MICHAEL O’REILLY, Director, O’Connor Sutton Cronin, writes about how modern methods of construction, and in particular off-site manufacturing, is delivering solutions for Irish construction, but the sector needs to address several issues before it can fully benefit from the construction method.
The construction industry is constantly evolving, sometimes in reaction to impositions on the market, sometimes with a longer-term strategic view. But in the past year, the Covid-19 pandemic turned everything on its head, forcing us as an industry to review everything that we do, overhaul how sites operate and reassess the process by which we deliver our built environment.
One aspect that will change irrevocably for many consultants and contractors is the increased reliance on Modern Methods of Construction (MMC). But several elements need to put in place before we can say that we have a workable system that will get the full benefit that MMC has to offer.
Health and safety requirements, compliance with building standards, skills shortages, achieving high levels of thermal and acoustic performance, reducing waste and site vehicle movements, and achieving greater efficiencies and shorter build times are all factors that have been ushering in the use of MMC on projects over the past 20- plus years. And it now appears that MMC is set to play a more significant part in how we build somewhat earlier than might have been imagined hitherto.
Modern Methods of Construction
MMC is an umbrella term used to define numerous processes that encompass pre-engineered and prefabricated elements, which reduce the level of on-site labour required and also provide programme certainty.
Today, MMC covers many forms: Concrete insitu formwork systems; jumpform and slipform; precast cores and precast concrete solid panels; twin walls; and prefinished insulated precast external façade panels. There are also full external wall panel systems, internal-external-insulated panels with and without windows. Bathroom and kitchen pods offer significant time savings, assuming there was substantial repetition. Once heavyweight, newer versions are lightweight and come with or without floors. Timber frame also provides considerable time savings on residential housing development. Light metal frame systems offer a pre-engineered solution. Commercial developments are also opened up to steel frame, pressed metal flooring systems, and encased ASBs to reduce the applied fire rating requirements. Siphonic drainage systems reduce the number of downpipes and the extent of external civil drainage requirements. It should be noted that many of the fast-build Covid-19 medical facilities could not have been constructed without MMC.
The various types and categories of MMC are probably most easily understood from the pictogram below.
Pictogram displaying categories of MMC.
A brief history of MMC
At the height of the last boom, the scale and number of projects on site moved at an astonishing pace. At the height, the Irish construction sector outputted over 93,000 residential units in 2006. It was also a time when the construction sector used various forms of MMC to deliver projects quicker and more efficiently.
More recently, construction technology has been evolving at astonishing speed. The growth of Lean, building information modelling (BIM), and other digital construction techniques, as well as the requirement for more energy-efficient buildings, has meant that consultants and contractors are better placed to use off-site construction for sustainable and efficient solutions.
Covid-19 has highlighted the need for engineers and contractors to find new, safer and more efficient ways of delivering our built environment. But Covid-19 has also been instrumental in creating a sea-change in Irish construction. Looking to the immediate future, while consultants will be looking for more cost-effective and sustainable build solutions, contractors will be looking to reduce the number of personnel on their sites with the result that MMC will be an integral part of the Irish construction landscape going forward. Many specialist contractors and main contractors have responded by establishing off-site facilities to meet their and the broader market’s needs.
Innovation and Digital Adoption Sub-Group
At government level, in 2019, the Department of Public Expenditure and Reform (DPER) commissioned the KPMG/Future Analytics Report on “Productivity in the Irish Construction Industry”. This report identified seven priority actions as needing to be implemented in the context of delivering the next National Development Plan.
The Construction Sector Group (CSG), comprising Government and industry, set up the Innovation and Digital Adoption Sub-Group to implement these seven actions. MMC is one of the seven actions identified.
An MMC working group was set up to report back on the requirements for establishing a sustainable MMC market in Ireland.
The working group defines MMC as including modularisation, off-site fabrication, off-site design and manufacture, and a range of other technologies and methodologies. It sees the ultimate goal of MMC as cutting down on labour, reducing costs and build time, and ultimately delivering greater value for clients. Digital Adoption Sub-Group chairperson PJ Rudden is quoted as saying MMC is meant to deliver the most efficient construction methods using BIM to increase innovation and digital adoption with minimal wastage on circular economy principles. But despite its use in some sectors, the industry as a whole has been relatively slow to adopt MMC and other advanced methodologies.
If MMC is to transform Irish construction, several obstacles will have to be overcome first.
Productivity in Irish construction is still not high enough, and digital adoption is low. From a consultant’s point of view, there are challenges relating to involvement in the pre-planning process and certification of systems that need to be addressed.
Early integration of MMC specialists within the design team is critical to get the best outcome for the project. To date, MMC specialists have tended to be only brought on board on projects at tender stage. The reality is that the MMC specialists need to be on board at the earliest possible time. Bringing them in at the pre-planning stage means the consultant team has an MMC specialist to offer solutions that can be fed into their design decisions. At the moment, in most cases, plans are presented to the MMC specialist without them having had any input to the design, with the result that it is not always possible to make palatable changes.
Certification and split responsibility is the second most critical issue for consultants and assigned certifiers. Work is required by all in the industry to understand what and when is the split, who certifies, when is it inspected, what type of certification is required and who provides it.
These issues are not insurmountable, but more engagement between the construction industry and professional bodies will be required.
In closing, the ongoing integration of third-level universities, colleges, institutes and apprenticeship programmes, coupled with developments in BIM and digital construction technologies, are the foundation stones for the future development of MMC in Ireland. Between the work of the cross-sector Digital Adoption Sub-Group and the changes that have already taken place on sites across the country, it is up to the industry to make the changes that will make MMC work for everyone.
Michael O’Reilly is a director with O’Connor Sutton Cronin, with a focus on Structural and Civil Engineering design excellence. He is the incoming honorary secretary of the ACEI and sits on the ACEI Structures Committee.