Sustainable steel construction
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Sustainable development targets cannot be met without a fundamental change to the way...

Sustainable development targets cannot be met without a fundamental change to the way
in which buildings are constructed.

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  • 1. Sustainable steel construction Building a sustainable futureCare has been taken to ensure that thecontents of this publication are accurate,but Tata Steel Europe Limited and itssubsidiaries do not accept responsibility orliability for errors or information that is foundto be misleading.Corus and the BCSA care about theenvironment – this brochure is printed withbiodegradable vegetable inks and usingmaterial with at least 80% recycled content.Corus Long Products The British ConstructionalPO Box 1 Steelwork AssociationBrigg Road 4 Whitehall CourtScunthorpe WestminsterNorth Lincolnshire LondonDN16 1BP SW1A 2ESUnited Kingdom United KingdomT: +44 (0) 1724 404040 T: +44 (0) 20 7839 8566F: +44 (0) 1724 282040 F: +44 (0) 20 7976
  • 2. Staythorpe Power Station, Newark (photograph: Severfield-Reeve Structures Ltd)Contents The steel construction sector – introduction . . . 03 Steel sector commitments . . . . . . . . . . . . . . . . . 04 Steel: the ultimate sustainable material . . . . . . . 06 BCSA Sustainability Charter . . . . . . . . . . . . . . . 08 The steel Sustainable procurement . . . . . . . . . . . . . . . . . . 09 Delivering the triple bottom line . . . . . . . . . . . . . 10 Design guidance . . . . . . . . . . . . . . . . . . . . . . . . 12 construction sector Target Zero . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Sustainable champions for The steel sector – comprising the British Sustainability has what is often known the UK building industry Constructional Steelwork Association as a ‘triple bottom line’, comprising Mitigating climate change . . . . . . . . . . . . . . . . . 14 Buildings are responsible for almost half (BCSA), Corus and the Steel environmental, social and economic Construction Institute (SCI) – is delighted factors. Environmental issues receive the of the UK’s carbon emissions, half of its Thermal mass and CO2: facts and figures . . . . . 16 water consumption, around a third of its to be leading the way in developing a more sustainable construction industry most attention, but social and economic factors are also of vital importance, and landfill waste and a quarter of all raw for the UK. Our commitments range from this document sets out the benefits of Innovation in steel . . . . . . . . . . . . . . . . . . . . . . . 18 materials used in the economy. producing design guidance on creating steel to all three issues. It also underlines buildings that meet the Government’s the steel industry’s commitment to This means that the UK’s sustainable zero carbon objectives to researching the sustainable development, the unequalled development targets cannot be met environmental impact of steel in buildings sustainable benefits of steel as a building without a fundamental change to the way and developing products and processes material, the achievements of the sector in which buildings are constructed. The to reduce that impact. to date and its vision for the future. national targets for greenhouse gas emission reductions and the drive for buildings that generate zero carbon in operation present a huge challenge to the building industry – a challenge which the steel construction sector is playing a major part in overcoming. Lakeside Energy from Waste Plant, Colnbrook (photograph: Ros Orpin)02 03
  • 3. Steel sector Reducing the carbon footprint of buildings is set to remain a top commitments priority for the steel construction sector Sustainability is already high on the Looking to the future agenda for all companies involved in the Today, and for the years to come, construction sector. The importance of the steel construction sector is sustainability will only increase in the committed to: coming years as Government legislation comes into full force and the subject is • Working with Government to meet better understood thanks to continuing the objectives of its sustainable research and development. construction strategy The growing role of steel • Providing design guidance and The steel construction sector in the UK information that allows designers to wholeheartedly embraces the push create buildings which reduce the towards greater sustainability in whole-life costs and environmental construction. Steel itself is an inherently burdens associated with buildings sustainable building material and is destined to play a significant role in • Providing design guidance and helping the construction sector achieve information that allows designers to its ambitious sustainable objectives. create buildings that can achieve the highest BREEAM ratings and which meet Government aspirations for zero-carbon building operation • Developing patterns of sustainable procurement consistent with the requirements of emerging standards in this area • Continuing to invest in research and development to reduce the carbon footprint of its processes and products • Providing industrial companies in the sector with the means of improving the performance of their businesses through sustainable business practices • Giving specifiers and procurement agencies the opportunity to identify key supply chain partners that share a commitment to sustainable construction. Opposite page Lorem ipsum dolor sit amet, consectetuer adipiscing elit.04 Manchester Civil Justice Centre 19 05
  • 4. Steel:the ultimatesustainablematerialThe sustainable qualities of steel are built in to the Hafod Eryri, the Snowdon visitor centre, ismaterial. Simply choosing steel as a building material an exemplar in offsite construction (steelwork contractor: Evadx; photograph:enables specifiers to deliver unrivalled sustainability Ray Wood photography)performance – for life, and for all its subsequent lives. Manufactured from the most abundant are easily adaptable if the configuration in the construction process. fabrication phase can be recycled and Offsite construction – element on earth, iron, steel can be of the building needs to change. The Constructing a building from a used in the steelmaking process. Recycled content the sustainable choice recycled or reused endlessly without ability of steel to bridge long spans demounted structure is one of the detriment to its properties. Its superior means that steel buildings contain large most sustainable ways of creating Safe Recycled content is specified to strength-to-weight ratio means a little open-plan spaces which are easily a ‘new’ building. Industry surveys consistently The nature of the steel construction encourage recycling of materials steel goes a long way, giving architects reconfigured with partition walls. The demonstrate that steel is the safest process is the source of numerous complete flexibility to achieve their most steel frame itself can be adapted, with Fast construction material. Components are which would otherwise be sustainable benefits. All of the ambitious designs. Manufactured in a parts added or taken away, and its light The speed of steel construction has fabricated offsite in a safe, controlled disposed of. However, it is not a fabrication, testing and certification controlled factory environment, pre- weight means that extra floors can made it the framing material of choice factory environment. From here they are suitable driver for metals that are takes place in a safe, carefully engineered steel components are often be added without overloading for the UK construction sector. A shorter delivered to site and erected by a small already recovered and recycled delivered to site ready for rapid existing foundations. construction programme reduces number of skilled personnel. There is close to their maximum. Specifying controlled and monitored factory assembly, with no waste. disruption and disturbance around the minimal requirement for on-site cutting environment. Here, consistently high recycled content for steel does not Reusable site. Steel is relatively clean and quiet to or adjustment, and no need for the quality standards can be maintained Multicycling Because steel frames are essentially erect, and requires few site deliveries. time-consuming and potentially have any beneficial environmental and assured, with Steel can be reused repeatedly without a kit of parts, they can easily be Speed of construction delivers an hazardous shuttering and handling effect, but can distort the market each component manufactured ever losing its qualities as a building dismantled and reused. Bolted economic benefit too, which is operations associated with other and result in unnecessary transport to the exact specifications of material. This unique characteristic gives connections allow components to be fundamental to sustainable construction materials. costs and emissions. All steel is all steel a high value at all stages of its removed in prime condition and easily development. The shorter on-site period recyclable and will be multicycled each project. This leads to life cycle. The recovery infrastructure for reused either individually or en masse reduces the cost of preliminaries, Zero waste quicker, safer and more steel recycling is highly developed and as entire structures. It means that steel reduces the period of financing and When you specify steel for a building, many times without any artificial predictable on-site operations. highly efficient, and has been in place for components are perpetually reused in delivers a building that is operational you can rest assured that it is unlikely stimulus. decades. Current recovery rates from a continuous loop, and never sent faster – providing a quicker return from ever to become waste. Steel always has Offsite construction has clear demolition sites in the UK are 99 per to landfill. rent or sale. a value and is only ever sent to landfill as All new steel manufactured by environmental benefits, with cent for structural steelwork and 94 per a last resort. Waste generation is one of Corus has a significant recycled cent for all steel construction products – Demountable Manufactured the least sustainable aspects of on-site waste virtually eliminated content. The modern steelmaking figures that far exceed those for any Entire steel structures can be fully All steel components are manufactured construction. Choosing a steel-framed and fewer deliveries to site, cutting other construction material. dismantled and reconstructed in a in the controlled environment of a building is the simplest and most process requires the input of scrap carbon emissions associated with different location in a matter of days, fabrication workshop, where consistent effective way to reduce waste. Even and it is not possible to make steel transport. Steel construction has Adaptable without creating any dust and dirt, and structural elements with assured quality during steel manufacture and fabrication, without it. The average recycled always been carried out in this way, Significant environmental damage can very little noise. This demountable can be created to meet the specific any swarf or offcuts are recovered and content of structural steel used in be caused at the end of a building’s life capability is inherent in a steel building – requirements of each project. In this recycled in the steelmaking process. the UK is 60 per cent. making it an exemplar for when it has to be demolished and its it doesn’t need to be specially designed environment, steel parts can be easily sustainable offsite construction. materials scrapped. Steel-framed in and rarely requires any extra provision standardised, tested and certified. Any buildings, however, do not decay, and waste material produced during the06 07
  • 5. Cabot Circus Footbridge, Bristol, inconstruction (photograph: SH Structures) Vulcan House, Sheffield: a BREEAM Excellent-rated building Raw materials areBCSA Sustainability Sustainable responsibly sourced by Corus, and the company champions environmentally responsible procurement The BCSA’s pioneering Sustainability Charter setsCharter environmental objectives for its members and measures performance against key sustainability criteria practices throughout its supply chainsIn 2005, the BCSA became the first • Operate their businesses to the highest The Charter has been used to help Corus gives confidence to all of its Downstream benefits Corporate Responsibilityrepresentative organisation to launch a ethical standards in efficient and improve understanding of sustainability supply chains that its materials aresustainability charter. The objective of financially sustainable ways, in order to among steel construction companies, as Corus also takes responsibility for For Corus, corporate responsibility responsibly sourced, to provide a routethis charter is: undertake contracts that satisfy clients well as providing them with a tool to help managing the environmental impacts involves the integration of financial and for customers to obtain credits under the and add value for stakeholders them manage their businesses in more of its products once they leave its strategic goals with a commitment to the BREEAM family of certification schemes. sustainable ways. Charter Members also manufacturing facilities. Downstream, health, safety and well-being of its“To develop steel as a • Work to assess and minimise the effect agree to provide data which is used to Upstream influence the properties of its products and the employees and communities; a focus on information Corus provides to customers improving environmental performancesustainable form of of manufacturing and construction calculate sustainability Key Performance Corus is committed to minimising the can have a significant impact on the and providing sustainable products, and activities on the eco-efficiency of steel Indicators and benchmark theirconstruction in terms of construction through its life cycle performance. environmental impact of its upstream environmental performance of completed conducting all aspects of its businesseconomic viability, social operations. As a large customer, Corus is buildings and structures throughout with honesty and integrity. To read the • Work towards increasing the efficiency committed to wielding its influence over their life. Corporate Responsibility Report, pleaseprogress and environmental Sector commitments its global suppliers, encouraging them to visit of use of resources and energy in steel A second objective of the Charter takes adopt responsible practices. To support Meeting sustainable responsibilityresponsibility.” construction by promoting the the BCSA’s sustainability initiative these efforts, Corus has an online recovery, reuse and recycling of steel beyond individual companies and supplier assessment tool which it uses to procurement expectationsMember commitments • Foster the health and safety of requires the sector to engage directly screen potential suppliers, as well as to Corus has worked with the Building with building specifiers and bridge promote and monitor the performance of Research Establishment (BRE), theBCSA Member and Associate Member employees and others in the steel procurement agencies. The aim is to existing suppliers. Eden Project and other organisationscompanies that agree to be bound by construction industry, and operate develop suitable “green” specifications to develop its understanding of thethe charter have to make a formal generally in a healthy, safe and for steel construction that draw on the construction industry’s requirementsdeclaration of their commitment to environmentally sound manner established capabilities of BCSA Charter in relation to sustainable procurement.a set of sustainable principles, and Members in the supply chain. It supports the principles of BES 6001to be assessed and monitored against • Demonstrate social responsibility by and is working to assess its productsa range of environmental, social and promoting values and initiatives that to the requirements of this standard.economic criteria. show respect for people and communities associated with steelCharter Members formally declare that construction and with otherthey will adhere to the following aims organisations in the supply chain.and objectives:08 09
  • 6. The Kids of Steel programme, wherethousands of children across the countryparticipate in a mini triathlon, is one ofthe many community projects that Corushave initiated Delivering the triple bottom line Sustainable construction is about more than delivering environmental benefits – it’s Castleford Footbridge plays a key role in a about reducing social and local social regeneration project economic impacts too The triple bottom line Economic benefits of steel • Steel also retains its value. Because • Steel construction enables structures it maintains all of its properties and to be demounted and rebuilt without There are three elements to Steel construction has numerous qualities for life, it is endlessly noisy and dusty demolition. That’s sustainability: environmental, social economic benefits: recyclable. At the end of a building’s beneficial to the local community and and economic – known as the ‘triple life, the most economic solution for leaves behind no environmental legacy bottom line’. The environmental element • Steel has a high strength-to-weight a steel-framed building is either to understandably receives the most ratio, so less of it is needed to make refurbish it or for its components to • The steel industry requires skilled, attention, but to be truly sustainable a a quality structure, and smaller be demounted and rebuilt elsewhere. settled workers. There is little need structure must also deliver economic foundations are required. This means or desire for an itinerant workforce, and social benefits. that material costs for a given building Social benefits of steel and as such it provides more stable will be lower with steel than with any employment than in some other alternative Underpinning every environmental other sectors benefit of steel is a social benefit, as the • Steel construction is quick. Quicker examples below demonstrate: • The high strength of steel enables it construction means lower labour costs to achieve long spans, creating bright, and fewer time-consuming • Steel facilitates rapid construction, airy buildings that are a pleasure to preliminaries. It also means that a resulting in less disruption to the live and work in. Steel structures don’t Material costs for a building is finished earlier, speeding up local community around the building given building will be lower degrade with age either, so they never the development process and enabling site. There are fewer vehicle look tired and outdated. building owners to achieve a faster movements to site, very little on-site with steel than with any return on their investment. That’s vital noise and zero waste other alternative in challenging economic times10 11
  • 7. The stunning Cabot Circus roof, Bristol (photograph: MD & Associates) Design Best practice design guidance for steel construction is widely Target Zero available, supported by The steel construction sector is providing practical guidance online tools and resources for the construction sector guidance to underline its full commitment to supporting the Government’s drive towards zero carbon buildings The steel construction sector is Steel Essentials Tackling greenhouse Target Zero guidance committed to developing and gas emissions The Steel Essentials guide provides The steel construction sector is fully disseminating best-practice design helpful advice and useful reference The provisions of the 2007 Climate committed to supporting the guidance. A range of guidelines on across a number of steel construction Change Bill have committed the UK Government’s drive towards zero carbon implementing codes and standards has topics, including sustainability, health Government to a reduction in national buildings. It recognises that reliable data been published. This has been further and safety, fire protection, acoustic carbon emissions by 80 per cent is needed to help inform vital technical enhanced by extensions to the rules performance, structural design and compared to 1990 levels. Because decisions about building construction if which enable more innovative designs corrosion protection. A copy of this buildings in operation account for almost the Government’s zero carbon objective to be achieved. pocket guide can be ordered or half of all greenhouse gas emissions in is to be achieved. downloaded from the UK, the construction sector has a Steel construction guides That’s why the BCSA and Corus have major role to play in helping to achieve The Steel Construction Institute (SCI) is this target. resolved to provide and disseminate this the leading provider of guidance on the Leading the transition much-needed information. They have use of steel in construction. It publishes Achieving such a drastic cut in commissioned AECOM to lead a £1m, around 15 new reports each year. Recent to Eurocodes three-year development project to greenhouse gas emissions from guides have covered: The steel construction sector is taking construction will require radical changes generate fully detailed and costed a leading role in the transition to to the way buildings are constructed solutions for five building types that meet • Modular buildings Eurocodes 3 and 4 in the UK. It has and used in this country. Recognising the emissions reduction targets set out • Floor vibrations developed a number of tools, including this fact, the Government has set by Government. Guidance for each of the • Acoustic performance and detailing publications, courses and online demanding targets for the industry. building types will be published over a • Thermal bridging information, giving architects and All new residential buildings must be 15-month period, starting in November • Energy efficient housing using light designers step-by-step guidance on zero carbon in operation by 2016 and 2009 with guidance for school buildings. We recognise that reliable steel framing. how to use the Eurocodes. all non-domestic buildings must meet To find out more please visit data is needed to help inform this requirement by 2019. The SCI has also created the As part of its commitment to supporting vital technical decisions about website to give the new standards and in conjunction building construction if the those involved in steel construction with its partners in Europe, SCI has direct online access to up-to-date, developed a fast, free and easy route to Government’s zero-carbon high-quality technical information on the application of the Eurocodes objective is to be achieved. steel construction. through the multi-lingual website.12 13
  • 8. Mitigating Steelmakers and steelwork contractors climate are successfully working together to cut the carbon dioxide emissions associated with change steelmaking and steel construction Lakeside Energy from Waste Plant, Colnbrook Today, carbon dioxide (CO2) emissions Corus is now highly proficient at Corus has made a commitment to ULCOS – consortium for emissions reduction from steelmaking are around 50 per cent recovering the gases arising from its ensure that all its calculation lower per tonne of steel than they were blast furnaces, coke ovens and steel methods and data are consistent 40 years ago. Nevertheless, the steel plants. The gases are reused for process with the standards set by the World The ULCOS (ultra-low CO2 • A new generation of blast furnaces construction sector recognises that it has heating and electricity generation. Steel Association and other steelmaking) project is a consortium that recycle top gas and capture a significant contribution to make in On-site generation now accounts for authoritative bodies. of 48 European companies and CO2 for storage further reducing global CO2 emissions. 40 per cent of all electricity used by organisations from 15 countries, • Direct reduction of iron Corus – equivalent to a 700,000 tonne supported by the European • Smelting reduction Developing environmental Commission. It has an ultimate target • Carbon-reducing fuel technologies, Carbon reduction cut in CO2 emissions from conventional best practice electricity generation. of a 50 per cent reduction in such as electrolysis, hydrogen cells achievements Manufacturers of finished steel products emissions per tonne of steel by 2050. and biomass. Corus has long been working to improve are also taking positive steps to reduce Embodied energy advice Corus is a major partner in ULCOS. The level of investment in this projectXstrata Aerial Walkway, Kew Gardens the efficiency of its processes, to save their environmental impacts. The BCSA energy and reduce its environmental The steel sector is committed to has developed a carbon footprinting tool The first phase involves research to (around €360M) is testament to the(photograph: Jane Wernick, Jane WernickAssociates) impact. The company recently improving the design advice available on for its Members, which all of its ‘Gold’ evaluate a new generation of commitment of the European steel established a Climate Change Taskforce the embodied energy of buildings and status Charter Members are required to steelmaking technologies, while the industry to change things for the to develop and implement its carbon- other structures. The updated advice will use. The data from this tool provides Key second phase will operate the most better and to develop innovative reduction strategy, with a target of provide information on the embodied Performance Indicators for each member promising of these on a technologies that not only benefit us reducing CO2 emissions by at least 20 energy and carbon in a range of building and is used by the BCSA to develop demonstration plant scale. It will today, but also generations to come. per cent per tonne of steel by 2020, types with different framing solutions. It best practice guidelines. focus on four areas: compared to 1990 levels. will help the industry to move away from a simplistic ‘per tonne’ calculation towards more accurate and complete ways of calculating embodied energyOn-site generation now and carbon.accounts for 40 per cent ofall electricity used by Corus– equivalent to a 700,000tonne cut in CO2 emissionsfrom conventionalelectricity generation14 15
  • 9. Interior of Bridge Academy, Hackney,showing exposed composite flooring Thermal mass and CO2: facts Bridge Academy, Hackney, made excellent and figures use of exposed thermal mass (main photograph: Martine Hamilton Knight) The CO2 content of Carbon and energy impacts of Cradle to gate values The thermal mass myth Steel delivers optimum floor thickness structural steel steel products: There are other values in circulation for In modern buildings, the greatest Research shows that the optimum the carbon content of steel. Some are accessible mass is found in the concrete To calculate the environmental impacts of floor thickness required to achieve an Plate Sections Tubes HDG Purlins higher and some are lower than the floor slab. Independent research has steel manufacturing, the World Steel & rails effective thermal mass is readily values in the table opposite. Most other shown that the optimum thickness of Association adopts the ‘system expansion’ delivered by steel-framed buildings CO2 values have been derived by less concrete floor slab for providing thermal method of lifecycle assessment, which is (tonnes per 0.919 0.762 0.857 1.35 1.1 tonne of steel) rigorous methods than system mass is 75-100mm. This thickness of the preferred approach of the ISO 14040 There is a common misconception that Energy expansion. These other methods concrete floor slab is routinely available series of environmental standards. This 17.37 13.12 15.42 21.63 19.38 buildings must be heavyweight to (GJ per tonne generally rely on a cradle to gate analysis in almost all steel-framed buildings, approach considers all new steel to be part of steel) achieve an optimum thermal mass.Carbon dioxide of single global system of supply and and thus ignore the environmentally This myth has probably arisen because which are generally the lightest weight beneficial effect of recycling, which only form of construction.emissions associated demand. Credits are given for co-products It is standard practice to express these becomes apparent during the full cradle buildings such as churches are cool in used in the manufacturing process which the summer. However, the main reasonwith steel manufacture save energy or emissions, such as process figures on a per tonne basis. This may give to grave life cycle. Inferior cradle to gate that churches stay cool is because they Extra weight unnecessary the impression that steel has higher methods are used for comparison The extra weight associated with heavy,are kept low by effective gases being used to generate electricity. impacts than other construction products. because other material industries cannot have very few windows, which reduces bulky concrete frames is not required to solar gain.emissions reduction However, steel has a higher strength-to- provide robust cradle to grave data to improve thermal mass and is surplus to An example of the calculation method for weight ratio than most other structural the level of the steel industry. requirements. In fact, the extra mass ofinitiatives and extensive the carbon dioxide emissions associated materials meaning that one tonne of steel heavyweight concrete components mayuse of steel scrap with steel production can be viewed at goes a lot further. As a result, the CO2 actually increase the energy required to emissions associated with any steel heat and cool the building. sustainability building will be lower.16 17
  • 10. The Slimdek flooring system is a result of extensive research and development work Innovation A ceaseless quest for improved performance, efficiency and sustainability drives continuous in steel The structural A-frame uniting 201, Bishopsgate and the Broadgate innovation in structural steel Tower, London products and processes Innovation is essential if the construction Recent research and development • Photovoltaic metal roof and wall dimensional model of the steel frame can structural elements such as purlins sector is to meet the UK Government’s projects in structural steel include: cladding – Corus is collaborating with be built in virtual reality, thus facilitating and rails, floor decking, supports for sustainable development agenda. Australian company Dyesol – a world detailed planning of the erection infill walls and demountable partitions The steel sector has long embraced • Improving the efficiency of composite leader in dye-sensitised systems – to procedure; steel is prefabricated offsite, and as framing for residential and innovation, in both product floor decks develop a metal roof and wall cladding which increases accuracy and reduces modular construction. development and process efficiency, • Developing improved standard product with dye-sensitised solar cell liability to errors that would generate site to help reduce the carbon footprint of connections (DSC) functionality. DSC is an hazards. All of these things improve These developments have increased steel construction. • Improving the thermal performance of emerging photovoltaic technology that health and safety: the number one the use of factory-made precision building cladding to enable steel- mimics photosynthesis in plants. priority, and a vital socially sustainable components in building construction, Dedicated research and framed industrial buildings to meet the factor. Offsite innovation also has a reducing the need for site-based development new performance criteria for Part L of Innovation and the triple positive economic impact, reducing time adjustment and finishing trades. the Building Regulations required on site, as well as the need for Thorough, long-term and rigorous • Supporting the development of bottom line expensive site preliminaries. research and development is at the heart improved fire engineering techniques While innovation generates an of innovation in the steel construction leading to lower cost fire solutions improvement in environmental sector. Dedicated teams at Corus are • Developing improved methods for performance, it also has a positive effect Offsite innovations continuously seeking to improve the corrosion protection on the economic and social factors of the Offsite product innovations in the steel environmental and structural • Developing newer and quicker triple bottom line. For instance, steelwork construction sector include significant performance of steel products and the methods of core construction is increasingly pre-engineered in a way developments in the use of light-gauge efficiency of manufacturing, construction that makes pre-planning of operations steel in buildings. Cold-rolled sections and finishing processes. easier and more certain; a three have now been widely adopted for18 19