How to measure emissions from Materials

What counts as Materials

Materials is the general-purpose category for purchased raw and construction materials that aren't specific enough to sit under Metal, Mineral, Plastic, Paper or Textiles — for example mixed or unspecified raw materials, construction materials, or purchases where only a blended spend figure is available. It's reported under Scope 3 Category 1, in kilograms, tonnes or unit counts where physical data exists, and by spend when it doesn't.

Materials functions as the fallback within the purchased-goods cluster: whenever a specific material category exists — Metal, Mineral, Plastic, Paper, Textiles — use it instead, because material-specific factors are more accurate than the generic materials average. This category earns its place for genuinely mixed or unspecified purchases, particularly in construction, where a single line item might cover several material types that aren't itemised separately, and for cases where only total procurement spend is known. Because it includes a spend-based "average materials" option, Materials is often the honest choice when granular data simply isn't available yet, rather than guessing at a more specific category. As your data maturity improves — for instance moving from a blended construction materials invoice to itemised weights per material — reclassify the more specific portions into Metal, Mineral, Plastic, Paper or Textiles.

What activity data you need

Collect the most specific physical unit available. Unit definitions are in Appendix I — Description of Units.

• kg
• tonne
• Unit
• £ Spend
• $ Spend

Which emission scope it falls under

Materials activity data typically maps to Scope 3 Category 1 under the GHG Protocol. Confirm organisational boundary and ownership before reporting.

Sub-types available in the platform

All 3 sub-types available in the platform.

• Construction materials
• Raw materials
• Average materials (spend)

Common questions

When should I use Materials instead of Metal, Plastic or another specific category?

Use Materials only when you genuinely can't identify a more specific material type, or when a purchase mixes several materials that aren't itemised separately. If your supplier can break a delivery down by metal, plastic or timber content, use those categories instead.

Does this cover construction materials for a building project?

Yes — general construction materials that aren't specifically metal, mineral, plastic or timber-based sit here, alongside mixed material deliveries typical of larger building projects.

We only have a total spend figure from our finance system for 'materials' — is that good enough?

It's a valid starting point using the average materials (spend) option, but it sits lower in the data hierarchy than a weight-based figure, so treat it as a baseline to improve on rather than a final answer.

How do I avoid double counting between Materials and Packaging?

Materials covers inputs to a product or a construction project; Packaging covers anything bought specifically to wrap, contain or ship a product. If a purchase serves both purposes, allocate it to whichever function it primarily serves.

Should raw materials that get processed on-site before use be tracked here, or after processing?

Track the raw material as purchased — this category captures the embodied emissions of the material itself, not the energy your organisation later spends processing it, which would be tracked separately as fuel or electricity use.