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The Role of Glass in Sustainable Construction

The Role of Glass in Sustainable Construction

Glass Recycling

In the area of sustainable construction, Metro Glass is a key player in glass recycling in New Zealand. With a commitment to minimising glass waste, Metro Glass has set an ambitious goal of aiding the New Zealand construction industry toward zero glass waste into landfill. The strategy revolves around investing substantially in glass recycling, optimising manufacturing efficiency, and advocating for the repurposing of construction glass waste into various glass-based products, including glass bottles and insulation going into products such as Pink Batts.

When it comes to glass waste from their manufacturing plants, Metro achieves an impressive recycling rate, averaging 99.3% of waste glass being recycled, ensuring all offcuts and unused materials are re-purposed. Their customer take-back scheme is a testament to their proactive approach, ensuring their community of customers also find it easy to recycle their waste glass. The Declare “Red List Free” certification of the glass Metro recycles into insulation and bottles assures that it contains no toxic or harmful ingredients.

Metro Glass is currently supporting work on special technology to enable recycling windshields which have a plastic interlayer in between the two panes of glass. Historically these units were unable to be recycled because of the co-mingled materials.

A man pushing buttons of machine in workshop

Their retrofit business shows their dedication to sustainability, as they replace single glass panes with high-performing double-glazed ones and are one of the few companies who recycle the replaced glass, and also the frames if needed.

However, a lot of construction glass does not get recycled and that is mainly due to sites putting all site waste into one bin which goes to landfill. Where possible, Metro Glass encourage including a glass only bin, which would mean it can be returned to one of the glass recycling plants in Auckland or Christchurch.

For architects and construction professionals, collaboration with forward-thinking companies like Metro Glass can be a meaningful step toward sustainability. Choosing partners who prioritise recycling and environmental responsibility can amplify their impact, driving the industry toward more eco-friendly practices.

Glass workshop with toitu carbon reduce logo

Glass Supply Chain

New Zealand glass usage in construction involves importing flat sheets of glass, which arrive with pre-applied Low E coatings or coloured tints embedded in the material. These imported sheets are then locally processed into various construction products like insulated window units, balustrades, showers, and splashbacks. Metro Glass takes a proactive stance in this supply chain, choosing suppliers who incorporate significant amounts of recycled glass at source. Their efforts ensure that the products they offer are not just high in quality but also environmentally responsible, containing on average 22% recycled content.

A stack of glass in workshop