Roof Rack (aluminum)

Material Composition Assumptions

The assessment covers a complete roof rack system weighing approximately 3 kilograms total. The primary component consists of aluminum alloy rails and crossbars manufactured from 6061-T6 grade material, representing roughly 2,700 grams or 90 percent of the total weight. Stainless steel fasteners including bolts, clamps, and mounting hardware account for 240 grams or 8 percent of the system mass. Rubber dampening pads and protective components comprise the remaining 60 grams or 2 percent of the assembly weight.

Manufacturing Geography

The majority of aluminum roof rack production occurs in China, where approximately 60 percent of global aluminum smelting capacity operates using coal-dominated electricity grids with an average intensity of 555 grams of CO2 per kilowatt hour. Chinese manufacturers benefit from integrated supply chains that combine raw material processing, extrusion capabilities, and final assembly operations within proximity to major automotive markets. The high grid carbon intensity significantly elevates the embodied emissions compared to production in regions with cleaner electricity sources.

Regional Variation

Manufacturing Region	Grid Intensity	Estimated CCI Score	Adjustment vs Default
China	555 gCO2/kWh	12.0	Baseline
Middle East	450 gCO2/kWh	10.8	-10%
Eastern Europe	380 gCO2/kWh	9.2	-23%
North America	280 gCO2/kWh	6.8	-43%
Northern Europe	180 gCO2/kWh	4.9	-59%

Provenance Override Guidance

1. Submit verified recycled aluminum content percentages with third-party certification demonstrating the proportion of post-consumer or post-industrial scrap material used in production.

2. Provide electricity source documentation including renewable energy certificates, power purchase agreements, or grid emission factors specific to the manufacturing facility location.

3. Submit transportation mode and distance data covering the movement of raw aluminum from smelter to fabrication facility and from fabrication to final assembly location.

4. Document aluminum alloy specifications and any secondary processing requirements such as heat treatment, surface finishing, or additional machining operations that affect energy consumption.

5. Provide end-of-life recycling infrastructure data demonstrating the availability and efficiency of aluminum recovery systems in target markets.

Methodology Notes

• The CCI score represents cradle-to-gate emissions including raw material extraction, processing, manufacturing, and transportation to point of sale
• Scope 3 emissions dominate at 98 percent due to energy-intensive aluminum smelting processes occurring upstream in the supply chain
• The functional unit covers one complete roof rack system capable of supporting standard cargo loads as specified by automotive manufacturers
• Vehicle use phase impacts from increased aerodynamic drag are included but represent a minor component at 2 percent of total lifecycle emissions
• Exclusions include end-of-life recycling benefits, installation hardware specific to individual vehicle models, and optional accessories such as cargo boxes or bike mounts
• Data gaps exist around specific alloy compositions and the carbon intensity variation between different aluminum suppliers within the same geographic region