Recyclability (of glass) has become a mainstay in contemporary AEC discourse. There are some serious challenges to it that should not be overlooked; one driving element behind the topic is, of course, the European Green Deal with its taxonomy forcing the (glass) industry to rethink both: the embedded carbon of their products and the energy-intensive way they are produced1. As a repercussion of these factors, we see a decreasing amount of demand for raw materials. Furthermore, 2030, the year in which the European Union committed itself to reduce emissions by at least 55% from levels in 1990, is just around the corner2! There is no time to waste.
Cover image: © Cristian Bortes
Considering how pressing the issues are, it is quite astonishing that, although established in the 1980s, the concept of “urban mining” has only recently come to the fore. The theory behind it is quite simple: turning former waste into future value. This change in mind-set, that the pre-existing built environment can have multiple lives and thus becomes part of a continuous, natural process of erecting and dismantling is momentous and will affect the entire construction industry. It has widespread implications with regard to prefab builds, easyto take apart components, measuring the environmental impact of materials in their urban context and during their lifetime, valorising the monetary value of the “used” or rather “existing” materials, buying products and leasing services.
The importance of recycling and retrofitting is validated by the European Construction Industry Federation, “investment in renovation represents almost 30% of total investment in construction. Having proven to be the least volatile segment over the last decade renovation and maintenance have served as a stabiliser in the aftermath of the financial crisis from 2009.”3
It seems that we are teetering on the edge of a paradigm shift. But the pragmatic question still remains – how do we get the ‘once used’ installed glass (post-consumer cullet) and transfer it back to our floats? To put the required scale into perspective: Saint-Gobain’s largest float plant in Cologne, Germany, produces up to 1000t of glass every day, 365 days a year. Having committed ourselves to manufacturing all our flat glass using 50% cullet by 2050, it is quite obvious that we cannot provide the necessary daily amounts by simply collecting “some” old windows or façade glass.
Saint-Gobain has, for several years, led the industry in the recovery and use of post-industry and post-consumer glass cullet. Initially, this was on a project-by-project bases, however lately (and ongoing), partnership networks have been established with customers and industry partners. In the following article, we take a look at some examples of this continuing engagement.
Among one of the first projects was Lloyd’s of London. In 2010, Lloyd’s decided that it required more daylight and improved views from the iconic Richard Roger’s designed building, originally completed in 1987. Some of the patterned glass panes by Saint-Gobain were replaced with clear flat glass and 123 tons of the original glass was removed from the building and sent back to our float in Eggborough for remelting.
Additionally, some of the patterned glass was reused; the panels were cut into the new required size, and installed back or stored for any replacements required in the future. Some of the “off cuts” were also used in furniture designs for the building, such as tops for coffee tables. The work on Lloyd’s demonstrates re-use and recycling of glass at the highest standards and with minimum environmental impact. The entire project was followed up by Arup.4
The former SAS Headquarters in Frösundavik, north of Stockholm was recently completed. For Saint-Gobain Building Glass, it started as an “ordinary” specification project (5,000 m² of COOL-LITE® XTREME 70/33 II on DIAMANT processed by Saint-Gobain Glassolutions BALTIKLAAS) that quite soon developed itself into one of the largest glass recycling projects to date. Built in the late 80s, this 55,000 m² large complex for 2,000 employees needed an overall refurbishment. But what do you do with the glass of the old façade?
Through engagement with all project stakeholders involved, the glass was dismantled by Swedish façade designers ScandiFront, broken and sorted by Ragn-Sells (a well-known waste management, environmental services and recycling company) and transported with a special inloader to the Saint-Gobain float in Torgau, Germany5. Additionally, Research Institutes of Sweden (RISE) was heavily involved, and made a scientific follow-up on circular use of flat glass from Sweden.
The most pertinent question remains: “Does it pay off?” The definitive answer is, yes, especially in terms of reducing a projects’ commercial as well as CO2 footprint. Consequently, Ragn-Sells, together with Saint-Gobain Glass Germany, will further develop their involvement in glass recycling by establishing a strong Swedish network of glass collecting locations.
Similarly, Saint-Gobain Glass Bâtiment France is initiating a nationwide network of partners that dismantle, collect and do treatment of glass waste from facades. Seven partners have already been qualified, and more are going to be qualified in the coming months. Besides a strong commitment to closed-loop, key specific requirements for becoming one of those partners are mandatory: the integrity of glass during all the steps from dismantling to the treatment of glass as a first condition needed to generate float-grade cullet in a defined quality, but also well-fitted stillages and adapted logistics, and the ability to deal with both single and double glazings and even the materials of the frames (PVC, aluminium, wood, etc.).
Saint-Gobain will not only take the cullet but will provide additional services like coaching of the different stakeholders, technical support of the treatment process, and the animation of the qualified partners. The first results are quite encouraging: starting from some 5,000 old windows (87 tons of recycled glass) in 2019, Saint-Gobain Glass France and its partners collected more than 15,000 old windows in 2020 (280 tons of recycled glass) and even more in 2021: more than 1000t of recycled glass, which is an equivalent to 50 000 windows… a successful beginning of a new era … and we can’t wait to see next year results!
Furthermore, similar initiatives and partnership networks are being established in other countries. This progress should inspire us all and task the industry to further pursue a circular economy in future endeavors. Recycling glass will become mandatory in the future. The benefits are not solely in reducing our CO2 footprints; urban mining has positive spill-over effects that will generate opportunities in business development and employment. It is now up to us to decide how we continue; starting today, the opportunities to contribute positively to the world are available. Saint-Gobain is committed to a greener, sustainable future and we will continue to innovate, progress and develop initiatives to ensure this ideal is upheld. Let’s turn (glass) waste into value for the benefit of us all. Please contact us for further information and support.
This article was originally published in IGS Magazine’s Autumn 2021 Issue – Glass Retrospective: Read the full Magazine here for more thought-leadership from those spearheading the industry
(1) https://ec.europa.eu/info/businesseconomy-euro/banking-and-finance/ sustainable-finance/eu-taxonomy-sustainableactivities_en
(2) https://ec.europa.eu/clima/policies/ international/negotiations/paris_en#tab-0-0
(4) https://www.arup.com/perspectives/ publications/the-arup-journal/section/thearup-journal-2011-issue-2
(5) https://www.ri.se/sv/vad-vi-gor/projekt/ okad-cirkular-anvandning-av-planglas
Educated as an architect and urban planner at the RWTH Aachen University in Germany, Andreas Bittis was editor for ARCH+ and a freelance journalist for various architectural magazines on and offline. Consequently, he worked in several architectural practices; Rhinescheme (Beijing) ingenhoven architects, (Dusseldorf, Sydney, Singapore) and Eller + Eller Architekten (Dusseldorf, Berlin, Moscow) to name a few, as project manager in different domains. With this background he joined Saint-Gobain Building Glass in 2012 as Architectural Specification Manager working not only on advising architects and façade consultants but also on topics like Sustainability and BIM. In 2015 he joined the German marketing team as Product Manager for all coated glass and Market Manager for the glass façade projects. Most recently, Andreas joined the Business Unit Façade as Market Manager in Paris