MMC Defined: Modernising The Construction Industry
Increasingly, factory manufactured buildings are seen as the ideal modern construction method. The Structural Timber Association (STA) is working hard to place timber at the forefront of this building revolution.
All factory operations in contemporary production environments are now controlled by quality management system such as ISO9001 or the STA’s membership and quality standards scheme – STA Assure. This ensures that the complete manufacturing process is in line with the customer’s expectation for consistent, high levels of quality.
Until recently, the housebuilding industry has been slow to utilise modern methods of construction even though offsite technology allow homes to be constructed up to 30% more quickly than traditional building methods. Not only do offsite methods require fewer people onsite, helping to mitigate the skills shortage, these methods are also
more efficient, reliable and sustainable.
With the Government’s presumption for the specification of offsite technology for all public sector projects together with funding support – there has been a call for definitions to be established. On behalf of the government, Mark Farmer (CEO of Cast Consultancy) has termed seven modern methods of construction definitions, one for each category of pre-manufacturing processes. The STA supports these definitions, which have been ‘futureproofed’ for key stakeholders and will be relevant for mortgage, insurance and
underwriting perspectives to collect data on building/system performance and risk.
OFFSITE/MMC DEFINITIONS Pre-manufacturing (3D primary structural systems): Structural chassis, which may be combined with internal fit-outs, external cladding, roofing and ‘podded’ room assemblies.
Pre-manufacturing (2D primary structural systems): basic framing for walls, floors, doors, stairs and roofs; enhanced consolidation of insulation and internal linings; further enhanced consolidation of insulation, linings, external cladding, roofing, doors and windows.
Pre-manufacturing components (nonsystemised primary structure): driven/screw piling, pre-fabricated pile caps/ring beams, columns/shear walls/beams, integrated columns, beams and floor slabs, staircases and preassembled roof structures (trusses/spandrels).
Additive manufacturing (structural and non-structural): substantive structural forms/components and non-structural components.
Pre-manufacturing (non-structural assemblies and sub-assemblies): volumetric podded assemblies for bathrooms, kitchens and unit M&E central equipment and panelised/linear assemblies for non-structural facades, roof assemblies/cassettes, unit M&E distribution assemblies, infrastructure M&E assemblies, floor cassettes,
partition cassettes and doorsets.
Traditional building product-led site labour reduction/productivity improvements: internal and external walling products, large format roofing finishes, pre-sized traditional materials and interfacing features.
Process-led site labour reduction/
productivity/assurance improvements: site encapsulation measures, standardised and sacrificial temporary works, BIM connected lean delivery framework use, site worker augmentation, site worker productivity planning tools, site process robotics and drones, autonomous plant, equipment and drones and digital site verification tools.
Quality Assurance and Warranty of Offsite/MMC Alongside clear offsite definitions, the government are developing a unified quality assurance scheme for assessing offsite technologies. The scheme will also act as a gateway to acceptance of the final homes for warranty, mortgage and building insurance offers.
To develop unified assurance, the government have formed a ten-point checklist:
• Needs to be clear on technical longevity assurance of the product, not just component plans
• Needs to identify the abnormal cost of insurance-led reinstatement, checking whether repairs are capable of ‘open sourcing’
• Needs to be associated with a ‘mainstream’ warranty
• Needs to recognise the importance of valuer advice
• Needs a single, unified, assurance platform in the UK
• Needs clearer definitions of MMC
• Needs to be holistic in warranty terms
• Needs product and process assurance to be better linked to people via skills and competency certification
• Needs a single open source repository of how housing stock is built
• Needs better education and awareness of latest technologies.
The government have also created an independently curated hub for offsite-related data collection to improve product knowledge, transparency and stakeholder education. They will build stakeholder confidence through robust and unified technical assurance processes for offsite and improve links to insurance and financial products. The aim is to enable demand-led change that underpins increased capacity to build homes in a more productive way to a higher quality. To encourage sector growth, the government will take the following actions to further develop offsite:
• Stimulate offsite growth through the Accelerated Construction Programme for offsite to encourage investors into the sector and enable current suppliers to expand
• Support a joint working group with lenders, valuers and the industry to ensure that mortgages are readily available across tested construction methods. This will include encouraging industry use to develop a stronger set of core data to measure the use and performance of different technologies
• Align the planning system with offsite developments
• Work with local areas to deliver growth, job opportunities and faster build times
• Consider opportunities with the Home Building Fund for offsite firms to access growth funding. The government recognise that offsite projects should use the same finance as traditionally constructed projects.