The British Constructional Steelwork Association (BCSA) is the national organisation for the steel construction industry. It has represented the UK and Irish steel sector of over a century. Its members look to the BCSA to pioneer new approaches and innovations that will increase the steel industry's productivity while reducing its carbon emissions.

Offsite steel modules (steel frameworks integrated with roofing, cladding, flooring, electrics and other building services) can be more efficiently shipped to site and plugged in to a build. But they are mainly produced for high value, bespoke projects in the residential sector. Not enough best practice exists across steel or construction contractors yet. This means the supply chain - and their clients - are not benefiting from the efficiencies that modular manufacturing techniques offer large-scale builds, such as offices, retail centres, warehouses or public sector buildings. Added to that, supply chain often doesn't consider offsite processes until well into the build, which ends up causing delays or higher costs. These contractors also don't have the experience to navigate through the logistical challenges that offsite manufacturing can bring, such as how to transport the modules to sites that might be in hard to reach or in restricted city centres.

By creating a best practice prototype for offsite steel modules, the BCSA will help the steel industry be more productive and better meet the manufacturing requirements for large scale commercial or public sector builds. The BCSA is also helping the industry reach its 2050 net zero commitments by promoting more sustainable offsite processes and more efficient use of transport and resources. Offsite manufacturing can also support safety on construction sites and onsite skills shortages. By testing the prototype on a programme of 43 hospitals, the BCSA will be able to demonstrate the benefits of integrated offsite steel modules to the industry, and make it easier for steelwork contractors and other traditionally-onsite trades (such as mechanical and electrical trades) to engage earlier in the design process and collaborate more easily.

The BCSA Technical & Process working group realised that there was an opportunity to improve the steel industry's knowledge and use of offsite integration between heavy steel frameworks and light gauge steel modules. The BCSA identified the need for better guidance and best practice - a blueprint - that could help contractors across the supply chain contribute to the steelwork design and therefore the offsite manufacturing processes used. This in turn could increase the productivity of the steel industry.

Prompted by this insight, the BCSA put forward a proposal forward to its members in 2018 to research, develop and publish a free prototype for the industry that could be used by engineers, main contractors, steelwork contractors, mechanical and electrical contractors, and others in the supply chain. The idea being that this prototype would provide them with the knowledge, confidence and incentives to design, manufacture and construct large-scale steel-framed buildings using integrated offsite steel modules. Over the last two years the BCSA has gathered insights from its members through its regional meetings and brought it together in an online blueprint for the industry.

Contractors in the supply chain are not always involved in decision-making from the start, meaning that the design might not best support offsite processes or these process could be introduced too late in the build and end up adding costs and time rather than saving it. BCSA wants to encourage very early stage engagement from all suppliers and contractors. So, rather than the design being driven from the top down by the main contractor, the BCSA prototype allows more horizontal engagement by all parties so they can contribute to the offsite modular steelwork in a way that makes the build more efficient, productive and sustainable.

BCSA has developed and published a free online guide that includes design prototypes that can be used by engineers, main contractors, steelwork contractors, mechanical and electrical contractors and others in the supply chain. It sets out the blueprint for them to design, manufacture and construct mainstream steel-framed buildings that include integrated offsite steel modules. The design advice describes the design of steel concrete composite cores, which in some circumstances offer benefits of speed, accuracy, strength and stiffness, compared to a concrete core. It also describes the design of single storey columns, with concrete encasement if desired, which are highly suited for offsite manufacturing using robotic fabrication techniques. Further sections describe dry floor plates, erected as individual panels, which have the significant advantage of removing a number of processes from site, including the casting of concrete. 

BCSA is working with government procurement and testing this blueprint on a construction programme of 43 hospitals. The learnings from this programme will allow the BCSA and its members to further develop the prototype, treating it as a living document that brings together continual learnings and best practice.

The British Constructional Steelwork Association (BCSA) is the lead on this project. driven by the Technical & Process working group. Nine of the largest steel manufacturers have contributed their insights and experience to the prototype including Severfield, William Hare and Billingtons. All members - contractors and supply chain - have been sharing their insights and experiences of using offsite modular steelwork through the BCSA's regional meetings.

• British Constructional Steelwork Association
• Severfield
• Steel Construction Institute
• WSP

The Transforming Construction Challenge supported this project with funding and links to resources across the industry.

The steel construction industry has the potential to be more efficient and productive through the adoption of integrated offsite steel modules on large scale builds like hospitals, offices and warehouses. BCSA has developed a blueprint that will drive greater engagement among the supply chain. It provides contractors and suppliers with guidance on how to integrate light gauge modules into steel frameworks and increase the use of offsite manufacturing processes. This will help meet government objectives to reduce onsite construction time, as well as increase construction productivity, reduce cost and emissions, improve safety on construction sites and address onsite skills shortages.

Contractors and manufacturers will have increased knowledge and confidence in using integrated offsite steel modules on mainstream builds. The prototypes will also make it easier for steelwork contractors and other traditionally onsite trades (such as mechanical and electrical trades) to engage earlier in the process and collaborate more easily. The reduction of onsite assembly will improve safety on construction sites and address onsite skills shortages.

The advice from BCSA lives as a free online guide that includes design prototypes that can be used by engineers, main contractors, steelwork contractors, mechanical and electrical contractors and others in the supply chain. It sets out the blueprint for them to design, manufacture and construct mainstream steel-framed buildings using integrated offsite steel modules. Included in the prototypes are, for example:

• design of steel concrete composite cores
• design of single storey columns, with concrete encasement
• dry floor plates, erected as individual panels

Steel is the original offsite framing material, with up to 90% of structural steelwork already manufactured offsite. Over 900,000 tonnes of structural steelwork are fabricated offsite annually using automated manufacturing. The use of steel composite cores could shorten a construction programme from approximately 18 months with a traditional core to 10 months, and at a reduced overall cost. BCSA is working with government and applying the prototype to a programme of 43 new hospitals. While the steel industry declined by 20% in 2020, it saw 80% growth in 2021 and the BCSA wants to support British and Irish steel manufacturers make the most of further opportunities in the market.

Collaboration
Led by a trade association, this project has seen contractors that would normally compete for work, come together to solve this challenge and create a blueprint for the whole industry. To date, 379 members have downloaded the Design Advice and 324 have downloaded Advice to Clients from SteelConstruction.info. NB: These figures don't include any downloads from SCI.

Emissions
The blueprint supports the BCSA's 2050 decarbonisation roadmap as increased use of offsite processes will reduce emissions through the more efficient use of materials, transport and energy.

Time
The use of steel composite cores could shorten a construction programme from approximately 18 months with a traditional core to 10 months, and at a reduced overall cost.

Uptake
BCSA is using the Offsite Modular Steelwork prototype with government on a programme of 43 hospitals.

Offsite Modular Steelwork, Design Advice
UK structural steelwork, 2050 decarbonisation roadmap