How do you calculate embodied carbon for timber?

Embodied carbon is calculated using the EN 15978 life cycle assessment framework, which divides the building life cycle into modules: A1–A3 (product manufacture), A4 (transport to site), A5 (construction), B1–B5 (in-use maintenance and replacement), C1–C4 (end of life), and D (benefits beyond the system boundary). For each module, multiply the quantity of timber (kg or m³) by the relevant carbon factor from an Environmental Product Declaration (EPD).

Embodied carbon is calculated using the EN 15978 life cycle assessment framework, which divides the building life cycle into modules: A1–A3 (product manufacture), A4 (transport to site), A5 (construction), B1–B5 (in-use maintenance and replacement), C1–C4 (end of life), and D (benefits beyond the system boundary). For each module, multiply the quantity of timber (kg or m³) by the relevant carbon factor from an Environmental Product Declaration (EPD). Sum all modules for the whole-life carbon figure.

Why this matters

This question relates to Embodied Carbon in Timber Construction: Calculation Methods, which covers the broader topic in detail. Understanding this specific aspect helps architects, builders, and timber dealers make informed specification decisions.

For full context and additional technical detail, see our comprehensive guide:

→ Embodied Carbon in Timber Construction: Calculation Methods

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About this answer

This answer is part of the PuurModulair Knowledge Base — comprehensive timber specification guidance for architects, builders, and dealers across the UK, EU, and Scandinavia.