PET Bottles - Potential world first in waste stream upcycling at the V&A Waterfront
Photo Cred: V&A Waterfront

The recycled PET bottles are called eco-bricks. To the best of their knowledge, the Ridge is the first large commercial building in the world to build like this.


Western Cape, South Africa (14 March 2020) – A new project broke ground at the Portswood District of the V&A Waterfront last year. The project upcycles a significant stream of plastic waste using sustainable methods. The project in question is the Ridge Building, a bespoke eco-building currently under construction. It will serve as the regional office of a multinational client, Deloitte.

Mark Noble, Development Director at the V&A Waterfront, says that recycled beverage bottles are being used as ‘eco-bricks’ on site. Made from polyethylene terephthalate (PET) plastic bottles, these include ‘Coke’ 2-litre bottles. The eco-bricks will be used as void formers in the concrete slabs in the central toilet areas on each floor of The Ridge.

From a structural perspective, forces run along the outside of the structural member of a building. This useful characteristic has allowed, for example, the safe usage of bricks with holes in the middle.

So the core of a concrete structural element plays little role in imparting strength, but a hollow or near-hollow core can remove a tremendous amount of weight from the building. Consequently, less concrete and structural steel may be used to support the additional weight of the building than would be the case without the void-formers.

“Often, builders incorporate void-forming materials into concrete slabs. These are of a much lower weight than concrete. They are sometimes made of expanded polystyrene (EPS). Under normal loads, these voids do not undermine the structural strength of the slab. But they offer many other benefits, which is why we use them.

“The recycled PET bottles are called eco-bricks. To the best of our knowledge, the Ridge is the first large commercial building in the world to do this,” says Noble.

Void formers are more than a significant opportunity to lower the material cost of the building. Void formers also dematerialise the construction. In green building technology, this reduces the embodied carbon and energy ‘footprint’, meaning lowering its environmental impact. Less usage of materials such as concrete and steel also reduces building material waste recovered at the end of the structure’s service life.

According to the Green Building Council of South Africa (GBCSA), the construction and operation of buildings globally were found to contribute in excess of one-third of all greenhouse gases. Hence any methods that reduce the greenhouse gas contribution of a building are of benefit in the battle against climate change and environmental pollution in general.

From excavation to topping-out, the positive contribution of voided slab weight reduction alone delivers sustainable advantages for property owners, designers and builders.

A commonly used void forming material is EPS, most often formed into shapes or profiles using virgin polymer material. This, however, does not contribute to environmental benefits and consumes plastics made from fossil fuels.

Potential world first in waste stream upcycling at the V&A Waterfront
Photo Cred: V&A Waterfront

Sometimes, voided concrete slabs use recycled materials, not only generating far less waste material when scrapped one day, but capturing a waste stream which would otherwise have been sent to landfill, or reprocessed at a cost.

The bottles are filled to constant density with waste plastics. This waste includes chip packets, candy wrappings, shopping bags and waste generated on-site. The eco-bricks were donated by community volunteers and scholars from Cape Town’s suburbs, and quality control is undertaken on-site by the main contractor. The checked bottles then get used as void-formers at the Ridge.

“Together with our various other established recycling programmes, which include a substantial quantity of the building waste from the SILO project being re-used, these techniques make a vital contribution to the circular economy. The is what we term ‘Our Normal’, a bold step into participating in this new economy and the environmental challenges we face”, he concludes.

Don’t ever miss the Good Things. Download the Good Things Guy App now on Apple or Google
Have something to add to this story? Share it in the comments or follow GoodThingsGuy on Facebook & Twitter to keep up to date with good news as it happens or share your good news with us by clicking here
Click the link below to listen to the Good Things Guy Podcast, with Brent Lindeque – South Africa’s very own Good Things Guy. He’s on a mission to change what the world pays attention to, and he truly believes that there’s good news all around us. In the Good Things Guy podcast, you’ll meet these everyday heroes & hear their incredible stories:
Or watch an episode of Good Things TV below, a show created to offer South Africans balance in a world with what feels like constant bad news. We’re here to remind you that there are still so many good things happening in South Africa & we’ll hopefully leave you feeling a little more proudly South African.

Facebook Comments

About the Author

Brent Lindeque is the founder and editor in charge at Good Things Guy.

Recognised as one of the Mail and Guardian’s Top 200 Young South African’s as well as a Primedia LeadSA Hero, Brent is a change maker, thought leader, radio host, foodie, vlogger, writer and all round good guy.

Leave a Reply

Your email address will not be published. Required fields are marked *