Offsite construction methods for building are on the rise, but there is concern over a lack of the necessary skills to meet the increase in demand.
In a recent UK survey, 42 per cent of employers with over 100 staff said they expect to be using offsite construction methods more in five years’ time, and all of them said they expected the use of precast concrete panels to increase. In particular, 91 per cent anticipated the use of precast concrete frames to rise.
The benefits of offsite construction include:
- Lower assembly cost
- Higher quality and sustainability
- Shorter assembly time
- Increased reliability
- Improved health and safety
- Less disruption to the site’s neighbourhood
Australia currently lags behind the UK in this area, with modular construction and pre-fabrication representing just three per cent of Australia’s $150 billion construction industry.
But the benefits are potentially huge. In the UK the use of “flying factories” by Skanska and Costain for phase one of the Battersea Power Station housing redevelopment resulted in a 44 per cent cut in cost, 73 per cent less rework and a 60 per cent reduction in time.
In another case, 80 per cent of the Leadenhall Building was constructed offsite by Laing O’Rourke, resulting in a 50 per cent reduction in deliveries to site. The same was true of Vinci’s Circle Health building in Reading, England, resulting in a 20 per cent program reduction and a 28 per cent cost saving.
Half of the clients of building companies expect offsite construction only to increase, according to the report. But if this is to happen, from where will the skills to meet this demand come?
The report outlines six key skills areas related to offsite construction:
- digital design
- offsite manufacturing
- site management and integration
- onsite placement and assembly
Increasingly, workers will need these skills to move between offsite and onsite environments and so the training for these six areas must evolve to meet the changing demand, says the Construction Industry Training Board (CITB).
Of businesses expecting to use offsite construction over the next three to five years, 38 per cent told the CITB they believed they will need new or significantly improved skills within their workforces. Handling and assembly skills are those most in demand, with 81 per cent of employers citing them.
Seven in 10 also mentioned skills relating to the operation of powered equipment, health, safety and welfare, site preparation, disposal of waste, team working and quality control.
Mark Farmer, author of the 2016 Farmer Review on the future of construction for the UK Government, says there is a need to attract high quality talent from among the new generation of students who aspire to a very different, digitally led career.
In the foreword to the new report by CITB, he says we need a two-pronged approach: “Firstly, adopting more integrated precision engineered ‘pre-manufacturing’ techniques, in turn supported by growing client led demand. Secondly, to evolve a new skills and training landscape alongside the more traditional pathways that enables and supports the implementation of innovative techniques and technologies.”
So let’s take a closer look at the emerging required skillsets:
Designers will need a new range of digital capabilities. Arguably the most important is the adoption of 3D digital models with rich data (using Building Information Modelling) so that designs can be robustly tested and agreed in advance of manufacture to avoid costly errors and modifications at later stages.
Aligned to this is the need to integrate the design function into early stage planning with the contractor and client. This is a significant break from the norm and challenges designers to adopt a more holistic approach to their role.
Given that cost saving is one of the key advantages of offsite, the estimating function becomes an even more crucial one in the sector.
Estimators must account for – and have an understanding of – materials used, transportation costs and risk factors.
For offsite projects, the costing model often puts a far higher proportion of the cost at the outset (that is, before being onsite).
But this can deter clients. Being able to make the case for an alternative value proposition is, therefore, vital.
The technical skills required include developing whole life cycle costs, analysing tender documents and contracts, developing tenders, and understanding the use of BIM.
Offsite manufacturing skills
Offsite manufacturing requires technical skills, like welding, joinery, pre-casting and steel fixing, already present in the construction workforce, plus product and process knowledge.
Product knowledge of concrete, light gauge steel, hot rolled steel, open and closed timber frame, cross laminated timber and structural insulated panels are perfect for most factories in the current market.
Many factories use traditional trades, meaning there is still a healthy market for these skills and those who train them.
However, a growing number of companies are moving towards having multi-skilled operatives who are comfortable with a wider variety of tasks and responsible for quality assurance of finished components.
This means that machinists and other multi-skilled operatives would benefit from basic design knowledge to understand what a finished output should look like and to address any issues that might affect assembly onsite.
Offsite logistics requires more patience and control, while the traditional function is frequently “more chaotic”.
Much of this skillset revolves around coordination and integration, so it is important that those involved develop soft skills such as listening and distilling information, as well as problem-solving capabilities.
As with other functions, skills in understanding and using digital models and data become vital here, particularly with regard to planning and project management.
Onsite assembly often relies on pre-existing core “tradespeople” skills. However, additional skills, both technical and soft, are also required, together with those traditional ones.
For instance, a crane operator needs new skills in handling much larger, unstable pre-manufactured loads.
Similarly, ground workers need to work to much tighter tolerances so that foundations match precisely the dimensions of the components being assembled.
Technical understanding of products and materials is a key requirement across all roles.
Quality assurance, process management and problem-solving skills are also crucial competencies for both assemblers and site supervisors.
Adaptability and communication are the key skills for the site management function when
it comes to offsite construction.
The role hinges on being able to integrate onsite and offsite functions in one project. In this sense, soft skills, such as time management, attitudes and behaviours are arguably as important as technical skills.
Digital skills are required in reading and using BIM models, to help with correct sequencing and installation. Quality assurance skills and behaviours are also important.
The way forward
Whereas there will always be a space for onsite construction, at least some offsite construction for a project offers so many benefits that it is bound to increase. The infrastructure and industrial sub-sectors have been somewhat slower to adopt the offsite agenda than housing and office space, but they are expected to catch up.
Steve Radley, director of policy at CITB, says: “The greatest potential currently lies within the housing and commercial sectors, where mass customisation can create the buildings we need more quickly and to higher standards. There are also opportunities to bring the benefits of offsite to large-scale infrastructure projects.
“Successful offsite management hinges on the effective integration of both onsite and offsite functions – and this requires a comprehensive understanding of both aspects,” he adds. For anyone considering starting out in the industry, this is a good message to take on board.
David Thorpe is the author of a number of books on energy efficiency, sustainable building and renewable energy. See his website here.