Laing O’Rourke

Transforming construction

It’s not just a cliché: time really is money. Increasingly, governments and developers want and need more for less – and as quickly as possible.

By Dr Phillip Cartwright
and Dr Gavin Davies


 

Faster, Better, For Less – How DfMA is transforming construction

A new retail development that falls behind schedule, for instance, or a delayed commercial venture awaiting the arrival of tenants, represents a huge commercial risk.

Beyond cost-savings, councils need schools to open in time for the new academic year in order to hit education targets; developers and architects expect their ideas to be flawlessly executed as their visions come to life; and any process that reduces the safety risks inherent in construction will be applauded.

Our response to these issues is Design for Manufacture and Assembly (DfMA), which is revolutionising how we evolve towns and cities within challenging restraints.

The approach is structured and simple, but the end product remains of high (if not better) quality, with tightly controlled factory processes ensuring accuracy and consistency.

DfMA produces precast and preassembled buildings and their component parts – from columns, beams and walls to sleepers, cladding and building systems – to a cost, time and specification with which traditional construction processes cannot compete.

 

At the heart of DfMA is early planning and investment – both financially and in terms of resourcing. In-depth up-front speculation and analysis of potential issues provide clarity and greater certainty. That insight and visibility of progress, from every dimension of the Building Information Model all the way to the factory, are hugely valuable to clients and constructors alike. They instil confidence in the ideas, methodologies and programme, with concerns addressed before on-site work starts.

Dagenham Park Church of England School, UK

Dagenham Park Church of England School, UK

People think about DfMA in the context of buildings, but there is enormous potential to introduce it beyond civil engineering and construction. It is completely foreseeable that modular assembly could inform the build of facilities for electricity and power generation and other utilities. Laing O’Rourke has already, for example, applied DfMA to large water-retaining tanks, which have traditionally been constructed by pouring concrete in situ, requiring a longer installation period and a larger team.

 

A wildly contrasting environment to a sewage treatment works, London’s ultra-luxurious One Hyde Park, used DfMA throughout, from the risers to the bathroom pods. In the residential sector, there are exciting possibilities to implement these ideals in densely populated urban environments in mega cities such as Shanghai and Singapore, which are crying out for efficient, economic and attractive modular housing. Really, offsite manufacturing works at any end of the scale.

A number of factors make DfMA an especially suitable solution for schools and Private Finance Initiative (PFI) projects, principally the reliability and robustness of the finished product and the reduction in noise during the build process, which suits such sensitive environments. Likewise its flexibility is a major advantage: walls and columns can be repositioned, and layouts adjusted. If necessary, a school can be easily transformed into a council office block, which could be modified into a commercial unit.


DfMA produces precast and preassembled buildings and their component parts – from columns, beams and walls to sleepers, cladding and building systems – to a cost, time and specification with which traditional construction processes cannot compete.


 

In rural New South Wales, Australia, the Federal Government’s BER (Building the Education Revolution) programme required more than 300 schools to be built in 18 months. It sounds an impossible task, but with in-depth early planning, you can have one school built, delivered from the factory to the site, and installed on the foundations within a week.

While DfMA is not yet a broadly familiar concept in Australian construction, it has proved to be a highly innovative solution to the many problems of working in remote areas. Firstly, doing the preparatory work in factory conditions overcomes the very real challenge of a lack of qualified and appropriately skilled local tradespeople. For example, in the Pilbara, a resource-rich region in Western Australia, infrastructure project sites might be hundreds of kilometres from the nearest city.

Equally, extremes of weather – from baking heat to tropical cyclones to flooding – can bring work to a stop and present safety risks to our workforce. DfMA minimises the amount of work that needs to be done in these conditions.

On this basis, employing DfMA sounds like common sense. It is. But it remains a far from widespread practice – in some markets it is groundbreaking – and we are challenged by a limited awareness and experience of the concept, and a reluctance to acknowledge the value it can add versus more traditional lowest-price decision-making. Gradually, clients are acclimatising, but it is a massive cultural shift and it is our job as engineers to persuade, educate and reassure.

In sectors such as energy and aerospace, these principles have been common practice for ten or 15 years. Therefore, just imagine what a game-changer it would be if it became the first-choice process across the construction industry.

About the authors:

In Laing O’Rourke’s Engineering Excellence Group, Dr Phillip Cartwright is the Electrical Engineering Discipline Lead and Dr Gavin Davies is the Mechanical Engineering Discipline Lead. Dr Cartwright is the former Head of Electrical Power and Control Systems for Rolls-Royce and Dr Davies worked with Arup for 17 years, specialising in the investigation and development of energy-efficient solutions.