In a New Zealand-first, Hawke’s Bay has been piloting a new way to tackle one of the building industry’s most persistent waste streams – plasterboard.
Led by Hastings District and Napier City councils’ waste minimisation lead Geoff Gibson, the trial is a partnership with Winstone Wallboards, Central Environmental, and local building supply merchants: Carters, ITM, Mitre 10, and Placemakers.
Together, they’ve rolled out a straightforward but highly effective bag-based system for collecting clean GIB® plasterboard offcuts. Plasterboard is made from a core of gypsum (calcium sulphate) sandwiched between layers of heavy-duty paper. Depending on its use, it may include additives such as fibres, foaming agents, or moisture-resistant treatments. It’s predominantly used for interior walls and ceilings in buildings.
Since the trial began in May this year,13,938 kilograms of plasterboard waste have been diverted from landfill – instead bagged up and transported to Feilding by Central Environmental.
There, the contents are weighed and inspected for contamination before being processed through a specially modified two-stage shredder. The components are separated, with the paper sent for composting and the gypsum bagged and shipped back to Winstone Wallboards to be re-manufactured into new GIB® plasterboard.
The initial loads were 100% free of contamination, a critical success factor for closed-loop recycling, said Winstone Wallboards sustainability manager Jamie Rodriguez.
“It was exactly the result we were aiming for, and great to see it play out in real-world conditions.”
What sets this trial apart is its simplicity and how easily it integrates into everyday site practices, said Mr Gibson. Builders receive pre labelled bags with their plasterboard deliveries, making it easy to separate offcuts on-site without disrupting workflows.
For GIB plasterboard installer companies like Atlas Fibrous Plaster, the benefits are immediate.
“It’s been really easy to get into,” said foreman, John Reeves.
“The bags come with the GIB plasterboard delivery and we just chuck the offcuts straight in as we go. There’s no extra hassle, and it feels good knowing it’s not all going to landfill. We’re proud to be part of something that’s making a difference, and in these tight trading conditions, it saves us money.”
Feedback from builders and merchants is helping refine the trial and strengthen the case for making it permanent. Participants also receive data showing the recycled weight per bag, which can be used for waste reporting or identifying areas for improved efficiency in their business.
More than just a recycling initiative, this project signals a shift towards smarter, circular solutions in the construction industry. Its real strength lies in collaboration; merchants and councils working together to solve a complex waste challenge with no existing roadmap.
Looking ahead, the group hopes to see more builders using the bags until it becomes standard practice across the industry.
Construction and demolition waste makes up a significant portion of what ends up in landfill. According to the 2024 SWAP (Solid Waste Analysis Protocol) report, this waste accounts for eight per cent of Hawke’s Bay’s total waste tonnage. Nationally, BRANZ estimates that 40 to 50% of New Zealand’s total waste to landfill is from construction and demolition sources.
Based on data supplied by Winstone Wallboards, it’s estimated that up to 840 tonnes of plasterboard waste generated in the region each year is potentially recyclable.
A short video showing the full journey, from building site to remanufactured product, can be viewed here https://www.hastingsdc.govt.nz/services/rubbish-and-recycling/waste-at-work/#wastegib.
