The Snug Guide to MMC


To help our clients embrace MMC we have produced The Brief Guide to MMC.

The world of Modern Methods of Construction (MMC) is expanding fast. As MMC suppliers increasingly vie for the attention of decision makers it can be increasingly difficult for clients and their architects to select the right approach for each project. There is no ‘one size fits all’ when it comes to MMC. How then are we to be confident we have made the right choices.

At Snug we believe in the KISS principle, Keep it Simple Stupid! Not easy in the increasingly diversified world of MMC. What is clear is that the simple answer; revert to traditional construction, is no longer an option. We have, therefore, set out to create a user friendly guide to MMC. This decision tree is intended to simplify the process of navigating through a modern project. It will help our own team, other architects, consultants and most of all our clients make the right choices when it comes to MMC.

First a bit of background. Construction has been trying to break out of the dark ages since Adam Smith identified that there were gains to be made in the division of labour and Henry Ford invented the production line. Despite many false starts in offsite manufacturing, progress is being made and it really does now feel like the construction industry is finally on the brink of an MMC revolution. If I was a stockbroker, and I’m not, I would be saying now is the time to invest in this emerging market. Local authorities in particular are getting behind MMC and increasingly requiring it in their projects.

So, what is MMC? In simple terms you could think of it as everything that isn’t wet construction. That could be everything that goes into making a building that is made in the dry, in other words off-site in a factory. On that basis you could say we have been doing MMC since the first bricks were brought in on trains from the clay pits of Essex to build Victorian London. It is however a little more complicated than that. At its heart is the concept of pre-manufacturing[1]; the more of your building that is made using factory methods of production the more invested you are in delivering an MMC building. Officially, according to the government definition, MMC is defined according to seven different types of manufacturing, depending on the extent of pre-manufacturing.

[1] The term 'pre-manufacturing' encompasses processes executed away from final workface, including in remote factories, near site or on-site 'pop up' factories. The pass test is the application of a manufactured led fabrication or consolidation process in controlled conditions prior to final assembly / install.

The diagram below illustrates all seven approaches to MMC.

The challenge is to make the decision on the most appropriate type(s) of MMC for different sites/projects and, as importantly when or where MMC is not suitable. Underpinning these crucial judgements is the challenge of how early these decisions need to be taken. The earlier the better with MMC.

The use of MMC is in many ways a decision of principle. Once you decide to do it the whole process from then on will be defined by it. This is one of the biggest reasons the industry is slow to adopt MMC. It changes established understandings of procurement and requires a courageous client who will work with their designers, warranty providers, insurers and funders to see MMC through, and that is not to mention their usual contractors who are unlikely to have more than limited experience with or access to many MMC systems. This means that traditional forms of procurement, including old school Design and Build, and traditional forms of construction, mostly masonry, are hard to kick. Current procurement rules largely hamper innovation by precluding less well established technologies and suppliers, who cannot complete or score sufficiently highly on standardised Pre-Qualification Questionnaire’s (QQ’s). This can lead unintentionally to:

  • Excluding newer and smaller organisations (SMEs)
  • Excluding novel delivery models
  • Excluding novel products
  • Stifling innovation

The procurement of housing delivery in particular is a complex and challenging area for clients. To enable innovation in housebuilding, robust and practical procurement solution, that are effective in delivering multiple-bottom-line value (social, environmental and economic impact), need to be developed and embedded in approaches to procurement.

Our Brief Guide to MMC is intended to help clients think through the early ‘big picture’ decisions. This needs to be one of the first conversations on the project because the ability to implement MMC and the likelihood of it actually happening diminish quickly as the project progresses and the powerful entropy towards traditional ways of doing things pulls the project back to safe and familiar territory.

To help our industry make better choices when it comes to MMC we have produced a simple decision-making process. These simple steps will guide you through the key issues and help ensure you adopt the most appropriate approach to MMC, avoiding delays, abortive work and unnecessary risk.

Step 1 – Which path will you take, MMC or Traditional?

The first question is, are you open to using MMC? Are you able and willing to trying something new, comfortable with the risks and able to invest the additional time for research in the early stages of the project? Are your funders comfortable with the technology and will your building users accept it? The status quo will always be tempting, appearing to be quicker, simpler and safer. Choosing MMC is in many ways a decision of principle, a choice to do the right thing and become part of a positive change in the industry. It might also be because innovation, sustainability, quality control, speed or cost certainty are key drivers. If your decision in principle is yes to MMC proceed to the next step….

Step 2 – How much of the building is to be in MMC? The choice is all of it (excluding the ground works) or only parts, including aspects of the Frame, Skin and Fitout ? This will primarily depend on how accessible your site is, in other words how big a piece of building can you reasonably transport to and lift onto your site, how repetitive your design can be, how early you are prepared to place advanced orders with manufacturers and whether reducing time and labour on site is valuable to you. To make the right choice you will need the right engineer and an architect who is openminded, able to efficiently evaluate a host of options at a conceptual level. Once you know the answer to these questions you can proceed to the next step…

Step 3 – Which approach will you take to pre-manufacturing? There are seven different types of pre-manufacturing. These range from fully structural 3D elements where the whole building is made off-site in the fewest possible number of pieces that will reasonably fit on the back of a lorry, through 2D structural systems such as SIPS, CLT and pre-cast elements to site installed labour reducing components such as brick slips and finally on to site processes that involve factory production techniques and even robotics

The diagram above illustrates just how complex and diverse MMC has become. This can make it complex and confusing to both define and navigate. We therefore propose that in the interests of simplicity and on the basis that level 7 is rarely applied in the UK the classification of MMC is reduced to three broader categories.

These are Volumetric, involving whole pieces of your building, Panel, involving fully formed elements of the structure, including walls, floors and roofs, and Component, which are medium sized bits of the building fabric and fitout such as non structural windows, stairs or joinery items?

At this step you will either be committing to a single modular supplier or begin the process of selecting a range of integrated and compatible systems. It may well be that access to your site is good, your design repetitive and you will be going wholly volumetric, working entirely with a single modular construction supplier who will effectively take on the project from here. You may even be selecting one of their ‘off the shelf’ buildings. This is what many people think MMC is. In most cases however, it is much more subtle.

The alternative to modular construction is to identify a whole range of compatible MMC systems that are appropriate to your building. These will be a selection of all three approaches, including volumetric pods, pre-cast wall and floor panels/cassettes, and a host of building components, some of which have been made in the factory for years, such as windows whilst others are more recent innovations, like brick slips and will need on site installation.

It is important to remember that the goal of MMC is to maximise both efficiency and quality by minimising how much of your building is made on site. It is all about pre-manufacturing, using modern methods of production to minimise on site construction. In many ways MMP might have been a more appropriate anacronym. Doing this effectively requires a design team to identify, evaluate and coordinate a wide range of alternatives. You will need to navigate contractors existing allegiances to a single supplier and will almost certainly need to bring in your contractor and/or primary suppliers early if you are to avoid the risk of abortive design work and cost uncertainty..

The choices made at this step will be critical to determining key dimensions for your layouts and will hugely influence your approach to procurement. Any future departure or changes to the choices you make here will have significant cost implications and a risk of abortive work. You will want to manage supply chain risks by establishing whether there are multiple suppliers for the particular systems you are looking at and whether your design is robust and flexible enough to cope with management contractor substitutions. These late changes can result in significant abortive design work and time spent redrawing and coordinating, often for little net gain. This leads us to our fourth step.

Step 4 – Identify the right suppliers – With MMC you need to know who you are going to work with early. This is a challenge for traditional competitive procurement. You and your design team will need the supplier’s help in order to effectively develop the design. Specifically, you need to understand their technical parameters as well as their price information. The challenge is they may not be willing to give this information away for free without an inappropriate level of commitment. At so early a stage in the design process this would be unwise. In the absence of appropriately experienced quantity surveyors who can price MMC with confidence, this will increasingly favour two stage tendering, allowing clients to court a number of potential suppliers in parallel. The biggest risk of MMC is committing to a single supplier too early. This reduces price competition and narrows both design and procurement options, with all the associated increase in risk.

It is therefore critical that clients choose a design team that can properly evaluate alternatives with an open mind at RIBA Stages 2 and 3. The right solution needs to be established through a fair and transparent procurement process where suppliers time and expertise is appropriately valued and, if necessary, remunerated as a design development cost.

It is critical that in the rush to pin down your approach to MMC you don’t throw the baby out with the bathwater by committing yourself to a single approach too soon, before the design, cost and procurement implications are properly understood. Even the most experienced of design teams can’t foresee all the consequences of such significant decisions.

Step 5 – Define your approach to procurement. – It is essential to establish the most appropriate approach to procuring your building. This cannot be based on any single imperative and a more complex matrix must be created and evaluated by the whole design team, and not just the project manager or cost consultant who will be unable to singlehandedly hold all the issues in balance.

It is important to recognise that MMC requires an equal level of commitment to modern methods of procurement. Off-site modular construction is not a panacea. Traditional procurement creates great design certainty but comes at too high a price and takes too long for most. Both Management Contracting and Design and Build manage cost certainty, time and risk on the client’s behalf whilst keeping supply chain competition. It is important to recognise the risks inherent in moving to an industry where a handful of large offsite modular manufacturers supply off the shelf design solutions. This approach is not without its risks, born out only recently by the unexpected demise of CIMC Modular Building Systems. The decision to liquidate by their Chinese parent company left a host of clients with no access to liability. This has exposed the risks inherent in putting all your eggs in one basket. We therefore believe that for most clients on most buildings there is a better way.

It is likely that for most building types, on most sites and for most clients a hybrid approach to MMC is the better way forward. At Snug we specialise in Hybrid MMC. This is about applying a modern mindset to the very traditional business of creating beautiful buildings and places. Like a great chef, we take the best ingredients and combine them into a bespoke recipe, carefully tailored to our client’s tastes, values and priorities. There is no one size fits all in construction. The best solutions are derived from the careful and considered application of a range of systems within an integrated and coordinated solution. This will likely include a combination of volumetric, panelised and component based systems, most often managed and delivered through a single management contractor who underwrites the liabilities on the project. By avoiding a final commitment to any single product or supplier until the design has been developed and systems refined and tested the client is able to reduce supply chain risk and maintain price competition. What is different about a modern method of procuring buildings using MMC is the need to involve the supply chain early. Two stage tendering is not so much about the early engagement of the main or management contractor but the early engagement of the supply chain. It is their specialist knowledge of often highly innovative and engineered products that the client and their design team need. This is invaluable and well worth paying for. Clients and designers need to establish good working relationships with these specialists and in turn the suppliers need to dispatch their technical experts rather than their sales-people as members of the design team.

The key to MMC is an openness to change and the drive to pursue best value, efficiency and innovation at every stage in the process. MMC is about more than modern methods of building. It is as much about modern methods of design, procurement, finance and even ownership as it is about construction. In the end MMC is all about the modern way to create better buildings and prosper people, delivering positive social impact for the whole of society.