Screenshot of 3D modelling using Revizto.
Involving builders and subcontractors earlier in design can help reduce rework, waste and carbon emissions, says Hawkins new business manager for the north Olivia Pearson.
“There’s always going to be value in environmental savings through material selection but the largest sustainability wins I’m seeing in construction right now aren’t coming from what we build with – they’re coming from how well we plan before we build at all,” she says.
“Those gains happen before the first shovel breaks ground and their potential to reduce waste and carbon emissions surpasses almost any other single action.”
Rework, which involves redoing work because of design changes, errors or poor coordination, carries significant costs. Overseas research from the US Construction Industry Institute estimates these at around 5% of a project’s value, with some studies putting the figure as high as 20%.
Pearson says she has seen the consequences during her 25 years in the industry. “I’ve seen other companies’ projects sent back to the drawing board mid-construction – that’s waste no amount of clever materials selection can offset.”
She says involving builders and subcontractors early enough for their experience to shape the design, rather than just its delivery, is critical. Building information modelling (BIM) platforms enable multiple parties to plan collaboratively, test approaches and sequence construction before work begins on site.
A study published in the Ain Shams Engineering Journal modelled BIM-based design coordination on a sample construction project and reported a 15% reduction in embodied carbon alongside a 10% decrease in cost. While comparable New Zealand studies are harder to find, Pearson sees no reason similar benefits would not apply locally.
Revizto digital collaboration software is standard across Hawkins projects, from commercial towers to airports, universities and hospitals, Pearson says. Some projects generate as many as 12,000 A3 PDF drawings. Managing these digitally reduces printing and helps ensure field teams work from current drawings rather than superseded plans.
Since the start of June, Hawkins has recorded more than 300 unique users on the platform, including over 200 from external clients and subcontractors, generating 8966 interactions. Based on an estimated five minutes saved per interaction, the company calculates a saving of about 747 hours.
“It’s easy to see how saving hundreds of hours of staff time can translate into tens of thousands of dollars saved over a project’s lifespan,” says Revizto chief innovation officer Jason Howden.
“However, the largest benefits come from BIM’s ability to mitigate the risk of time and cost overruns through planning and scheduling, which can also translate into reduced emissions through projects finishing earlier than they otherwise would.”
Pearson says uptake of digital collaboration tools and BIM has not grown as quickly as she would like across the sector.
“In a procurement environment that often rewards the lowest up-front price, these tools can be the first thing cut to trim a tender. That’s a false economy – it just shifts the cost into the asset’s operating life instead.”
Hawkins uses 4D BIM modelling to combine model geometry with its construction programme and methodology, enabling teams to visualise the installation of complex services and seismic restraints.
“As AI adds another layer to digital twins, I expect models to move from reference tool to core contract document,” Pearson says.