CARBON CLAIMS NEED CLARITY

Senior Architectural Systems is calling on the fenestration industry to move beyond top-line figures to a more evidence-based approach that gives specifiers more accurate data.

As part of its ‘What You See Is What You Spec’ campaign, Senior Architectural Systems is reinforcing the clarity of its environmental information and calling on the industry to adopt the same transparent approach.

This follows Senior’s publication of product-specific Environmental Product Declarations (EPDs) for its aluminium doors, windows and curtain wall systems, which challenge the traditional format to provide more accurate data.

Senior’s EPDs include the environmental impact of all system components, including thermal breaks, gaskets and fixings, as well as fabrication and delivery to site via Senior’s fabricator network.

The energy-intensive extrusion process is also accounted for, but the glazing has been omitted. This is because glazing, which is not typically supplied by system houses, can artificially lower the carbon figure for the aluminium system. Senior argues that glazing should always be reported separately through its own EPD.

Senior believes specifiers should only be given accurate and useful information, and this project is being headed up by the manufacturer’s UK sustainability lead, Luke Osborne. Under his stewardship, Senior is reframing the way it communicates information about its low-carbon aluminium to provide more detail and context that empowers specifiers.

Senior would like to see a move away from quoting carbon figures relating to aluminium billets in isolation, as this doesn’t account for the extrusion and profiling process and doesn’t reflect the products actually installed on site.

For its part, Senior is keen to provide greater clarity around its own aluminium extrusion processes and how that affects the billet figure. The company offers two options – its standard aluminium, known as ReAl 4.0, and its lower-carbon option, which is available on request, ReAl 2.0.

Senior’s standard ReAl 4.0 aluminium has a billet figure of 3.5kg CO₂e/kg and an extrusion figure of 0.75kg CO₂e/kg, giving an overall carbon footprint of 4.25kg CO₂e/kg for mill finish aluminium profiles.

ReAl 2.0 has a billet carbon footprint of 1.61kg CO₂e/kg which, when added to the 0.75kg CO₂e/kg figure for the extrusion process, gives an overall figure of 2.36kg CO₂e/kg for mill finish aluminium profiles.

Osborne said: “As carbon figures relating to aluminium billets alone don’t give an accurate picture of the products installed on site, the extrusion process must be factored into any carbon calculations, as well as all the individual components that make up the specific system.

“Otherwise, there are discrepancies in terms of what has been claimed and what is true. With many public sector projects now engaging with carbon auditors to check for this very issue, the need for full transparency is not only an ethical matter but also a commercial one.

“Our EPDs specifically address this problem and hopefully buck the trend to create a more accurate benchmark for how the environmental performance of aluminium fenestration systems is positioned and communicated. I firmly believe EPDs should be open to interrogation, audit and robust scrutiny, making them a useful resource for specifiers rather than simply a marketing or sales tool.”