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ForewordThe last wave of construction innovations embedded into the way we design were devised morethan a century ago: steel frames (1890s), ‘dry-lining’ (1910s) and curtain walling (1910s). Andtoday, although external walls may no longer be load bearing and might utilise cavity walls, theyare still predominately built using ‘wet trades’, with one brick placed on top of another on site.In recent years we have seen a number of initiatives nudging us towards the next majortransformation in how we construct buildings. Driven by bodies such as BuildOffsite, theseinitiatives look at how we can maximise offsite fabrication and onsite assembly, minimisingonsite construction. The tipping point, where we fundamentally change the culture aroundhow we design for construction, has still to be reached.Many observers of the built environment industry query why the construction industry is notmore like the aerospace or car industries. Why have we not embraced lean thinking, kaizen orsix sigma ways of driving radical changes in what we do? The reasons are, of course not simple.Planes and cars are assembled in giant factories with controlled environments. Buildings mustbe assembled where they rest. Splitting them down into smaller, modular components that canbe assembled onsite is limited by transportation restrictions and other constraints. And, ofcourse, every site can be different, particularly in our cities where most of our buildings reside.The briefs, demands and outcomes of our clients can differ from project to project. The historiccontext can create further constraints: those who control the interventions placed in theselocations rightly impose stringent rules on the buildings that can be placed there.However, in the same manner that historic context does not impede design creativity (the 2013RIBA Stirling Prize was won by Astley Castle in Warwickshire, which was of a refurbishment ofa Grade II* Listed Building. We should not be using the reasons set out above to impedeinnovation in the way we design for more effective construction outcomes. If there areconstruction methods that are faster, cheaper, safer and better for the environment we shouldbe embracing them.In reading the early drafts of this publication I realised that this publication was not aboutmodular units or flat pack construction, it was about how construction could be transformedwith Stage 5 of the RIBA Plan of Work considered as ‘Assembly’ rather than ‘Construction’.I counsel every RIBA member to read this document and consider how they can use themethods set out here to help transform the way we design to make it faster, cheaper, saferand more environmentally friendly to build.Jane DuncanRIBA President, 2015–20172RIBA Plan of Work: Designing for Manufacture and Assembly

PrefaceThe construction industry is reinventing itself, implementing significant changes in the way thatprojects are delivered. The government’s 2025 productivity challenges are a core driver ofchange. The industry has already made progress towards the adoption of Building InformationModelling (BIM) by harnessing new digital technologies. Collaborative joint venture approachesto project delivery are now commonplace as client, contractor (and their supply chain) anddesign team relationships are re-examined and improved in order to deliver innovation.Contractors are working with enlightened designers to innovate in many different ways.Skanska, Laing O’Rourke, Carillion and Costain are working to adopt lean thinking and offsitemanufacturing processes. At Skanska this is called ‘industrialisation’; Laing O’Rourke use theterm harnessed for this publication: ‘design for manufacture and assembly’ (DfMA): Carillionhave coined ‘offsite & MMC (modern methods of construction)’ and Costain use ‘factorythinking’. Through the Offsite Management School we have agreed a common language, skillset and approach, which include five key elements: standardised design, design formaintenance, logistics, offsite manufacture and onsite assembly. It is about having anindustrialisation mindset.The Offsite Management School is helping subcontractors and their supply chains to learnnew skills, but the School now needs the support and innovative thinking of designprofessions to drive further, more radical changes with even greater efficiencies.As well as delivering projects faster, lowering costs and improving quality, the use of DfMAtechniques will also result in better operational and in-use outcomes. There is no downside.By consistently embedding DfMA into your Concept Design at Stage 2, you will be able todrive the productivity gains necessary to deliver the UK Government’s Construction 2025strategy and be part of a new, safer, more sustainable construction industry.I hope this guide and the supporting FAQs, glossary and online resource library, provided bythe Offsite Management School, will help introduce you to DfMA thinking, enabling you toharness it at the earliest possible project stage.Rob FrancisChair, Offsite Management SchoolDirector, Industrialised Solutions, Skanska UKRIBA Plan of Work: Designing for Manufacture and Assembly3

IntroductionThe global construction industry is worth 5 trillion and demand is growing rapidly.Independent research by KPMG shows that construction productivity has been flat since1997, while in the UK generally, productivity has risen by 25% (figure 1).UK productivity (1997 100)1.31.21.11.00.90.81997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013ConstructionEconomyFigure 1: Productivity improvement over timeSource: Office for National StatisticsThe United Nations predicts there will be a 33% increase in the world population by 2050, andthat a similar proportion of the population will move to cities. This will drive demand forhousing, infrastructure and commercial property. However, the world is using up resources atan unsustainable rate. According to WWF, we would need three planets of resources ifeverybody were to live Western European lifestyles, and six planets if we all lived like NorthAmericans. Forty-five per cent of the world’s carbon emissionscome from buildings, 90% of the world’s hardwood goes to theconstruction sector and 50% of the world’s landfill waste comesfrom construction. The statistics are clear. Construction is a majorcontributor to the depletion of global resources and as such canplay a major role by devising solutions to minimise the use ofresources, although a step change is needed to deliver thebuildings we need in a more efficient and sustainable way.4RIBA Plan of Work: Designing for Manufacture and Assembly

IntroductionBuildings need to suit specific uses, users and locations. This has been a barrier toharnessing the benefits of offsite manufacture and mass production. Design for manufactureand assembly (DfMA) changes this. It enables the mass-customisation of solutions alreadyused by other industries to become commonplace in the built environment industry. Byharnessing new digital design processes and aligning them with offsite manufacturingfacilities, new and profoundly different design processes will be generated. This will enable thedesign team to contribute to the UK Government’s Construction 2025 strategy ambitions of50% faster delivery, 50% lower greenhouse gas emissions, 50% improvements in exports(reducing the trade gap) and 33% lower costs – all by 2025.This publication examines how the design team can contribute to the process driving radicalimprovements in productivity.Design formanufactureand assemblyLeadershipand cultureSupplychainmanagementChangemanagementDesign formaintenanceOffsitemanufactureMarketingand siteassemblyLogisticsFigure 2: A DfMA mindset: through the stages of construction industrialisationRIBA Plan of Work: Designing for Manufacture and Assembly5

What is design for manufactureand assembly?Design for manufacture and assembly(DfMA) is an approach that facilitatesLevels of offsite DfMAgreater offsite manufacturing, thereby Component manufactureminimising onsite construction. It allowsbuildings to be constructed morequickly and safely, and more Sub-assembly Non-volumetric preassemblyresource‑efficiently and cost-effectively. Volumetric preassemblyDfMA does not impede design thinking Modular buildingsor require any compromise in the qualityof finishes or materials.Designing for manufacture is the process of designing in a manner that enables specialistsubcontractors to manufacture significant elements of the design in a factory environment.Panelised cladding systems have been designed in this manner for many years. Designing forassembly considers how aspects of the design can be designed in a manner that minimisesworks on site and, in particular, in a way that avoids ‘construction’. For example, a handrailsystem can be designed so that half landing lengths can be quickly installed into socketspre-positioned in the stair structure, possibly incorporated into precast units.DfMA harnesses a wide spectrum of tools and technologies. The underlying goal is to usedesign processes that help facilitate a collaborative approach along the whole value chain,embracing design teams, clients, contractors and offsite manufacturers. DfMA encompassesmany techniques, including: Volumetric approaches, which create as much finished product as possible in the factory,minimising onsite labour completely. ‘Flat pack’ solutions, which output a kit of parts that can be quickly assembled on site. Prefabricated sub-assemblies (M&E services, for instance), which can be deployed inconjunction with more traditional elements, sometimes with similar effects to more‘complete’ prefabricated systems.In all these instances, assembly of elements may be undertaken remotely, or in a facility localto the site that has been established specifically for a project, perhaps to encourage andpromote the use of local labour resources.6RIBA Plan of Work: Designing for Manufacture and Assembly

What is design for manufacture and assembly?Adopting a DfMA approach does not mean that standard ormanufactured elements need to be adopted. It may simply meanharnessing design rationalisation, materials optimisation,just‑in‑time delivery or logistics planning in order to achieve highrates of productivity on site. Seeking to find the most efficient wayto deliver a project inevitably reduces the resources required(whether this is measured in carbon, cost or time) while increasingpositive aspects (health and safety, quality and certainty). DfMAcan be applied to one-off small-scale projects as well as tolarge-scale projects and frameworks.Case study: Leadenhall Building Architect:Rogers Stirk Harbour Partners Contractor:Laing O’Rourke80% of the Leadenhall Building wasconstructed offsite using LaingO’Rourke’s DfMA approach and offsitemanufacturing capabilities.The DfMA approach emphasised eliminatingwaste at source through efficientprocurement, design, manufacturing andengineering methodologies. This approachincreased the quality of materials andinstallation, reduced site waste, and reducedoverall deliveries to site by 50%, avoiding airpollution and congestion.RIBA Plan of Work: Designing for Manufacture and Assembly7

Why is DfMA an essentialcurrent topic for designers?Over recent years, DfMA hasbecome more widely adopted ina number of constructionsectors, including healthcare andhotels. Increasingly, clients,designers, contractors andoperators are becomingconvinced of the benefits ofDfMA and are keen to apply theapproach to more complex andbespoke buildings.Client perspective“As a client, we are trying to improvehow we serve customers, keep their billslow and keep our employees and supplychain safe. DfMA is an easy choice andwe expect our design community to‘hard‑wire’ offsite thinking and standardproducts into designs so we can realisethese benefits.”Kieran Brocklebank,To be successful, DfMA requiresHead of Innovation, United Utilitiesthe design team to thinkdifferently at Stage 2 ConceptDesign, in particular about thebuildability aspects of theirdesigns. DfMA might not impact on a building’s appearance, but if the design is to be suitablefor developing for modern methods of construction during Stage 3 Developed Design andStage 4 Technical Design, it is essential that DfMA is considered at Stage 2. DfMA is not justabout efficient construction processes. When it is properly implemented it improvesoutcomes for costs, the environment, health and safety and time (these points are coveredlater in this publication). Fundamentally, DfMA requires the design team to shift their thinkingaway from traditional means of construction, to scenarios where buildings are assembledrather than constructed.Building Information Modelling (BIM) is facilitating a culture of innovation and collaborationthat assists the adoption of DfMA. The efforts made to create highly detailed, data-rich,fabrication-quality models, which bring together many design disciplines and the design workof manufacturers and specialist subcontractors, will continue to deliver better outcomes yearon year. It is rapidly becoming the norm that a client expects to procure a project, design teamor contractor that uses innovative digital design-to-construction processes. The number of‘construction innovation’ questions in tender documents continues to increase along withtheir complexity. These allow innovators to continue to differentiate themselves from theircompetition, as BIM on its own becomes less of a differentiator.8RIBA Plan of Work: Designing for Manufacture and Assembly

Why is DfMA an essential current topic for designers?While the increasing body ofContractor perspectivepublished BIM case studiescontinues to demonstratereplaced architects or other“Construction industrialisation willallow the industry to tackle the skillsshortage by significantly improving theefficiency of those who currently work onsite, and through the increased use ofmodern, efficient factories we will attractand retain a more diverse range of talentinto the industry.”members of the design team, andRob Francisneither will BIM. Designers needDirector, Industrialised Solutions, Skanska UKsignificant improvements indesign-to-constructionprocesses, these successesalone will not meet the targets setout in Construction 2025. Otherinnovations are required. CAD(computer-aided design) has notto develop the collaborativebehaviours required to deliverbetter and greater innovation,particularly at the boundaries between design, manufacturing and assembly and constructionon site. Some clients, such as Highways England, are starting to require compliance with theBS 11000 collaborative working standard. This is ideally positioned to enable the benefitsoffered by BIM and DfMA to be realised.Simply, those who consider DfMA as part of their BIM processes, who examine innovativeways of using digital tools to transition more effectively from design to construction and whoadopt more collaborative ways of working, will secure more work.From the contractor’s perspective, a major benefit of DfMA isthat it allows the labour required on a project to be redefined.The Chartered Institute of Building’s Skills Report 2013indicates that there is a severe skills shortage in the UKconstruction industry: 82% of construction professionalssurveyed for the report believe a skill shortage currently exists.While not mentioned in the report (published in April 2013), theissue will be exacerbated by the emergence of other resourceintense major projects, including Thames Tideway, HS2, HS3,Crossrail, Crossrail 2, Hinkley Point C and Sizewell C, and by the fact that around 25% ofpeople employed in the construction sector are expected to retire in the next five years.By developing solutions that are ‘assembled’ rather than ‘constructed’, DfMA offers theprospect of using fewer people generally. Those who are required will have broader skill sets,providing a greater resource for the construction industry to draw from. DfMA also creates amore controlled and safer environment for those people to work in, away from traditionalconstruction sites. Combined with the increased productivity generated by manufacturing in afactory, this approach eases the pressure created by the skills shortage.RIBA Plan of Work: Designing for Manufacture and Assembly9

Why is DfMA an essential current topic for designers?Case study: Flying factories Main Contractor:Carillion Specialist Contractor:Skanska Rashleigh WeatherfoilFor Phase 1 of the Battersea Power Stationsite redevelopment, Skanska manufactured540 utility cupboards (as pictured) in a flyingfactory, and constructed another 300 on site(the onsite construction was driven by siteconstraints, but provided good data on thecomparison of the two techniques).Compared with onsite fabrication andtraditional methods of construction, thefollowing savings were made:Modern ‘flying factories’is a concept for offsitemanufacturing andindustrialisation ofconstruction projectsusing temporary andflexible factories, whileapplying lean principlesto the manufacturingprocess.10 44% reduction in cost. 73% reduction in quality/rework defects. 60% reduction in time.RIBA Plan of Work: Designing for Manufacture and Assembly

What are the benefits of DfMA?DfMA might not influence the appearance of a building, but,if DfMA issues are carefully considered during thedevelopment of the Concept Design at Stage 2, it cansignificantly improve the construction outcomes. The benefitsof DfMA include: 20%–60% reduction in construction programme time. Greater programme certainty. 20%–40% reduction in construction costs. 70% reduction in onsite labour, with subsequent improvements in health and safety. Reduced need for skilled labour on site. Better construction quality. Better environmental outcomes, including reduced waste. Fewer queries from site.DfMA eliminates or reduces some of the problems typically associated with traditionalconstruction. Advanced manufacturing firms routinely achieve productivity rates of 80%, but for onsiteconstruction workers, productivity can drop to as low as 20% (source: Totalflow Ltd).Furthermore, site-based labour can cost up to twice as much as factory-based personnel.Employing lower cost, more productive workers has a significant impact on cost outcomes. Poor productivity and manpower shortages account for up to 37% of delays on site (source:HM Government department capital programmes). An ‘offsite’ approach reduces the totalnumber of hours required on site, thereby reducing the risk of delays. Guidance on the NEC contracts estimates that in traditional ‘construction’, lack of designinformation accounts for 8% of delays on site. By manufacturing offsite, fewer decisions arerequired on site, substantially r

RIBA Plan of Work Designing for Manufacture and Assembly overlay This Overlay to the RIBA Plan of Work 2013 includes additional task bars to support Designing for Manufacture and Assembly. It should be used in conjunction with the RIBA Plan of Work 2013: www.ribaplanofwork.com Concept Design Developed Design Technical Design Handover