David Atkinson at Metsec explores why harnessing digitalisation and lightweight steel framing can maximise the benefits of MMC as the industry pursues its various goals
The UK construction industry faces a challenge to improve the availability, quality and affordability of new homes. Modern Methods of Construction (MMC) encompasses a broad range of offsite and onsite techniques which have evolved to achieve these objectives.
Today, MMC needs to embrace demands for environmental responsibility, safety and information flow. Combining offsite manufacturing with digitalisation of construction promises can unleash the potential of MMC to deliver the key advantages of speed, efficiency, safety and sustainability.
Key to the process for specifiers is consistent, data-driven design. Three areas are becoming particularly important drivers for architects: the drive towards carbon net zero, fire performance, and the ‘golden thread’ of project data.
Achieving net zero in 2050, and an interim goal of cutting carbon by 68% before 2030, will rely on applying expertise in buildings’ design, and careful selection of the materials used in their construction. It is here that lightweight steel framing offers a number of advantages. While the process of making and converting steel into building components may appear carbon intensive, the advantages it offers can mitigate the building’s carbon footprint.
Steel framing systems offer the potential for zero material wastage as all components are designed and manufactured to exact dimensions and assembled to strict tolerances. Lightweight steel framing reduces the burden on foundations, it can be designed and constructed with less material, and using methods which have a reduced environmental impact.
Pre-panelised steel framing systems are precision-manufactured in controlled factory conditions. Each panel precisely matches the requirements of the project and is delivered to site ready for rapid installation without the need for potentially carbon-intensive wet trades. Also, steel has a re-use and recovery rate that makes it one of the most recyclable materials.
In the wake of the Grenfell Tower fire, specifiers and the entire construction industry have looked to manufacturers to provide evidence-based performance data to demonstrate the suitability of products and systems in providing resistance to the spread of fire.
Steel framing systems can offer the assurances required, with reputable manufacturers amassing large suites of test data as a result of continuous investment in independent fire testing by UKAS-accredited laboratories.
Pre-panelised steel framing systems can be tested using many different combinations of sheathing board, insulation and dry lining, to ensure that designers are given maximum choice in design and specification.
The ‘Golden Thread’
Here, again, the tragedy of Grenfell has acted as a catalyst for change, with Dame Judith Hackitt’s ‘Building a Safer Future’ report recommending a ‘golden thread’ of information to support CDM duty holders on projects.
Within its definition, the golden thread is seen as holding the information that those responsible for the building require to show that its design was compliant with applicable Building Regulations, and provide evidence of meeting the requirements of the new Building Control process throughout its design and construction or refurbishment. In addition, the information will help identify, understand, manage and mitigate building safety risks in order to prevent or reduce the severity of the consequences of fire spread or structural collapse throughout the life cycle of a building.
Amongst other requirements, the definition goes on to stipulate that information should be updated as and when necessary, be stored digitally, be accessible to relevant people and apply through design, construction, occupation, refurbishment and ongoing management of the building.
At the heart of the golden thread are 10 guiding principles covering, amongst other things, accuracy, trust, residents’ security and accessibility to, and longevity of, the information.
The processes necessary for the successful implementation of MMC are already based on advanced information systems, and lend themselves perfectly to the requirements and principles of the golden thread. In the case of lightweight steel framing, this thread of information starts with the architect’s initial designs and runs through the entire design, manufacture and installation process.
Advanced 3D design systems, managed by an experienced in-house engineering team, are used to create detailed models of structures incorporating the pre-panelised system. Frame manufacture and assembly details are produced from these precise designs together with installation schedules stipulating exactly which panels go where.
With the installation of steel framing systems normally undertaken by a single specialist installer, the number of stakeholders involved in a project is minimised, streamlining information flow and simplifying information management. Additionally, many MMC projects utilise BIM to co-ordinate the design, manufacture and installation information used through construction to handover to the building’s owner.
David Atkinson is specification manager for framing at Metsec