4. Disruption in the Built Environment
Key points
- Disruptive trends in the built environment could change the role of cement and concrete, and redefine the opportunities for innovation and decarbonization in the sector.
- Changing how we build could have a major impact on the volume of concrete needed, and there are many exciting developments around materials and design.
- The changing politics around the built environment are reshaping the expectations of publics and policymakers and affecting what is built and why. This is occurring in the context of growing popular interest in ‘inclusive’ built environments, rising environmental sensitivity and increased awareness of the need for resilience to climate shocks.
So far this report has focused on disruptive innovations that could lower the carbon content of cement and concrete. This chapter considers disruptive innovations that could lower the carbon content of buildings and structures and reduce the carbon emissions associated with their construction and use. It also considers innovations in terms of the implications for so-called ‘end of first life’ processes – such as the demolition of buildings, the recycling or reuse of materials from them, the repurposing of buildings and structures for other uses, and so on.
Considering the role of cement and concrete within the broader context of the built environment is important for two reasons. First, it introduces the possibility of establishing a new set of emissions mitigation levers, based on design and material efficiency and how buildings are used. Second, it allows us to think about solutions to the larger environmental impact of buildings and construction, which respectively account for 28 per cent and 11 per cent of global energy-related CO2 emissions.347 Decarbonizing cement and concrete alone will not solve this broader issue, but it could play a contributory role. At the same time, changes in the built environment could feed back into the cement and concrete sector – promoting consumption of cleaner products or helping lower overall demand.
Broadening the boundaries of the debate might reduce clarity over ‘ownership’ of – and responsibility for – decarbonization, but new approaches could be developed to address these issues. This question of boundaries is not limited to cement and concrete; there are examples across the economy as traditional sectoral demarcations blur. Assessing progress on decarbonization across the wider built environment is a logical end-game, but narrower, sector-specific goals will remain critical given the scale of cement use.
This chapter maps out the landscape of emerging or prospective disruptive changes in the built environment. It starts to explore what these changes could mean for the decarbonization of construction, as well as – where possible – for the decarbonization of cement and concrete specifically.
The chapter divides these disruptive trends into two categories. First, there are the profound changes in what we build – led by different expectations, shifts in behaviour and the need for resilience to more turbulent climatic conditions. Second, and underpinning these changes, are the shifts in how we build, underpinned by breakthroughs in design and construction methods and the leveraging of data to optimize the use of buildings and infrastructure. This latter category of trends centres on developments in technical innovation, engineering, and the services around them.
At present, it is challenging to put numbers on the likely impact of each of these changes, let alone estimate their aggregate impact at the system level. These are fast-evolving trends and there are few robust models; suggestions for ways to help fill this gap form part of this report’s recommendations (see Chapter 5).
4.1 Building for the future
There remains much uncertainty over how changes in society will shape the future urban environment. Yet to a great extent these will determine what a climate-compatible pathway for cement and concrete could look like.348 Several factors are important in this regard:
Shifts in demographics and behaviour
Demographic shifts are a key factor shaping the types of buildings needed. In many regions, populations are getting older,349 requiring a greater focus on subsidized supportive housing, accessible workplaces, and mobile health and personal support services. At the same time, in many countries younger people are increasingly choosing to live in urban spaces within walking distance of public amenities.350 Another trend is that more people are choosing to live alone.
Although city planners need to respond to these trends, they can also help define patterns of energy and resource consumption.351 The way in which a building or a city is laid out strongly influences how people and materials move around – and, once built, infrastructure can lock in behavioural pathways for better or worse. Urban design based on a ‘capillary web’ system and around pedestrians rather than cars, for example, can lead to two-thirds less driving and one-third less concrete being used.352
Emerging and developing countries have an advantage here: by making the right choices today, they can avoid some of the environmentally costly effects of urbanization in developed economies.353 Growth in urbanization in the US around the 1920s, at a time when private car ownership was on the rise, resulted in cities designed around cars.354 These sprawling cities in turn reinforced dependency on car ownership. A climate-compatible built environment will, therefore, depend just as much on building the right infrastructure as on building more infrastructure.
A climate-compatible built environment will depend just as much on building the right infrastructure as on building more infrastructure
Accountability and public expectations
Cement is largely a hidden material, in that end-users do not generally think about their consumption of it or consider the environmental implications of that consumption. Although the choice of building materials can have a large impact on living standards, prospective house owners do not tend to choose dwellings based on the materials used; nor do they think about the long-term effects of those materials on the environment and their enjoyment of the structure in question.
The choice of building materials only seems to be revealed in the event of catastrophe. Earthquakes in China and Italy, for example, raised awareness of shoddy building standards and of corruption that allowed regulations to be circumvented.355 The 2017 Grenfell Tower fire in the UK led to increased political demand for accountability about the decisions taken with regard to cladding and materials used in public housing and more broadly.356
As public awareness of the climate impacts from infrastructure and construction increases, publics may well demand a more environmentally friendly built environment; after all, consciousness around urban air quality has soared in recent years, and the same may one day be true of public attitudes towards the built environment. There may also be demand for stronger, more durable and more flexible buildings.
Digital trends shaping urban life
New technologies are changing approaches to city planning and management. Real-time information from connected devices has given cities new ways of delivering services (examples include the shift towards digital traffic management in Nairobi, Kenya;357 and the use of smart, connected waste-management systems by some local governments in the UK).358 Enhanced transport and logistics allow for good-quality urban living at much higher densities than used to be thought possible.359 This can dramatically reduce energy and resource consumption.
The trend towards automation in the workplace could affect the types of buildings constructed. Fewer office buildings may be needed, less space and lighting will be needed in some workspaces, and there may be more demand for communal and multi-purpose spaces.360 Office buildings could end up offering a large stock of new living spaces, reducing the need for construction of new buildings.
Spillover effects between different sectors shifting towards a low-carbon economy could have an impact on what is built. Electric cars, for example, will lead to cleaner air and less noise. This could encourage the use of natural ventilation and passive heating and cooling – designing a building to be warm or cool without the need for heating or cooling – in place of air-conditioning as a means of temperature control.361 More energy-efficient buildings can reduce fuel consumption for heating and contribute to improved air quality.362 In northern China, for example, high-performance building envelopes – the physical barrier between the exterior and interior of a structure, i.e. walls, floors, roofs and doors – could help reduce air pollution as less coal would be burnt for heating in winter.363
Climate-compatible infrastructure
Resilient infrastructure will be particularly important in emerging economies and developing countries, which are likely to experience the worst effects of climate change in the short to medium term.364 The future built environment has to be resilient to climate-impact risks (e.g. sea-level rise) and address growing concerns over natural hazards (notably flooding and hurricanes). There will likely continue to be a need for high-strength traditional building materials, including concrete to build higher sea walls and stronger flood defences, and to strengthen critical infrastructure.
Novel, smarter and more adaptable materials will likely also come into play, with use in structures that can withstand extreme temperature changes and very high winds.365 These materials will be particularly important where traditional materials are affected by climate change. Several studies highlight the impacts of climate change on concrete infrastructure. Humidity and increased concentrations of atmospheric CO2 can speed up corrosion in concrete.366 In regions where these effects are expected to be more pronounced, the use of thicker concrete, more rigorous maintenance, and the application of surface coatings are being suggested as potential means of mitigating damage.367
Beyond reducing emissions from the construction and operation of buildings and infrastructure, there may be an opportunity to leverage the built environment as a carbon sink. Opportunities in this area range from the fairly non-technical (covering the walls and roofs of buildings with plants)368 to the highly technical (using building materials designed to sequester CO2).369
4.2 Building differently
A more sustainable built environment may not only rest on what is built but on how we choose to build in the next few decades. Changing how we build could have a considerable impact on CO2 emissions. This will be contingent on disruptive innovation at five key points along the construction value chain: design, materials, construction, operations and use, and end-of-first-life.
The share of emissions that stem from these different stages can vary considerably depending on location, design and application.370 However, in general, the bulk of emissions lie in the operations and use phase of buildings and structures. For example, in 2008, an estimated 83 per cent of UK construction-sector CO2 emissions came from the use phase versus 15 per cent from the supply of construction materials; of the latter, 28 per cent came from the use of cement, lime and concrete products (see Figure 26).
As a result, the focus of policymakers has tended to be on ‘operational carbon’: the emissions created during a structure’s operations and use phase. Emissions, such as embodied carbon, from other life-cycle phases are generally considered less important.371
As operational carbon has been reduced due to concerted policy efforts and broader shifts in the energy sector, however, embedded carbon has assumed greater relative importance in the total life cycle of building structures.372 In the past few years, global operations-related carbon emissions from buildings seem to have reduced, yet emissions from building construction have continued to grow.373 In the longer term, operational emissions are contingent on factors like the future energy mix and energy generating technology that are to some extent outside of the control of construction sector stakeholders.374
Figure 26: Share of emissions by factor, UK construction sector, 2008
— Source: Authors’ analysis of data from Department for Business Innovation & Skills (2010), Estimating the Amount of CO2 Emissions that the Construction Industry can influence, Supporting material for the Low-carbon Construction IGT Report, Autumn 2010, https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/31737/10-1316-estimating-co2-emissions-supporting-low-carbon-igt-report.pdf (accessed 11 Jan. 2018).
Note: For assumptions and caveats used in calculations, refer to original source.
Note: For assumptions and caveats used in calculations, refer to original source.
Figure 26: Share of emissions by factor, UK construction sector, 2008
Note: For assumptions and caveats used in calculations, refer to original source.
Decarbonization in the built environment will therefore require disruptive innovation all along the supply chain, targeting the embodied carbon of building materials as well as emissions from the construction, use and end-of-first-life phases. Policymakers’ short-term focus on operational carbon, important though it is for efficiency measures in buildings, should not be an excuse for delaying action in these other areas.
Design
The design and planning stage has a profound impact on emissions from the sector. Section 3.4 discusses the importance of material selection for emissions, but this section considers the potential for design to reduce the amount of building materials, including concrete, required.
Key decisions include:
- Designing components to fulfil their function using less material. ‘Topology optimization’ is design aimed at optimizing material use within a given shape.375 This entails, for example, designing the shape of a beam so that material is only placed where it is necessary to carry out its function.376 Design principles from Gothic cathedrals have been used to design modern concrete floors that are 2 cm thick and 70 per cent lighter than their conventional counterparts.377
- Designing components for modularity and disassembly. Designing a building from prefabricated components that are assembled on site has benefits all along the value chain. Modularity can halve the duration of the construction process, as well as reduce energy consumption and labour costs.378 A modular building can be more easily retrofitted, and its disassembly at end of first life produces less waste and uses less energy.379
- Designing buildings to last longer and be more adaptable. A ‘long life, loose fit’ approach consists of designing a building to be flexible but also to have the structural durability to support many alternative functions over the course of its lifetime.380 Taller walls and more space are key to ensuring a long life and extending the usefulness of buildings.
Computer software is also transforming design methods.381 In combination with BIM, virtual reality and augmented reality are transforming the ways in which architects, engineers and clients can engage with a new design, allowing them to explore how a space feels in simulated walk-throughs and get a much more accurate view of a building before construction.382 Constraints with such approaches include the cost of specialized software, the additional time taken to approach design in a different way, and potential complications over the client brief and the budget. There is also currently a skills shortage: competent building information modellers are scarce.383
Design in different parts of the built environment has to be ‘joined up’ if problematic trade-offs are to be avoided
Design in different parts of the built environment has to be ‘joined up’ – with decisions in one area complementing, anticipating or integrated with those in others – if problematic trade-offs are to be avoided. Reducing the amount of materials used can, for example, result in less resilient and less robust structures. A building in which material efficiency has been prioritized may also be less easily adapted later on. For example, the shallow floor-to-ceiling height of many 1960s office blocks was advanced in terms of material efficiency, but this is now making them difficult to adapt. Currently, modularity often relies on less resilient materials; even if a building can be adapted, it might not have the resilience to support further use in the future. Architects and structural engineers are actively seeking ways to balance these different considerations to come up with optimal, sustainable designs.384
Material supply chain
Innovations in building materials that could change the carbon content of buildings and structures can be separated into three broad areas.
First, it is possible to substitute traditional building materials – concrete, steel and reinforced concrete – with lower-carbon, often bio-based, alternatives. Substitutability depends on the type of end use. More alternative materials are available for housing construction than for infrastructure projects.385 Depending on location, the density of structures and the required performance, bio-based alternatives to concrete include wood, hempcrete, timbercrete, straw bales, rammed earth, mycelium and bioMASON (which uses bacteria to grow cement to make bricks).386 A recent report also draws attention to the potential for the use of organic waste in construction.387
Wood currently seems to be the most versatile of these materials. Cross-laminated timber has been used in place of concrete and steel in structural floor and wall elements of buildings.388 However, commercial timber can itself be energy-intensive to produce, as it has to be dried in kilns;389 moreover, in many countries the availability of timber is restricted by land-use constraints. Where appropriate, however, using timber from sustainably managed farms could become an increasingly attractive option, especially given the potential for wood to lock in CO2 for decades, if not longer.390
The second area of innovation involves enhancing the properties of traditional building materials to lower the amount of materials needed and extend the durability of buildings. It includes developing ways to increase the strength of concrete, speed up hardening times, enable the transmission of light,391 and improve flexibility through nanoscience.392 Luminescent concrete has been used in the Netherlands to light roads and structures at night, cutting down on the need for electric lighting.393 Self-repairing or ‘self-healing’ concrete has been developed to increase the lifespan of concrete,394 with the potential to reduce lifetime operational costs by up to 50 per cent.395 HeidelbergCement is piloting a concrete that could store thermal energy from solar panels.396 Photocatalytic concrete – which decomposes airborne pollutants – has been trialled as a means of abating air pollution.397
Finally, innovators have explored new ways of combining materials. Using carbon-fibre composites instead of steel reinforcements, for example, reduces the amount of steel and concrete needed for a given building.398 Research around cement and concrete nanocomposites seeks to enhance the strength and durability characteristics of these materials.399 There has also been an increase in hybrid engineered timber/steel structures. These approaches have the potential to displace concrete use in conventional composite construction, particularly for multi-storey buildings, an area in which timber has featured little to date.400 These examples highlight the importance of thinking ‘across materials’ – i.e. not just thinking about ‘steel’ or ‘concrete’ or ‘timber’ in isolation but thinking about how these materials can be combined – to find innovative solutions.
Beyond the selection and combination of materials, there is a range of opportunities around their fabrication and delivery. Prefabrication, for example, could have a large impact on resource use in the cement and concrete sector.401 Historically, ready-mixed concrete has dominated the market. Precast concrete is mostly used in public-sector projects, due to its limitations for complex projects, the transport and storage costs involved, and the need for additional training of construction workers. However, the market share of precast concrete is increasing as developers recognize its potential benefits. These include material and process efficiency, cost effectiveness and sustainability.402
In time, 3D printing may lower costs of production, particularly in remote locations,403 and allow for more precision and efficiency in the application of materials, potentially lowering demand for them.404 Although the technology is still at an early stage of deployment, a Chinese company, Winsun, has successfully printed residential houses using a special ‘ink’ made of cement, sand, fibre and a proprietary additive.405
Construction processes
Some of the biggest changes may occur in construction. Compared with other parts of the value chain, it includes the largest number of low-skilled actors and is currently the most fragmented.406 It is potentially the area with the largest social and political implications in terms of jobs losses.407
Potential disruption can be broken into three types of changes around how construction processes are managed and monitored:
- On-site automation is already being used for complex tasks such as excavating construction sites, increasing efficiency and lowering production costs.408 Technological advances in intelligent machines are speeding up this trend. They are allowing increasingly complex tasks to be carried out by machines, monitored by human operators.
- Embedded sensors, mobile platforms and drones can be used to monitor projects, track assets and deliver real-time information to construction sites so that builders can make informed decisions about progress on projects and avoid mistakes or delays.409 In the context of concrete, these technologies could facilitate the tracking of usage, help users optimize application, and inform builders when concrete slabs or columns have reached the required strength.410
- Augmented-reality and mobile interfaces can be used to train builders on site, communicate with them and transmit important data to them during the performance of complex tasks.411 Providing visual instructions to workers mixing and pouring concrete, for instance, may improve the efficiency of application and facilitate the use of more novel cements in concrete mixes.
Operations and use
A huge opportunity to reduce material consumption lies in simply maintaining buildings for their full design life
A huge opportunity to reduce material consumption lies in simply maintaining buildings for their full design life. Building lifespans vary considerably between countries and applications.412 Residential and office buildings are generally expected to last 100 years, while commercial buildings are often designed to last 50 years but on average are replaced after only 25.413 Paradoxically, even as technical ability has increased, there has been a steady decline in the length of buildings’ operational lifespans.414
Connectivity, embedded sensors, intelligent machines and data analytics are enabling a host of changes in how buildings are managed, which can extend their useful lifetimes.415 Drones and robots can provide maintenance and retrofitting services.416 Sensors embedded throughout a building can deliver data to a central management system, reporting on structural integrity, energy use and operational health to raise issues as they crop up, such as the need to replace or refurbish a particular component.417
BIM may allow facilities managers to be involved at an earlier stage of the building planning process, so that they can influence the design and construction. At the end of a project, the BIM model can be handed over to the facilities manager, tenants, service agents and maintenance personnel, giving them access to details on materials.418 BIM can also ensure more accurate and timely maintenance or retrofit projects. Robotics companies are combining machine vision with BIM systems to retrofit insulation.419
However, insufficient durability is rarely the reason for replacing a building at least in industrialized countries. Other factors, typically financial, aesthetic and practical, drive most current demolition work.420 In the UK, for example, new construction is exempt from VAT while reuse and adaptation are often regarded as riskier and less desirable options.421
The challenge of extending the life of buildings is, therefore, about making them more adaptable and flexible as well as more durable – along the lines of the ‘long life, loose fit’ design approach highlighted above. Through smart design and use of materials, a building core can deliver a high-performance, low-carbon structure that is flexible enough to accommodate future tastes and requirements.
The shift towards shared and multiple-use infrastructure, often facilitated by digital technologies,422 could alter how many new buildings have to be built. During the 2016 Olympics in Rio de Janeiro, the online property-rental service Airbnb housed around 85,000 visitors in other peoples’ homes. Without the service, the city would have needed to build another 257 hotels,423 with roughly 3 million tonnes of concrete needed for the foundations alone.424
End of first life
Beyond how buildings and structures are designed, built and maintained, there are opportunities to better manage them when they reach the end of the initial useful lifespan envisaged in their design – as part of a broader shift to a circular economy. A circular economy is one ‘in which products are recycled, repaired or reused rather than thrown away, and in which waste from one process becomes an input into other processes’.425
Reusing concrete has multiple benefits: it reduces construction costs, volumes of new cement used, and construction and demolition waste
Reusing concrete, for example, has multiple benefits: it reduces construction costs, volumes of new cement used, and construction and demolition waste.426 There are different ways to reuse concrete. Reusing a whole frame in situ is increasingly common in the UK, and more carbon-efficient than removal of parts for use elsewhere.427 Moreover, the use of parts of a building elsewhere is often limited to precast concrete and modular components such as panels or slabs, as opposed to concrete that is cast on site.428 Precast concrete tends to be used in mass housing developments, where a large number of buildings need to be constructed in a short time at low cost.429 Mature economies may have valuable reuse potential embedded in their existing housing stock.
There has been growing interest around concrete ‘recycling’.430 Concrete structures can be broken down into aggregate and mixed back into new concrete. This type of recovered concrete is mostly used for roadworks, a lower-quality application.431 Such recycling can reduce the amount of virgin aggregate needed (and therefore the environmental costs of mining and transporting it), and it reduces the amount of waste materials in landfill. A large-scale renovation project in Paris recycled concrete from the building being renovated to achieve a 16 per cent reduction in the carbon intensity of the concrete aggregate used.432 Crushed concrete aggregate also carbonates, absorbing CO2. Optimizing this absorption by establishing global best practice for the demolition and storage of concrete could further reduce levels of embodied carbon.433 More recently, there has been excitement about ‘smart crushers’ that can crush and grind the cured cement elements of concrete, leaving sand and gravel intact.434
However, there are limits to the overall environmental benefits of recycling concrete. First, if the original concrete is of a low grade, this needs to be compensated for by mixing it with stronger cement. This would be the case for many buildings currently being demolished in China. Second, processing recycled concrete is more energy-intensive than processing virgin aggregate, as it requires decontamination.435 Third, transporting recycled concrete adds to the potential environmental cost, so recycled concrete preferably needs to be sourced close to the construction site where it will be used (although electrified transport could address this problem). Finally, current levels of recycling are low, although they vary geographically (roughly 28 per cent of the UK aggregate market is supplied from secondary and recycled sources).436 A plan to build a skyscraper out of recycled aggregate in Australia failed because not enough good-quality recycled aggregate could be found.437
4.3 Harnessing disruptive opportunities
Many doubt that the cement and concrete sector is susceptible to the kind of disruption that has been seen in many other parts of the economy over the past two decades. However, as this chapter has indicated, many opportunities are now opening up. Profound changes are under way that are putting new demands on the urban environment and creating new expectations of it. Especially in cities that are still rapidly growing, dramatic changes could emerge faster than currently anticipated. A suite of disruptive innovations is emerging in the sector that may transform the carbon content of buildings and structures, as well as the emissions produced over their lifetimes. Figure 27 summarizes these different areas of innovation along the value chain.
Figure 27: Disruptive innovation along the construction value chain
— Source: Authors’ own analysis.
Figure 27: Disruptive innovation along the construction value chain
Managing trade-offs
Many of the options highlighted in this chapter are complementary. Emerging approaches to design – e.g. topology optimization – are facilitated by the availability of novel, high-strength and flexible materials.438 3D printing has opened up the range of shapes available to architects and engineers.439 A shift towards prefabrication could help catalyse the move towards automation, as machines work best with standardized components and processes. In combination with modularity and prefabricated components, automation can already be applied to assembly and disassembly processes.440 In addition, increased use of information technology such as radio tags on site could make automation more flexible: reducing the need to standardize component sizes if there is less risk of pieces being placed or installed incorrectly.441
In some cases, however, solutions might work against each other. The use of some composite materials reduces the potential for disassembly and recycling. The use of standardized components on which prefabrication often depends may conflict with the goal of improving material efficiency. Lowering embodied carbon could increase operational carbon, depending on the building material chosen. Stakeholders in the cement and concrete sector often emphasize that the high thermal mass of concrete can increase the energy efficiency of buildings; they query whether reducing concrete use would not raise operational emissions from heating and cooling.442
Digital tools such as BIM may have an important role to play in managing and balancing the factors that will inform these different decisions, especially as the best course of action will be highly site-, geography- and project-specific. In some cases, using precast concrete for a modular building that will be adapted and changed over the course of its life will make sense. In others, the emphasis might be on ‘long life, loose fit’, with a composite material core that is expected to remain in place and an outer shell that can be adapted.
Implications for the cement and concrete sector
While the focus of this chapter has been largely on lowering the carbon content of buildings and structures as well as their emissions over time, doing so can sometimes result in reduced concrete use. Table 6 summarizes the ways in which the disruptive changes described could have an impact on demand for concrete (and therefore cement).
Table 6: Potential effects of changes in the construction sector on demand for cement and concrete
|
Disruptive innovation/shift |
Effect on demand for cement and concrete |
|---|---|
|
Advanced concrete |
Unclear: In theory, potentially less concrete will be needed in applications due to higher strength and other enhanced qualities. In practice, even in cases where high-strength concrete is used, more concrete is still applied than would be needed. |
|
Composite materials |
Unclear: It is too early to tell whether composites will reduce demand – and carbon mitigation will depend on the type of composite applied – but there are strong potential gains from certain types. More research is needed on nanocomposites. |
|
Alternative materials |
Lower demand: Shifting to alternative materials would decrease demand, but a degree of uncertainty exists about the scale of likely replacement given concerns about material availability and the properties of alternative materials and their suitability for different applications. |
|
Smart and intelligent materials |
Unclear: It is too early to tell whether smart materials will have an impact on the overall amount of concrete needed. Some smart concretes may increase demand, as they may allow concrete to be used in applications to which it was not previously suited. |
|
Modular and prefabricated design and construction |
Lower demand: Modular design and prefabricated/precast production has been shown to increase the efficiency of application, reduce waste and facilitate reuse of components. |
|
Topology optimization |
Lower demand: By definition, topology optimization should reduce demand for building materials, including concrete. |
|
Building information modelling |
Unclear: BIM could facilitate experimentation with novel cements and help the communication of decisions around reducing concrete use, but it largely acts as a facilitative tool for these activities. |
|
Big data and analytics |
Unclear: Although big data and analytics may help the industry to come up with optimized mixes and identify new compositions and nanocomposites, the likely impact on overall concrete use is still unclear. |
|
Sensing and monitoring |
Unclear: Sensing and monitoring may help to reduce concrete overuse in application and extend the useful lifetimes of buildings, thereby lowering demand, but it is still too early to tell. |
|
Virtual reality, augmented reality and simulation |
Unclear: Augmented reality, in particular, may help to improve efficiency in the application of concrete on site by providing workers with real-time information and guidance on the process, but it is still too early to tell whether this will be practical. |
|
Automation and AI |
Unclear: Although automation should increase efficiency and reduce wastage and errors in concrete application, the potential increase in productivity arising from increased automation could also lead to even more construction on a global scale, thereby increasing concrete demand. |
|
3D scanning and printing |
Unclear: 3D printing of buildings could increase material efficiency, but it is still too early to tell whether this will be a scalable opportunity beyond niche applications. |
|
Shared/multiple-use infrastructure |
Lower demand: Sharing buildings and widening their range of use should decrease the overall number of buildings needed, thereby reducing concrete demand. |
|
Circular economy |
Lower demand: An increased emphasis on reducing concrete use, and reusing and recycling concrete – including enhanced technical opportunities around recycling – should reduce demand for virgin cements and aggregates. |
Source: Authors’ own analysis, expanding on Buenfeld, N. (2016), ‘Low-carbon innovation in cement and concrete’, presentation given at a Chatham House roundtable on Low Carbon Innovation in Cement and Concrete, 12 May 2017.
In the cement and concrete sector, there is still a strong perception that most innovations are unlikely to significantly alter global concrete demand. Today, their effects are highly uncertain, and they can be expected to be context-dependent and to vary in scalability. Yet in many ways it would be surprising if the cement and concrete sector did not undergo major changes in the coming decades. Companies may wish to assess their readiness for these trends more systematically. Regardless of policy incentives related to climate change, broader trends in the built environment could prove highly disruptive. This points to the need for a wide range of stakeholders to think more carefully about disruption scenarios, and to test the assumptions used in cement modelling exercises.
Supporting low-carbon disruption
Like the cement and concrete sector, the construction sector is considered conservative and slow to change.443 Although many of the solutions discussed above are already used in high-value construction projects, several barriers stand in the way of scaling them up.
The skills and training needed to roll out digital and other technologies are an important consideration.444 In Europe, the construction sector is already suffering from a serious skills shortage and is struggling to deliver widespread training even on simple processes.445 Given the size and age of the workforce, there is a question over how quickly innovative technologies can be widely adopted.
Moreover, there is likely to be resistance to some of the technological changes described above. For example, the social impacts from automation may slow down the construction sector’s adoption of certain technologies, while concerns about a lack of individualization in housing developments and, in some locations, a poor image may present challenges to greater use of prefabricated components and buildings.446
Tailoring disruption to geographic contexts
It is beyond the scope of this report to examine in detail the policy frameworks and financial incentives needed to promote a sustainable, disruptive shift in the built environment. Key areas for consideration would include: changes to planning policies, and the financial structures around procurement, to encourage innovative approaches to design and procurement and adaptive reuse of existing structures; incentivizing the retention of existing structures where possible through, for example, tax reform; investment in training to address the digital skills gap; and the provision of de-risking mechanisms and financial support to encourage the use of new technologies and help to cover their cost.
As with policy encouragement for lower-carbon materials (see Section 3.4), it will be important to avoid being too prescriptive and to allow for mixing and matching the right technology solutions to fit the given context. Moreover, these policy frameworks should be tailored to the needs of different regions and to the specific potential for disruption in each of them. Eighty per cent of new construction in the period to 2060 is projected to be in non-OECD countries.447 In some countries, growth will occur within a very short time frame: for example, 45 per cent of the projected increase in floor area in China by 2060 is expected to be completed by 2030.448 By contrast, 65 per cent of the forecast building stock in OECD countries in 2060 is already standing today.449
As emphasized in Chapter 2, there are many regional differences in material supply chains. This affects the potential impact and penetration of new technologies. In the UK, for example, the ready-mixed-concrete industry uses automated supply, while in India 90 per cent of the concrete used is still bagged.450
This points to a need for different pathways to lowering the carbon content and impacts of the built environment in different regions.451 Countries in which the majority of new construction is expected to happen – including China, India and Indonesia – should leverage the disruptive opportunities that are suited to developing a low-carbon building stock from scratch. These opportunities include lowering embodied carbon. Meanwhile, in more mature building sectors in Europe and North America, the focus should be on large-scale retrofitting of buildings and structures to lower their operational carbon, as well as on scaling up adaptive reuse and recycling of buildings at the end of first life.
347 UN Environment and International Energy Agency (2017), Global Status Report 2017.
348 The New Climate Economy (2016), The Sustainable Infrastructure Imperative.
349 Weber, V. (2017), ‘How automation and technology will change the buildings we live in’, World Economic Forum, 10 August 2017, https://www.weforum.org/agenda/2017/08/how-automation-and-connected-technology-will-change-the-buildings-we-live-in/ (accessed 18 Oct. 2017).
350 McKinsey & Company (2012), Mobility of the future: Opportunities for automotive OEMs, https://www.mckinsey.com/~/media/mckinsey/dotcom/client_service/automotive%20and%20assembly/pdfs/mobility_of_the_future_brochure.ashx (accessed 19 Oct. 2017).
351 Granoff, I., Hogarth, J. R. and Miller, A. (2016). ‘Nested barriers to low-carbon infrastructure investment’, Nature Climate Change, 6: pp. 1065–1071, doi: 10.1038/nclimate3142 (accessed 6 Jun. 2017).
352 Lovins, A. B. (2017), ‘Disruptive energy futures’, presentation at Chatham House, 8 June 2017.
353 The New Climate Economy (2016), The Sustainable Infrastructure Imperative.
354 Norton, P. (2008), Fighting Traffic: The Dawn of the Motor Age in the American City, London: MIT press.
355 Lim, L. (2013), ‘Five Years after a Quake, Chinese Cite Shoddy Reconstruction’, NPR, 13 May 2013, http://www.npr.org/sections/parallels/2013/05/14/183635289/Five-Years-After-A-Quake-Chinese-Cite-Shoddy-Reconstruction (accessed 19 Oct. 2017); Schiavenza, M. (2013), ‘Why Earthquakes in China Are So damaging’, The Atlantic, 25 July 2013, https://www.theatlantic.com/china/archive/2013/07/why-earthquakes-in-china-are-so-damaging/278092/ (accessed 19 Oct. 2017); Hooper, J. (2016), ‘Italy earthquake throws spotlight on lax construction laws’, Guardian, 24 August 2016, https://www.theguardian.com/world/2016/aug/24/italy-earthquake-throws-spotlight-on-lax-construction-laws (accessed 19 Oct. 2017).
356 Booth, R. (2017), ‘Combustible cladding found on 120 tower blocks so far, says PM’, Guardian, 28 June 2017, https://www.theguardian.com/politics/2017/jun/28/combustible-cladding-found-on-120-tower-blocks-so-far-says-pm-pmqs-grenfell-tower (accessed 19 Oct. 2017).
357 IBM (undated), ‘Outthink urban planning’, https://www.ibm.com/events/ke/en/ted-outthink-urban.html [URL no longer works] (accessed 18 Oct. 2017).
358 Jefferies, D. (2015), ‘How the internet of things could revolutionise council services’, Guardian, 31 March 2015, https://www.theguardian.com/public-leaders-network/2015/mar/31/internet-of-things-revolutionise-council-services (accessed 18 Oct. 2017).
359 Weber (2017), ‘How automation and technology will change the buildings we live in’.
360 Ibid.
361 External workshop participant.
362 International Energy Agency (2017), Energy Technology Perspectives 2017.
363 Ibid.
364 The New Climate Economy (2016), The Sustainable Infrastructure Imperative.
365 Design Exchange (2016), ‘Can 4D Printing Be A Game Changer In Architecture?’, 25 April 2016, http://www.demagazine.co.uk/architecture/can-4d-printing-be-a-game-changer-in-architecture (accessed 18 Oct. 2017).
366 CSIRO (2015), ‘Climate impacts on concrete infrastructure’, case study, 26 February 2015, https://www.csiro.au/en/Research/LWF/Areas/Resilient-cities-21C/Climate-adaptation/Concrete (accessed 10 May 2017).
367 Wang, X., Nguyen, M., Stewart, M. G., Syme, M. and Leitch, A. (2010), Analysis of Climate Change Impacts on the Deterioration of Concrete Infrastructure – Part 3: Case Studies of Concrete Deterioration and Adaptation, Canberra: CSIRO, https://publications.csiro.au/rpr/download?pid=csiro:EP104734&dsid=DS5 (accessed 11 Jun. 2017).
368 Metsä Group (2017), ‘Construction is the best use of wood’, http://www.metsagroup.com/en/media/Pages/Case-Wood-building-a-carbon-sink.aspx (accessed 18 Oct. 2017).
369 Deich, N. (2014), ‘Buildings: an untapped source for Greenhouse Gas Removal’, Virgin Earth Challenge, 22 July 2014, http://www.virginearth.com/2014/07/buildings-an-untapped-source-for-greenhouse-gas-removal/ (accessed 18 Oct. 2014).
370 MIT Building Tech (2017), DeQo Database of embodied Quantity outputs, https://www.carbondeqo.com/ (accessed 1 Feb. 2018).
371 Pöyry, A., Saeynaejoki, A., Heinonen, J., Junnonen, J. M. and Junnilla, S. (2015), ‘Embodied and construction phase greenhouse gas emissions of a low-energy residential building’, Procedia Economics and Finance, 21: pp. 355–365, doi:10.1016/S2212-5671(15)00187-2 (accessed 12 Jan. 2018); UN Environment and International Energy Agency (2017), Global Status Report 2017; Laski, J. and Burrows, V. (2017), From Thousands to Billions: Coordinated Action towards 100 % Net Zero Carbon Buildings by 2050, London: UK Green Building Council.
372 MIT Building Tech (2017), DeQo Database of embodied Quantity outputs.
373 UN Environment and International Energy Agency (2017), Global Status Report 2017.
374 Pöyry et al. (2015), ‘Embodied and construction phase greenhouse gas emissions of a low-energy residential building’.
375 Bendsøe, M. P. and Sigmund, O (2004), Topology optimization – theory, methods and applications, Berlin: Springer-Verlag.
376 Moynihan, M. C. and Allwood, J. M. (2014), ‘Utilization of structural steel in buildings’, Proceedings of the Royal Society A, doi: 10.1098/rspa.2014.0170 (accessed 12 Jan. 2018).
377 Rüegg, P. (2017), ‘Gothic cathedrals inspire very thin concrete floors’, Futurity, 12 April 2017, http://www.futurity.org/concrete-floors-1399952-2/ (accessed 11 Dec. 2017).
378 Designing Buildings Wiki (2016), ‘Modular vs traditional construction’, 29 June 2016, https://www.designingbuildings.co.uk/wiki/Modular_vs_traditional_construction (accessed 9 May 2017).
379 Rauland, V. and Newman, P. (2015), Decarbonising Cities: Mainstreaming Low-carbon Urban Development, Cham: Springer International Publishing.
380 Langston, C. (2014), ‘Measuring Good Architecture: Long life, loose fit, low energy’, European Journal of Sustainable Development, 3(4): pp. 163–174, doi: 10.14207/ejsd.2014.v3n4p163 (accessed 2 Feb. 2018).
381 University of Liverpool (2013), ‘Minimising Material Waste by Utilising BIM and Set-based Design in the Structural Design of Reinforced Concrete Slabs’, https://livrepository.liverpool.ac.uk/2007735/1/C2013.02%20Minimising%20Material%20Waste%20by%20Utilisation%20of%20BIM.pdf (accessed 2 Aug. 2017).
382 Arch Daily (2017), ‘Will Virtual Reality Transform the Way Architects Design?’, 30 May 2017, http://www.archdaily.com/872011/will-virtual-reality-transform-the-way-architects-design (accessed 15 Jun. 2017).
383 Azhar, Hein and Sketo (2014), ‘Building Information Modeling (BIM)’.
384 University of Liverpool (2013), ‘Minimising Material Waste by Utilising BIM’.
385 Zerelli, N., Korner, C., Putz, W., Krückeberg, L. and Willemeit, T. (2016), Architecture Activism, Basel: Birkhäuser De Gruyter, p. 65.
386 bioMASON (2018), ‘Technology’, https://biomason.com/technology/ (accessed 25 Feb. 2018).
387 Arup (2017), The Urban Bio-Loop: Growing, Making and Regenerating, Milan: Arup.
388 Harris, R. (2015), ‘Cross laminated timber’, in Ansell, M. (ed.) (2015), Wood Composites, Cambridge: Woodhead Publishing Limited.
389 Allwood et al. (2012), Sustainable materials: with both eyes open.
390 Metsä Group (2017), ‘Construction is the best use of wood’.
391 Dogne, N. and Choudhary, A. (2014), ‘Smart Construction Materials & Techniques’, Conference Paper for National Conference on Alternative & Innovative Construction Materials and Techniques, https://www.researchgate.net/publication/297167802_SMART_CONSTRUCTION_MATERIALS_TECHNIQUES (accessed 11 May 2017).
392 Stauffer, N. W. (2016), ‘Designing climate-friendly concrete, from the nanoscale up’, MIT News, 21 July 2016, http://news.mit.edu/2016/designing-climate-friendly-concrete-at-the-nanoscale-0721 (accessed 25 Feb. 2018). Lafarge developed Ductal concretes with high compressive and flexural strength. Dogne and Choudhary (2014), ‘Smart Construction Materials & Techniques’.
393 Carreño, B. (2016), ‘Glow-Hard: Luminous Cement Could Light Roads, Structures’, Scientific American, 16 June 2016, https://www.scientificamerican.com/article/glow-hard-luminous-cement-could-light-roads-structures/ (accessed 17 Oct. 2017).
394 Spinks, R. (2015), ‘The self-healing concrete that can fix its own cracks’, Guardian, 29 June 2015, https://www.theguardian.com/sustainable-business/2015/jun/29/the-self-healing-concrete-that-can-fix-its-own-cracks (accessed 17 Jul. 2017); Calkins (2017), ‘Concrete Minus Carbon’.
395 World Economic Forum and the Boston Consulting Group (2016), Shaping the Future of Construction.
396 Energy Matters (2015), ‘Energy Storage – The Concrete Battery’, 29 June 2015, https://www.energymatters.com.au/renewable-news/concrete-battery-storage-em4894/ (accessed 17 Oct. 2017).
397 Calkins (2017), ‘Concrete Minus Carbon’.
398 Reute, A. (2017), ‘Eine neue Art des Bauens’ [A new way of building], C³ – Carbon Concrete Composite e. V., 9 February 2015, https://www.bauen-neu-denken.de/eine-neue-art-des-bauens/ (accessed 17 Oct. 2017).
399 Chuah, S., Pan, Z., Sanjayan, J. G., Wang, C. M. and Duan, W. H. (2014), ‘Nano reinforced cement and concrete composites and new perspective from graphene oxide’, Construction and Building Materials, 73: pp. 113–124, doi: 10.1016/j.conbuildmat.2014.09.040 (accessed 17 Oct. 2017).
400 Cotgrave, A. and Riley, M. (2013), Total Sustainability in the Built Environment, Basingstoke: Palgrave Macmillan.
401 World Economic Forum and the Boston Consulting Group (2016), Shaping the Future of Construction.
402 National Precast Concrete Association (2010), ‘Precast Concrete Manufacturing and the Environment’, 28 July 2010, http://precast.org/2010/07/precast-concrete-manufacturing-and-the-environment/ (accessed 18 Oct. 2017).
403 Becker, R. and Vincent, J. (2017), ‘Autonomous robot 3D printers like this could help build homes for us on other planets’, The Verge, 27 April 2017, https://www.theverge.com/2017/4/27/15447578/autonomous-robot-3d-printers-mit-homes-planets (accessed 19 Oct. 2017).
404 Gosselin, C., Duballet, R., Roux, Ph., Gaudillière, N., Dirrenberger, J. and Morel, Ph. (2016), ‘Large-scale 3D printing of ultra-high performance concrete – a new processing route for architects and builders’, Materials and Design, 100: pp. 102–109, https://www.researchgate.net/profile/Justin_Dirrenberger/publication/299444698_Large-scale_3D_printing_of_ultra-high_performance_concrete_-_a_new_processing_route_for_architects_and_builders/links/57018f0908ae650a64f8c3fc.pdf (accessed 10 Jul. 2017).
405 World Economic Forum and the Boston Consulting Group (2016), Shaping the Future of Construction.
406 Proverbs, D. G., Holt, G. D. and Cheok, H. Y. (2000), ‘Construction industry problems: the views of UK construction directors’, In: Akintoye A, (ed.), 16th Annual ARCOM Conference, 6–8 September 2000, Glasgow Caledonian University. Association of Researchers in Construction Management, 1: pp. 73–81, http://www.arcom.ac.uk/-docs/proceedings/ar2000-073-081_Proverbs_Holt_and_Cheok.pdf (accessed 19 Oct. 2017).
407 Rotman, D. (2013), ‘How technology is destroying jobs’, MIT Technology Review, 12 June 2013, https://www.technologyreview.com/s/515926/how-technology-is-destroying-jobs/ (accessed 19 Oct. 2017); Elliott, L. (2017), ‘Millions of UK workers at risk of being replaced by robots, study says’, MIT Technology Review, 24 March 2017, https://www.theguardian.com/technology/2017/mar/24/millions-uk-workers-risk-replaced-robots-study-warns (accessed 19 Oct. 2017).
408 Grayson, W. (2015), ‘With drones and driverless dozers, Komatsu to begin leasing automated construction fleets’, Equipment World, 26 January 2015, https://www.equipmentworld.com/with-drones-and-driverless-dozers-komatsu-to-begin-leasing-automated-construction-fleets/ (accessed 12 Nov. 2016).
409 Ikonen, J., Knutas, A., Haemailaeinen, H., Ihonen, M., Porras, J. and Kallonen, T. (2013), ‘Use of embedded RFID tags in concrete element supply chains’, Journal of Information Technology in Construction, 18: pp. 119–147, http://www.itcon.org/2013/7 (accessed 2 Feb. 2018).
410 Converge (2018), How it works, https://www.converge.io/product (accessed 25 Feb. 2018).
411 World Economic Forum and the Boston Consulting Group (2016), Shaping the Future of Construction.
412 Celadyn, W. (2014), ‘Durability of Buildings and Sustainable Architecture’, Technical Transactions Architecture,7–A: pp. 17–26, https://suw.biblos.pk.edu.pl/downloadResource&mId=1275984 (accessed 23 Feb. 2018).
413 Ibid.
414 Pomponi, F. and Moncaster, A. (2016), ‘Circular economy for the built environment: A research framework’, Journal of Cleaner Production, 143: pp. 710–718, doi: 10.1016/j.jclepro.2016.12.055 (accessed 10 Jun. 2017).
415 World Economic Forum and the Boston Consulting Group (2016), Shaping the Future of Construction.
416 Lavars, N. (2015), ‘How drones are poised to build the cities of tomorrow’, New Atlas, 2 March 2015, https://newatlas.com/drones-building-construction-industry/36306/ (accessed 19 Oct. 2017); Carr, D. (2015), ‘A robotic solution to a retrofit conundrum’, Building4Change, 9 June 2015, http://www.building4change.com/article.jsp?id=2653#.WeoGcFtSzcs (accessed 10 Oct. 2017).
417 Somwanshi, S. and Gawalwad, B. (2015), ‘Monitoring civil structures with a smart wireless sensor network’, International Journal of Engineering and Applied Sciences, 2(3): pp. 34–38, ISSN: 2394-3661 (accessed 18 Oct. 2017); Spencer, B. F., Ruiz-Sandoval, M. and Kurata, N. (2004), ‘Smart sensing technology: opportunities and challenges’, Structural Control Health Monitoring, 11: pp. 349–368, doi: 10.1002/stc.48 (accessed 18 Oct. 2017).
418 Azhar, Hein and Sketo (2014), ‘Building Information Modeling (BIM)’.
419 Building Products (undated), ‘Futuristic robot helps deliver construction service’, http://buildingproducts.co.uk/futuristic-robot-helps-deliver-construction-service/ (accessed 11 Dec. 2017).
420 Bullen, P. and Love, P. (2009), ‘Factors influencing the adaptive re-use of buildings’, Journal of Engineering, Design and Technology, 9(1): pp. 32–46, doi: 10.1108/17260531111121459 (accessed 23 Feb. 2018).
421 Gov.UK (2018), ‘VAT for builders’, https://www.gov.uk/vat-builders/new-homes (accessed 23 Feb. 2018).
422 Ernst & Young (2015), The rise of the sharing economy: The Indian landscape, October 2015, http://www.ey.com/Publication/vwLUAssets/ey-the-rise-of-the-sharing-economy/$FILE/ey-the-rise-of-the-sharing-economy.pdf (accessed 20 Oct. 2017).
423 World Economic Forum (2016), Understanding the Sharing Economy, http://www3.weforum.org/docs/WEF_Understanding_the_Sharing_Economy_report_2016.pdf (accessed 18 Oct. 2017); Lee, B. (2017), ‘Are we on the cusp of a demand revolution?’, Hoffmann Centre for Sustainable Resource Economy, 18 May 2017, https://hoffmanncentre.chathamhouse.org/article/are-we-on-the-cusp-of-a-demand-revolution/ (accessed 18 Oct. 2017).
424 Authors’ analysis based on estimate that 12,000 tonnes of concrete were needed for a hotel in Florida. Zaffiro-Kean, E. (2017), ‘24 million lbs. of concrete = 1 Daytona hotel foundation’, Daytona Beach News-Journal, 24 August 2017, http://www.news-journalonline.com/news/20170824/24-million-lbs-of-concrete—1-daytona-hotel-foundation (accessed 18 Oct. 2017).
425 Preston, F. and Lehne, J. (2017), A Wider Circle? The Circular Economy in Developing Countries, Briefing, London: Royal Institute of International Affairs, https://www.chathamhouse.org/publication/wider-circle-circular-economy-developing-countries (accessed 16 Apr. 2018).
426 Hradil, P., Talja, A., Wahlstroem, M., Huuhka, S., Lahnedisvu, J. and Pikkuvirta, J. (2014), Re-use of structural elements: Environmentally efficient recovery of building components, VTT Technical Research Centre of Finland Ltd, http://www.vtt.fi/inf/pdf/technology/2014/T200.pdf (accessed 23 Feb. 2018).
427 Mineral Products Association The Concrete Centre (undated), ‘Refurbishment, reuse and renewal’, https://www.concretecentre.com/Performance-Sustainability-(1)/Material-Effieciency/Refurbishment,-reuse-and-renewal.aspx (accessed 27 Mar. 2018).
428 Salama, W. (2017), ’Design of concrete buildings for disassembly: An explorative review’, International Journal of Sustainable Built Environment, 6: pp. 617–635, doi: 10.1016/j.ijsbe.2017.03.005 (accessed 23 Feb. 2018); Huuhka, S., Kaasalainen, T., Hakanen, J. H. and Lahdensivu, J. (2015), ‘Reusing concrete panels from buildings for building: Potential in Finnish 1970s mass housing’, Resources, Conservation and Recycling, 101: pp. 105–121, doi: 10.1016/j.resconrec.2015.05.017 (accessed 28 Feb. 2018).
429 Cement Manufacturers’ Association (2015), ‘Housing – Mass Housing and Technological Options’, http://www.cmaindia.org/industry/housing–mass-housing-and-technological-options.html (accessed 10 May 2017).
430 Fraile-Garcia, E., Ferreiro-Cabello, J., Lopez-Ochoa, L. M. and Lopez-Gonzalez, L. M. (2017), ‘Study of the Technical Feasibility of Increasing the Amount of Recycled Concrete Waste Used in Ready-Mix Concrete Production’, Materials, 10(7), doi: 10.3390/ma10070817 (accessed 23 Feb. 2018).
431 Tabsh, S. W. and Abdelfatah, A. S. (2008), ‘Influence of recycled concrete aggregates on strength properties of concrete’, Construction and Building Materials. 23: pp. 1163–1167, doi: 10.1016/j.conbuildmat.2008.06.007 (accessed 10 Jul. 2017); Cembureau (2016), Cement, concrete & the circular economy, Brussels: European Cement Association, https://cembureau.eu/media/1229/9062_cembureau_cementconcretecirculareconomy_coprocessing_2016-09-01-04.pdf (accessed 23 Feb. 2018).
432 UN Environment and International Energy Agency (2017), Global Status Report 2017.
433 Mineral Products Association (2016), Whole-life Carbon and Buildings: Concrete solutions for reducing embodied and operational CO2, https://www.concretecentre.com/Publications-Software/Publications/Whole-life-Carbon-and-Buildings.aspx (accessed 23 Feb. 2018).
434 De Ingenieur (2018), ‘Smart Crusher Saves Concrete and CO2’, 5 Jun. 2018, https://www.deingenieur.nl/artikel/smart-crusher-saves-concrete-and-co2 (accessed 7 Jun. 2018).
435 Scrivener, John and Gartner (2016), Eco-efficient cements.
436 UK data for 2015, Mineral Products Association (undated), ‘Aggregates’, http://www.mineralproducts.org/prod_agg_recy01.htm (accessed 23 Feb. 2018); World Business Council for Sustainable Development (2009), Recycling Concrete, https://www.wbcsdcement.org/pdf/CSI-RecyclingConcrete-Summary.pdf (accessed 23 Feb. 2018).
437 Internal workshop participant.
438 Immsider (2016), ‘Smart Materials: Neue Werkstoffe verändern das Design’ [Smart materials: new materials are changing design], 11 October 2016, http://www.immsider.de/2016/10/smart-materials-new-materials-are-changing-the-design-world/?lang=en (accessed 2 Mar. 2017).
439 Chalcraft, E. (2013), ‘How 3D printing will change architecture and construction’, Dezeen, 21 May 2013, https://www.dezeen.com/2013/05/21/3d-printing-architecture-print-shift/ (accessed 15 Jun. 2017); Winston, A. (2014), ‘Arup unveils its first 3D-printed structural steel building components’, Dezeen, 11 June 2014, https://www.dezeen.com/2014/06/11/arup-3d-printed-structural-steel-building-components/ (accessed 25 Feb. 2018).
440 Neelamkavil, J. (2009), ‘Automation in the prefab and modular construction industry’, 26th International Symposium on Automation and Robotics in Construction (ISARC 2009), https://www.irbnet.de/daten/iconda/CIB14850.pdf (accessed 18 Oct. 2017).
441 Moynihan and Allwood (2014), ‘Utilization of structural steel in buildings’.
442 Mineral Products Association (undated), ‘Low-carbon: concrete is essential to deliver thermal mass and energy efficiency’, https://www.concretecentre.com/This-Is-Concrete/Low-Carbon.aspx (accessed 23 Feb. 2018); Cembureau (undated), ‘Downstream’, ‘The Role of Cement in the 2050 Low Carbon Economy’, http://lowcarboneconomy.cembureau.eu/index.php?page=downstream-2 (accessed 23 Feb. 2018); European Concrete Platform ASBL (2007), Concrete for energy-efficient buildings: The benefits of thermal mass, Brussels: European Concrete Platform ASBL, https://www.theconcreteinitiative.eu/images/ECP_Documents/ConcreteForEnergyEfficientBuildings_EN.pdf (accessed 23 Feb. 2018).
443 Giesekam, Barrett and Taylor (2015), ‘Construction sector views on low-carbon building materials’; World Economic Forum and the Boston Consulting Group (2016), Shaping the Future of Construction.
444 McKinsey Global Institute (2017), Reinventing Construction.
445 European Commission (undated), European Construction Sector observatory: Improving the human capital basis, https://ec.europa.eu/docsroom/documents/26206/attachments/1/translations/en/renditions/native (accessed 23 Feb. 2018); European Commission (2017), European Construction Sector Observatory: Country profile Germany, March 2017, https://ec.europa.eu/docsroom/documents/23744/attachments/1/translations/en/renditions/pdf (accessed 23 Feb. 2018).
446 Gardiner, J. (2017), ‘Can prefab homes solve UK’s housing crisis?’, Guardian, 26 January 2017, https://www.theguardian.com/sustainable-business/2017/jan/26/prefab-homes-uk-housing-crisis-modular-offsite-construction-manchester-liverpool-energy-efficiency (accessed 23 Feb. 2018).
447 International Energy Agency (2017), Energy Technology Perspectives 2017, p. 125.
448 UN Environment and International Energy Agency (2017), Global Status Report 2017.
449 International Energy Agency (2017), Energy Technology Perspectives 2017, p. 125.
450 Scrivener, John and Gartner (2016), Eco-efficient cements.
451 UN Environment and International Energy Agency (2017), Global Status Report 2017.