a building code, cross it out and write the words ‘high performance’ instead.  When green criteria move into the building code we will be looking at a new normal.  And meeting the building code is not something the majority of architects is going to hire a consultant to do.  It is an opportunity for us, as a profession, to build new value for what we do.”

 [AIA. Design:Art+Science. Episode One.  Hosted by Jennifer Devlin-Herbert, FAIA, Principal at EHDD]

Words #002

(...) we should be wary of focusing our argument on the bottom line. Architecture and design are fundamentally useless activities when viewed through the lens of a project manager’s spreadsheet. That’s why so much bad design is commissioned: because it doesn't make any difference when it is totalled up in a column. Project managers get fired because buildings are late or go over budget, but rarely because a building isn’t very good.

[Sam Jacob, FAT, column in Dezeen Magazine]

High Performance Defined

EXECUTIVE BOARDROOM COMMENTARY PUBLISHED BY INTELLIGENT GLASS SOLUTIONS IN IGS ISSUE 4/2012

The theme of this year’s Glass Supper is Firmitas, Utilitas, Venustas (Firmness, Commodity, Delight) from Vetruvius’ elements of architecture.  The theme provides an excellent opportunity to reflect on the importance of the building envelope as it combines functional requirements with performance and aesthetics.  The strap line of the event is: Where will the architectural glass industry be in 100 years time?  In times of economic and environmental challenges it is quite appropriate to consider how Architecture will undergo changes and how these changes will impact on the construction industry.  It is both interesting and relevant to consider how new drivers including legislation will bring about changes at different scales – from urban design to material science.  At the Glass Supper we will be focusing principally on architecture and glass, current challenges and future opportunities.  High performance buildings with low environmental impact require collaboration across design disciplines and supply chain.   The aim is to create durable and resource-efficient buildings of high architectural standards – More with Less is the overarching ambition.  The devil is in the detail and so besides much-needed technological progress and a deeper understanding of fundamentals it is of paramount importance that designers are empowered to adequately consider high performance solutions at the early project stages.  The designers will need new skills in the future and they will need access to the right information from suppliers and contractors.  While the need for interdisciplinary working and integrated design has been acknowledged for years, legislation is likely to require closer links between designers and supplier to meet the stricter regulations of the future.  It is well-known that building regulations will never represent cutting edge solutions – That is not the role of legislation.  The environmental policies on the other hand will drive change and we all need to reflect on our own role in a changing set of circumstances.  Thought-leaders set new standards and – by doing so – aim to secure a place in the future marketplace for high performance building solutions.  Innovate or stick with business as usual?  Lead or follow? 

HIGH PERFORMANCE AND LOW IMPACT

One definition of a successful building project is “a project that will meet or exceed the Client’s expectations, be delivered on time and on budget”.  How do you then define high performance?  Well, it depends on the point of view.  The term high performance building will typically cover aspects of durability, energy savings, occupant comfort, and aesthetics.  The specific context and the Client’s requirement will determine which of these aspects are of high priority and which are negotiable.  Increasingly, low environmental impact is seen as high performance.  By some forward-looking designers it is even seen as a given and not really the subject of much discussion. 

Visionary clients and developers – with the help of their designers – target high performance because of its impact on corporate image, staff retention, and potential savings on operational costs.  Comparatively less visionary clients and developers will follow suit as legislation tightens the requirements.  Environmental rating schemes are meant to affect the way projects are delivered, forcing project teams to work together more closely and assess options early on in the project.

Some clients and project teams aim beyond code, and target environmental ratings which are not strictly required by legislation.  However, ambitious targets can be hard to justify unless the design team can provide evidence and demonstrate that the cost premium is not excessive.  The onus is therefore on the design team – in close collaboration with contractors and suppliers – to develop and communicate solutions, which offer design advantages without incurring excessive or even prohibitive cost premiums.  In a sector where the focus traditionally is on first costs a paradigm shift is required if due credit is to be given to high performance.

Add to the perceived cost of high performance the aesthetics and the fairly delicate discussion about architectural quality.  This is the Delight element - Venustas - which is both subjective and often difficult to define as it encompasses qualities such as light and shadow, transparency and reflection, colour, texture, materiality and form language. 

TRANSPARENCY AND BEYOND

Over the past decades, highly transparent facades have become almost the default expectation in high end commercial developments.  For these systems to perform to the ever stricter energy performance requirements they are often realised as so-called double skin facades, which is an effective way of offering variable performance and a high degree of transparency when solar shading is not required.  The variability of the facade including the shading system in effect becomes an important part of the architectural expression.  Thus it is possible to offer high performance though dynamic systems.  The premium for these solutions is more often than not justified in an architectural discussion where transparency is a key performance parameter or a fundamental requirement. 

Progress is being made in the field of switchable glazing as a means of controlling transmission of solar radiation within the glass itself.  Liquid crystal display technology is being used in privacy applications and the potential in daylighting application is being explored.  Also here, Dow Corning is actively pushing the envelope, introducing silicon science in this new field of high performance architectural applications. 

The pressure to reduce carbon-intensive cooling in buildings has led to a reduction in the ‘default’ fully glazed facade.  Architects are finding new forms of expression, where the non-transparent (non-vision) part of the building envelope gains prominence as an alternative aesthetic for energy efficient buildings.  In this context there is growing interest in materials and geometry as ways of breaking up the building elevations and moving away from the now conventional spandrel strip and floor-to-ceiling vision glass.  We are witnessing a trend where the building envelope becomes colourful and in some instances even playful – again adding an element of delight.   

Reducing the vision area is obviously a very efficient way of dealing with solar gains and the resulting, carbon-intensive cooling.  And obviously the impact on daylight availability should always be considered to provide occupant visual comfort and reduction of energy used for electrical lighting.  As the vision area reduces and the architectural language starts to involve potentially complex detailing of the insulated parts of the building envelope, the thermal performance of the facade depends closely on how the insulated areas are detailed and in curtain walling the effect framing needs to be taken carefully into account. 

The thermal performance of curtain walling needs to be assessed for the whole assembly, including vision area glazing, insulated areas, and – crucially – the framing.  Projects with relatively limited vision area percentages and complex detailing of the opaque, non-vision areas will increasingly require high performance thermal insulation to meet performance requirements given common space constraints.  One such novel solution utilises vacuum insulation panels (VIP) as a means of offering the highest thermal performance within a given available thickness or – interestingly – compacting the thickness of curtain walling for a given performance requirement.  Dow Corning’s architectural insulation modules are based on well-known IGU technology, enhancing the performance of non-vision areas through integration of fumed silica core VIP solutions. 

THE SPECIFIER AND THE SUPPLIER

In a sector where there is no ‘one size fits all’ and virtually every project is different there is inevitably an element of risk management, which stands in the way of project-specific optimisation.  In a time where the economic climate and the environmental agenda present challenges, there is an increasing focus on integrated project delivery.  Important design decisions are made at the outset of projects with subsequent changes being potentially both complex and costly.  Therefore, as environmental ratings creep up the agenda and priority is given to early stage optioneering, the relationship between the design team – or the Specifiers – and the suppliers is of paramount importance.  Why?  - Because the design team can only ever develop successful solutions if they have access to detailed information on relevant options.  The suppliers in turn need to be able to articulate in an appropriate and relevant format the characteristics of their offering, including performance metrics and design constraints.  This working relationship will eventually lead to the development of novel solutions based on feedback from cutting edge project work and the experience of highly skilled people. 

COST, VALUE, AND WORTH (GREEN IS THE COLOUR ...)

High performance is desirable for an owner-occupier due to long term benefits.  To a commercial developer, however, high performance is typically more interesting in terms of marketability as environmental performance becomes a central commercial parameter in negotiations.  Environmental ratings are increasingly seen as a differentiator in the commercial market, with prospective tenants comparing the ratings of property on offer – all other things equal.  It is likely that there will come a time where property cannot be let or sold if its energy performance certification falls short of certain thresholds stipulated by regulation.  In such situations building energy performance translates into capital value as upgrades will have to be factored into the negotiation.  This aspect will inevitably affect decision making which, incidentally, is the purpose of the policy directives.  And then there is the question of planning permission, which can depend on convincing evidence of environmentally conscious design principles.  This can be a key element in terms of technical and commercial risk as it can be costly and time consuming if planning against expectation is not granted and redesign turns out to be necessary. 

Then there is another aspect of Design, which pertains to the high end of the property market, where aesthetics and choice of materials impact on market value.  The client brief will set out the requirements and the designer will be chosen with due regard to reputation and ability to deliver such high end projects.  In these situations, the designers ability to consider appropriate technical solutions early on is likely to prove critical to proving the feasibility and avoid costly abortive work.   

In addition to the crucial durability of solutions, a key component of environmental performance is the lasting qualities of buildings.  A quality building is more likely to be looked after by its owners and users and it is more likely to be adapted to changing requirements over time.  The quality comes through in carefully crafted fabric and detailing as well as the nature of the space within and around the building.  Future proofing buildings through high performance will inevitably add to their worth and this should ultimately translate into commercial value.

It is not all doom and gloom as progress is being made on many fronts including materials science, building envelope technology, and design tools.  High performance building solutions will require new solutions bridging sectors perhaps not conventionally or traditionally associated with construction.  The ability to modify the properties of construction materials will cater for enhanced performance and durability, provided that the materials are used appropriately.  Outside of sealants and structural glazing, silicon science is a field which is not widely considered part of the high performance building arena.  Well, that may change as Dow Corning continues to collaborate in pursuit of high performance solutions with low environmental impact on the route to the net zero buildings of the future.

Curtain Walling Energy Performance - Next Generation

Energy consumption in buildings account for approximately 40 per cent of the global energy consumption and regulations are getting ever stricter in an effort to meet targets set at international and national level.  Ultimately, near zero carbon emission buildings will become the norm and this puts pressure on the building envelope to perform to higher standards than current practice.

In a time of ever stricter energy codes, high performance is seen as a means to an end – Empowering the Designer to deliver high quality architecture with low environmental impact.  We are talking about Design Freedom.

Novel solutions include architectural panels – robust products which can be handled during assembly and installation.  The technology is that of insulating glazing with vacuum insulation panel (VIP) inserts offering enhanced thermal insulation in compact units.  The finish is optional and the thickness is driven by performance requirements.  Or – as is often the case – the solutions offer maximum thermal insulation where a thin envelope is desired or required.  Potentially the thermal performance of a conventional wall is achieved within the space of a conventional glazing unit opening up new opportunities for architectural design.  The first projects have been realised already, spanning from retrofitting of historical buildings with architectural and space constraints, to new build rain screen cladding solutions with high performance.

The fact that vacuum insulation panels offer the performance of a conventional insulated wall contained in a glazing unit opens up new architectural avenues and breaks down some of the barriers otherwise posed by stricter energy regulations.  Examples of design freedom offered by high performance include the ability to increase the percentage of vision area, additional play with geometry such as layout and 3D form language – all due to enhanced performance in the insulated areas, offsetting the performance of vision area, increased transmission area, and linear thermal losses.

In a time where the energy performance of buildings needs to be addressed not only by visionary designers and clients, but across the board, the challenge is to not sacrifice high design freedom and quality architecture.  The performance of curtain walling has been enhanced incrementally over the past decades and it is reaching certain limits mainly due to the need for vision area and the inevitable effect of the framing.  Well, a step change in insulation performance may quite possibly offer new opportunities for curtain walling in a world of High Performance Building.