With the majority of the value add for structural steel already occurring offsite – in some cases up to 90% – the structural steelwork sector is well placed to be an early adopter of these new approaches.
Key to the success of this approach will be the ability to lock down the complete design. The current construction delivery model does not allow the design to be fixed and drives late changes to design driven by individual sub-contractors as they are engaged. This lack of design certainty is the biggest issue facing steelwork contractors today and one of the largest drivers of cost. BCSA believes late and incomplete design, design errors, and ongoing design changes could currently add up to 15% – 20% in cost to a construction project.
For a platforms approach to be successful, the construction delivery model will have to become collaborative, incorporate early engagement, and demonstrate a high level of coordination and integration. Fixity of design and early engagement of subcontractors would be a significant positive change for the construction sector, even on a structure by structure basis.
While the structural steelwork sector already commonly uses a narrow range of section sizes and three standard connection designs, as well as generally using one standard bolt size, the overall building or structure design is sometimes so bespoke that the standard components and designs are unable to be utilised as often as they could be.
A balance does needs to be struck between over and under application – there is the risk of over application where the benefits of the approach start to get lost. If a platforms approach standardises more than is practical, it may be that the building design becomes less efficient than other design solutions, including offsite manufacturing or traditional techniques.
In its early stages, a platforms approach is most likely to be an alternative to both modular and panelised off-site build systems designed for; for example, student accommodation, low-rise hotels and low-rise residential type structures. This is due to their regular grid, repetitive design and limited number of storeys.
While a platforms approach itself will not necessarily be the optimum solution for all buildings and infrastructure projects, the principles of fixed or standardised design and inter-operability provide a solution for many buildings and will have wider benefits in effecting positive change.
BCSA President & Sales Director Cleveland Bridge