How do I calculate the carbon footprint of an aluminium window per square metre?

The aluminium section is most of an aluminium window: weigh the profiles per square metre and use the extruder's per-kg figure. Add glass, gaskets and hardware, then the shop's cutting and assembly energy divided by area made.

Bought-in parts

• Extruded aluminium profiles, powder coated or anodised.
• Single or double glass units.
• Gaskets, rollers and locks.

Fabrication

• Cutting and machining centres.
• Crimping or screw joints.
• Glazing and packing.

Per sq m

Report per square metre by system. Ask the extruder whether the billet is primary or contains recycled metal.

Worked example: aluminium window unit per sq m (one month)

• Electricity: 6,000 kWh x 0.710 = 4,260 kg CO2
• Window area made (sq m): 2,000
• Plant total: 4,260 / 2,000 = 2.130 kg CO2 per sq m
• Add aluminium profiles and glass for the full figure

Inputs are illustrative; use your own bills and production records.

What Senseible does here

Senseible reads the plant's electricity bills (CEA grid factor 0.710 kg CO2 per kWh, CO2 Baseline Database version 21.0) and fuel invoices (IPCC 2006 defaults) into a fingerprinted Scope 1 and 2 record, the plant-level input to a per-unit figure. Bought-in materials go to the supplier evidence trail; product reports are self-declared drafts.

• Product carbon footprint calculator
• Are aluminium windows covered by CBAM
• Aluminium extrusion footprint
• Aluminium industry

Sources: GHG Protocol Product Standard, ISO 14067:2018, Carbon footprint of products (iso.org), IPCC 2006 Guidelines, Volume 2 Energy (fuel defaults), CEA CO2 Baseline Database, version 21.0

Last reviewed 2026-10-20.