Carbon footprint and material sourcing
Design & Technology · Key Stage 3 · The School
What a carbon footprint measures
A product's CARBON FOOTPRINT is the total greenhouse gas released across its whole life. Digging up raw materials. Processing them. Making the product. Moving it. Using it. Throwing it away. Looking at just one stage, such as disposal, can miss where most of the real impact happened.
How sourcing affects the footprint
Where and how a raw material is dug up matters. Mining a metal ore and shipping it halfway round the world before processing adds transport emissions a more local source would not. A material that needs high-temperature processing, such as some metals, usually carries a bigger footprint than one processed at lower temperatures, such as many timbers.
Weighing sourcing against other factors
A locally sourced material is not automatically the better choice overall. It might wear out faster, meaning the product needs replacing sooner. That can add up to a bigger total footprint than a material shipped from further away but built to last. A real evaluation weighs sourcing distance AGAINST how long the material lasts, how well it performs, and its own processing footprint — never distance alone.
A furniture maker needs timber for a table. Option A is grown locally, within 50 miles. But it is a soft wood that dents and wears out within a decade of regular use. Option B is a hardwood, shipped from much further away. But it is dense enough to last several generations with basic care. Sourcing distance alone would favour Option A. But Option A's short life means the table may need replacing two or three times over the years Option B's single table would still be in use. Each replacement carries its own full manufacturing and transport footprint. Weighed over the table's real lifetime, not just at the point of purchase, Option B can genuinely carry the smaller total footprint, despite travelling much further to reach the workshop. This is exactly why "buy local" is a real, useful factor — but never the only one that decides an honest sourcing choice.