1.Health and safety

Health and safety is a key business driver in construction. Offsite fabrication of components and rapid on-site assembly by skilled personnel make steel an inherently safe construction material. Industry surveys consistently demonstrate that steel is the safest material choice. Here we highlight the fundamental H&S safety benefits of steel construction and demonstrate how the sector ensures that these benefits are delivered.

2.Erected by skilled specialists

Steelwork contractors are highly skilled specialists, trained in a single discipline. They must hold industry recognised qualifications in the design, fabrication and erection of steel-framed structures. That means the steel elements are quickly and accurately assembled on site following proven, reliable and safe techniques. What’s more, unlike concrete, steel frames are full strength as soon as they are completed, enabling stairs to be fitted and providing safe access to the structure for other trades straight away. Steel decking for composite slabs also provides a safe platform after installation, as well as protection to lower storeys.

A number of innovative approaches to safe erection are now in common use on site. These include:

Dedicated lifting points on members and lifting brackets

Support frames that allow mobile elevating working platforms (MEWPs) to be used on erected steelwork

Edge protection attached at ground level prior to erection

The widespread use of nets for following trades

Offsite cutting of composite floor decking.

3.Rapid, waste-free assembly

All steel structural elements can be very precisely fabricated to tight tolerances before delivery to site, facilitating rapid and waste-free assembly. From the very beginning, specialist designers work with the construction team to ensure that the steel frame design can be manufactured and erected safely. Erection procedures can be planned in detail using 3D models and, for the most complex structures, trial assemblies can be staged to ensure everyone understands the required procedure.

4.Offsite fabrication for precision parts

Fabrication of the individual steel elements takes place offsite under controlled, highly regulated and safe factory conditions where the use of leading edge fabrication systems delivers precision-engineered components. With so much work carried out offsite, the on site construction programme is reduced and the build programme is relatively unaffected by adverse weather conditions. Furthermore, steel components can be pre-assembled or fabricated into modules either offsite or at low level, which reduces the need for working at height. Steel can be delivered to site as and when it is required, reducing the need for potentially hazardous on site storage.

5.Sector H&S assurance

The steel construction sector has put in place a number of measures to ensure its continued excellent H&S track record. These include:

To help small to medium sized steelwork contractors, a health and safety advisory service called Safety in Steel Construction (SiSC) has been launched, giving BCSA members access to direct and regular monitoring and advice.

The BCSA has introduced the Safe Site Handover Certificate (SSHC) which is supported by the HSE. The SSHC has improved communication between all parties involved and acts as a monitoring aid during the programme of works, covering site conditions and steel erection, ensuring that site risks are minimised.

The Steel Construction Certification Scheme (SCCS) is UKAS accredited, offering management systems certification services specifically tailored for the steel industry. A wide range of audits are carried out on quality, environmental, safety management and factory production control systems.

6.Vibration performance

For most normal office buildings, straightforward steel construction systems will meet the required vibration performance criteria without modification. For more vibration sensitive applications, such as hospital operating theatre floors, steel’s advantages can be captured with additional stiffening applied to the steel frame if required to meet acceptability criteria. Even with these additions, steel remains the most cost-effective and lightweight solution. Advanced analysis approaches are available to account for specific structural layouts, architectural arrangements such as corridor arrangements, degree of fit-out and location of partitions. These approaches have been successfully calibrated against on-site tests.

Long-span applications, for which steel is the only option, have been found to offer excellent vibration damping, despite common preconceptions (see SCI P354). The greater mass of the long span sections which participate in any motion reduces the magnitude of the vibration response. The steel sector has extensive experience in designing steel structures to ensure compliance with even the strictest vibration performance criteria. The National Health Service (NHS) in the UK demands some of the world’s most exacting vibration standards for its operating theatre floors. Detailed studies have shown that steel-framed buildings provide floors with vibration performance that meets or exceeds these stringent specifications, while still achieving the cost and flexibility criteria essential for the UK’s healthcare investment programmes.

7.Acoustic performance

Steel-framed buildings can comfortably satisfy the acoustic performance requirements for residential buildings, as set out in Approved Document E[1]. As with any framing material, including concrete, careful detailing is needed for floor finishes, walls, service penetrations and flanking. Robust Details are available for these elements, providing proven and reliable acoustic performance. Details are available for:Light steel framing systems,Composite floors

Acoustic details in SCI guidance (e.g. P372) are available for:

Light steel framing systems, including infill walls

Composite floors

Steel columns in blockwork walls

For external walls, where both acoustic and thermal insulation must be provided, infill steel-framed construction is the perfect solution. Insulation is provided within the frame, giving excellent thermal properties. In addition, infill solutions provide a robust wall with no gaps between the wall and main structure, which can be a problem with blockwork walls.

8.Sustainability

Steel is the leading construction material for sustainability, offering exceptional environmental, social and economic benefits. The balance between the three elements sees steel deliver a sound sustainability case and contribute to the circular economy.

Environmental benefits

Steel can be multicycled endlessly with no detrimental effect on its properties. When a steel-framed building is demolished, its components can be reused or returned to the steelmaking process to create brand new components. In the UK, 96% of steel construction components are recovered in this way. Globally, recycled steel accounts for 50% of new steel production.

Composite steel floors are given the highest (A+) environmental rating in the BRE’s Green Guide to Specification.

Because steel structures are significantly lighter than concrete equivalents, they require less extensive foundations, which reduces the environmental impact of the build. If steel pile foundations are used, these can be extracted and recycled or reused at the end of a building’s life, leaving no waste material on site.

Long-span steel solutions provide flexible clear span spaces that future-proof a building, offering an increased lifetime. Steel structures are durable and can be readily adapted, improving their economic viability as they can easily be updated or modernised.

The steel sector has developed a Sustainability Charter for steelwork contractors. Companies demonstrate their commitment to wide-ranging sustainable practices, and submit to an annual independent review of their commitment to the charter. A growing number of steelwork contractors are assessing (and reducing) their carbon footprint. The sector has developed a tool to assess the carbon emissions of steelwork contractors in a standardised manner and recent studies have enabled an average carbon footprint for steel fabrication to be derived.

A carbon footprint tool for buildings is available.

Many parts of the supply chain, including raw material suppliers, steel manufacturers, steelwork contractors and surface coating manufacturers have ISO 14001 environmental management systems accreditation. Also, increasingly, steelwork contractors are getting accreditation to BES 6001, the BRE's framework standard for responsible sourcing of construction products

Social benefits

Factory based steelmaking and fabrication supports a stable local workforce, benefiting family life and building stable communities. Offsite fabrication of structural steelwork is one of the safest forms of construction, promoting risk free working practices and allowing investment in developing the skills of the workforce. The impact of steel-based construction on local communities is minimised by the relatively short building programme, minimal site deliveries and the dry, dust-free and comparatively quiet construction process.

Economic benefits

Fabrication in controlled factory conditions results in high quality, defect free components that produce very little waste during the construction process. Furthermore, steel structures are durable and require little maintenance, extracting maximum value from the resources invested in the structure and minimising its whole-life costs. Long span steel sections enable large open plan, column free spaces to be created inside buildings, providing flexible areas that can be set out in an endless variety of configurations. Such ‘future-proofing’ means that the building’s use can be changed and the layout adapted many times – extending the lifetime of the structure. Short construction periods leads to cost savings in site preliminaries, earlier return on investment and reduced interest charges. Time related savings can easily amount to 3-5% of the overall project value, reducing the client’s requirements for working capital and improving cash flow.

9.Fire performance

The response of steel structures to fire is well understood, and extensive best-practice guidance is available. The performance of steel components and steel structures in fire has been researched more extensively than any other building material. The steel sector has invested decades of research into understanding the behaviour of structural steel components in fire - giving designers the confidence to engineer buildings safely in steel.

Unrivalled understanding of steel in fire

Large-scale natural fire test on cellular beams

Extensive testing of individual elements of structural steelwork and complete steel structures has furnished the industry with an unrivalled understanding of the response of steel buildings to fire. This has enabled advanced design and analysis techniques to be developed that allow very precise specification of the fire protection requirements of steel-framed buildings, often resulting in significant reductions in the amount of fire protection required. By comparison, relatively little is known about the performance of concrete structures in fire.

Efficiently engineered for fire resistance

Simple and advanced methods are available for the analysis of composite steel deck floors in fire; these can lead to the elimination of fire protection on many secondary beams. Pre-engineered shallow floor systems can even be designed to achieve a 60-minute fire resistance without additional fire protection. 

Fire protection innovations

The UK has an effective fire protection industry. The presence of a large number of manufacturers and applicators ensures that the industry is innovative and efficient. Thin film intumescent coatings are now the most popular form of fire protection in the UK, and a successful offsite application sector using this material has been developed. Offsite application thin film intumescent coatings offers considerable benefits, including:

Reduced construction times

Improved site safety

Speedier access for follow-on trades on site

Improved quality control

Reduced weather sensitivity.

Most long span and cellular construction now use the offsite application process.

10.Quality

Steel offers consistently high quality standards, precision products and guaranteed strength and durability in the most challenging environments. If you’re looking for quality assurance, structural steelwork delivers complete certainty, every time. Steel is produced to the most exacting specifications under highly controlled conditions, eliminating the risks of on site variability. Rigorous quality assurance processes give full traceability at all stages in the supply chain, from steelmaking through fabrication to erection on site.

All structural steel used in the UK is CE Marked, giving assurance that the material is compliant with the Construction Products Regulation. To help customers choose the highest quality contractors, all BCSA Members are assessed each year and categorised according to their technical and financial capabilities. As of 1st July 2014, all BCSA Members must be CE Marked.

Precision-engineered products

The manufacturing process for steel components is driven by advanced 3D modelling and numerically controlled fabrication machinery, resulting in high accuracy offsite and delivering a precision-engineered product. Because of the accuracy of individual components, steelwork is erected to tight tolerances on site. For particularly demanding fabrications, trial assemblies can be arranged to ensure the on site erection runs smoothly. This approach was used for the construction of Heathrow’s Terminal 5.

Strong, ductile and durable

Unlike concrete, erected steelwork does not shrink or creep. Steel is also highly durable. Steel piles extracted from an area with a high water table have been found to be fit for reuse after more than 100 years in the ground. Steel is strong and ductile too, making it highly resistant to accidental damage. If any damage does occur, it can easily be repaired by cutting, welding or bolting to restore its full strength. Steelwork erection on site is not restricted by weather conditions, other than high winds, and can continue year round, with no need for special protection measures in winter.

11.Economics

Independent studies consistently show that steel is the most cost-effective framing solution for multi-storey construction in the UK market.

Take a load off your foundations

Cost savings in steel buildings start at the foundations, where the loads imposed by a steel frame are up to 50% less than those of a concrete alternative. That means foundations can be much smaller and therefore cost considerably less. Foundations are a major component of overall building costs, so lighter foundation loads can have a big impact on costs. By way of example, the total mass of materials used to construct One Kingdom Street in London was estimated to vary between 32.3mt (steel frame) and 55.4mt (concrete frame); a 72% difference.