McLaren Construction is reckoned to be the first UK contractor to deliver closed-loop recycling of window glass at scale . The recycling is on the refurbishment of 644 apartments at the Chalcots Estate in Camden, where window replacements started in February this year.
McLaren has established the process with Powerday and Saint-Gobain. Powerday collects and crushes the glass; the resulting cullet (crushed glass) will then be recycled back into window glass manufactured by Saint-Gobain.
Saint-Gobain’s target is for more than 25% of its glass to be recycled from dismantled buildings (post-consumer cullet) by 2050, while the proportion currently stands at less than 1%.
McLaren was awarded the contract for refurbishment of four 23-storey blocks on the Chalcots Estate in January 2022. The works include replacement of 24,000 sq m of cladding and 3,496 windows while around 3,500 residents remain in their homes.
McLaren’s pre-construction director for facades, Claire Tribe, explained the challenge. “In principle, glass is infinitely recyclable,” she said, “but we don’t recycle enough of it and we haven’t got to grips with the challenges around higher-grade glass.”
She continued: “To make new flat glass with recycled material you need to start with good quality flat glass. Recycled bottles don’t give you the right quality. It’s not hard to recycle the off-cuts in a factory, but there are extra challenges once the glass has been installed. Windows have to be dismantled and transported without breaking them to avoid any contamination.
“Recycling window glass at scale in this way is essential to providing manufacturers with a reliable flow of material so that they can commit to high levels of recycled content in new glass. What we have been able to do here is connect the circular economy and create capacity in the UK recycling sector for future construction projects.”
As part of the Chalcots Estate refurbishment, McLaren has engaged Alutrade to take the old aluminium window frames for recycling too.
The refurbishment works are scheduled to be completed in November 2024.