Aluminium At Forefront Of Circular Economy
Ant Gungor, Business Unit Manager at SFS Construction UK, discusses the company's adoption of a class of aluminium featuring a 100% recycled content for fabricating the majority of its rainscreen subframe brackets
Two full centuries have passed since geologist Pierre Berthier first unearthed the ore which gives us aluminium, close to the small French village of Le Baux. And there is a good possibility that some of the early cutlery, tableware, and other high value items the metal was used to make could still be seeing service in a building structure or other application near you today.
For although the cost of its extraction and processing originally made aluminium a luxury, bauxite remains one of the most abundant resources on the planet - while the comparative ease of recycling means that three-quarters of all the aluminium ever produced is still in use.
In fact, if it were not for the fact that mankind continues to find more diverse applications for the metal, and consumer demand for manufactured goods continues to grow across large parts of the globe, we might well have reached a point where we no longer need to excavate fresh stocks. We can, however, take comfort in the fact that aluminium has proved incredibly versatile and durable, exhibiting excellent strength to weight ratio which sees it outperform most other building materials. Therefore, given construction work and the wider built environment have such a major impact in terms of carbon emissions, the recyclability of aluminium puts it in a class of its own.
Norwegian-based Hydro Aluminium, one of Europe’s biggest producers of renewable energy as well as a major manufacturer, contends that recycled aluminium requires only 5% of the power used to smelt virgin metal.
And this energy efficiency is one of several reasons why SFS Group Fastening Technology has adopted a class of aluminium featuring a 100% recycled content for fabricating the majority of its rainscreen subframe brackets - with stainless steel being available to further improve the thermal transmission characteristics.
Importantly, not only is 6005 grade aluminium produced from traceable scrap aluminium, but it offers excellent strength and durability with its quality being assured by enforcing ‘closed loop’ procedures to monitor the sourcing of waste material. Accordingly, the respected trade body the Council for Aluminium in Buildings (CAB) affirms: “To keep aluminium in the loop, it must be collected and sorted properly.”
Documents on the CAB website highlight 6005 grade aluminium's superior physical and environmental credentials making it a go-to option for structural components, including cladding systems. 6005 and 6005A are appraised on a series of physical characteristics; top of the list being mechanical strength. They offer a significantly higher tensile and yield strength than standard 6063 – making them ideal for heavy duty extrusions such as curtain wall transoms, rainscreen support brackets and walkways. Nevertheless, the leading 6005 grade alloy generates only 4 kg of carbon for each kg produced; compared to around 7kg for some common alloys.
Then, in terms of workability and finish, 6005A provides superior bending properties and mill surface finish compared to 6063 and can produce more intricate profiles. In addition, the alloy of choice for rainscreen applications offers great corrosion resistance, aligning it with Eurocode 9 requirements and broader architectural aspirations.
The discipline that CAB has helped bring to the UK supply chain ensures that the significant amounts of aluminium being salvaged from existing buildings at the end of their lives, or during refurbishment, is forensically sorted and tracked to avoid the mixing of different alloys which could adversely affect performance in reuse. As well as respecting the contemporary construction codes, this also plays a vital part in the transition towards Net Zero.
As referenced in a technical article on CAB’s website, SFS has previously published a White Paper entitled “Sustainability in aluminium rainscreen subframe systems” covering a series of relevant topics including verification of scrap metal streams, bracket design and reuse, to end-of-life strategies.
Overall, SFS is committed to supporting enhanced recycling processes and the value chain across the industry. Meanwhile, on a project-by-project basis, the company’s engineers and technical advisory service are dedicated to assisting customers fine tune system designs so material usage, energy conservation and structural performance are all optimised. For further information, call 0330 0555888 or visit https://uk.sfs.com