James Hindes is managing director for the Kier Aviation and Defence business. Here, he talks about the opportunities that exist in airport construction productivity through an industry-wide adoption of design for manufacture and assembly (DfMA) principles.
“Design for manufacture and assembly (DfMA) is when a manufacturing mindset is used on the design and construction of buildings and infrastructure. A DfMA approach draws on a range of suppliers and systems to design a scheme using manufactured components for ease of assembly on site. This solution can deliver improved efficiencies through a use of repeatable components and processes, achieving a higher quality product in less time at better value.
The examples of DfMA in our industry are very disparate and tend to only happen when the project team is fully aligned top to bottom, from client to cost consultant, designer, contractor and specialist contractors. DfMA optimum design solutions do exist amongst the design community and the benefits are there for the taking, however these will only be realised where there is a joint desire to collaborate.
There are a number of spaces and components that are repeated throughout all airports across the UK whether they are fixed links and nodes, circulation spaces, risers, toilet modules, risers or primary corridors to name a few, making them perfectly suited for DfMA. Over the years I’ve observed and been fortunate enough to deliver some great examples of DfMA solutioned buildings, one example being the construction of Terminal 5C constructed at Heathrow Airport some eight years ago.
At Terminal 5C, the client, designer and contractor collaborated from the outset to design and assemble the 12 fixed link bridges, nodes and passenger boarding bridges offsite as a kit of parts.
The benefits of this approach were remarkable. The on-site programme time went down from 16 weeks to 4 weeks per node, we significantly reduced adjacent stand down time, improved tolerances, better quality and there were far less trades on site. This example could instantly be adopted as a standard approach, replicated and rolled out across all new airport infrastructure projects.
Other benefits of DfMA are:
- Greater predictable installation. More parts mean a greater potential for assembly problems and a DfMA approach looks to eliminate components. It also requires tolerances among various trades to be agreed upon at the early design stage. Therefore, when components do arrive on site, they all interface correctly.
- Higher quality components. Since much of the project assembly is done in a clean factory environment, the end product can be of higher quality than what’s produced onsite. Costs are saved through less construction time and reduced lifetime maintenance.
- Improved worksite safety. This prefabrication focus means that fewer trades are required onsite, and the working environment is more predictable, which leads to improvements in both safety and logistics.
Benefits also carry over to the building’s operation and maintenance, including:
- Ongoing maintenance. This holistic design approach gives consideration to providing easy-access for maintenance or end-of-life component replacement.
- Accessible building information. The DfMA approach relies on the use of design modeling, meaning it is simple to pass building information on to the owner and operations team. Owners then have information guiding decisions on preventive maintenance and predictable insight into the asset’s performance through its life.
With the clear benefits DfMA can bring to projects, I sense there is an industry-wide assumption that the solution will solely come from the main contractor or the specialist contractor. From my experience, it is clear that DfMA will only happen when there is a design on the table that all parties responsible are confident with and are happy to commit to delivering. This is a fantastic opportunity for the design community to collaborate and lead on providing a suite of standardised solutions that are based on DfMA principles.
It is good commercial practice for a cost benefit analysis to be conducted to ensure a DfMA course of action provides value for money. It is equally important to also consider other benefits, such as receiving a facility early as a result of a faster build programme, the reduction of accidents as a result of fewer operatives on site, better quality (factory conditions) and greater programme certainty.
It goes without saying that the principles discussed above could and should apply to all sectors, but this provides a great opportunity for UK airports to pave the way and show the long-lasting benefits of DfMA on projects.”