In Britain, we are at a crossroads in the way we deliver housing and infrastructure.
While there is a political will to see more homes built at speed using modern methods of construction, the construction industry needs to show it is serious about adopting manufacturing-style methods.
This could be through the use of a design for manufacturing and assembly (DfMA)-led model, or through a volumetric process (the production of units in controlled factory conditions that are transported to sites).
Given the collapse of Carillion and the Grenfell Tower tragedy, there is no doubt we have to change the industry’s delivery model to build better quality housing on time and at speed. Even when we want to build in a fully volumetric way, this has to begin with DfMA: making the parts of a home easier to manufacture and assemble, while also creating an efficient procurement framework.
Understanding delivery failure
In many instances, housing delivery relies on a design-and-build model. However, this has increasingly become a ‘risk cascade’ rather than a method that places design responsibility with the right party to drive innovative solutions.
This model often leads to the main contractor losing control over the outcomes it desires, in terms of both time and quality.
The conventional approach to risk and margin often forces clients to pursue the cheapest offer. These competitive tendering-led procurement models also tend to ‘close the books’ and provide clients with less clarity over what they are procuring. Without the ability to open-source standard components and systems from multiple providers, procurement models can stand in the way of progress and wide-scale DfMA adoption.
With volumetric construction, this dynamic becomes even more important. Traditional procurement models can impair communication within the supply chain, when in fact clients and designers actually require a deep understanding of the process.
DfMA involves standardising components for manufactured homes as the first step towards a more efficient procurement and construction model.
“A DfMA approach can improve the certainty of a project’s outcome, reducing waste, time on site and construction costs”
Standardisation requires fewer unique parts, which reduces complexity and labour intensity during the assembly process. This also translates into reduced assembly times and more certainty around build programme and cost.
The need for a more efficient procurement process is all the more pressing due to the sector’s reliance on an ageing workforce and migrant labour.
An uncertain post-Brexit world will likely worsen the industry’s skills shortage while driving up labour costs, which must be offset by a new and improved delivery model. DfMA in the construction procurement model can offer valuable productivity gains after the UK leaves the EU.
A DfMA approach can improve the certainty of a project’s outcome, reducing waste, time on site and construction costs while enabling better end-product quality assurance.
Construction has been slow to respond to modernisation incentives in the past. DfMA can help in pushing digital assembly and machining capabilities, as well as slashing the cost of component parts.
This is the first step in creating more integrated, digitally-led delivery models.
Neil Brearley is a director at Cast