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Life-cycle assessment (LCA) breaks down a product’s environmental impacts across distinct stages, from upstream material production through end-of-life. Variable follows the EN 15804+A2 standard, which defines a comprehensive framework for these stages.
EN 15804 calls each A1-D stage an information module. We use life-cycle stage throughout Variable - the two terms mean the same thing.

Stage overview

EN 15804+A2 organizes the product life-cycle into four main phases:
Module D (benefits beyond the system boundary) is reported separately and does not count toward a product’s total footprint. It captures potential benefits - reuse, recycling, energy recovery - that happen outside your system boundary.

Detailed stage reference

What to include in each stage

These are non-exhaustive examples to get you started. Your product’s PCR (Product Category Rules) is authoritative - always follow it where it differs from the guidance below.

A1: Materials

The materials in your model. Each input is a quantity of a Material - whether unprocessed (ore, timber), processed (steel sheet, plastic pellets), or pre-formed (a steel pipe, a molded housing). The Dataset behind each Material covers its upstream production from cradle to the supplier’s gate, including mining or harvesting, refining, and any supplier processing. It does not include transport to your factory - that’s A2. Packaging can fall into different stages depending on what it is: packaging on incoming supplier materials commonly sits in A1, manufacturing or product packaging in A3, and distribution packaging in A4. When in doubt, default to A1 - but always follow your PCR, which is authoritative on where each kind of packaging belongs.

A2: Transport to manufacturing

  • All transport modes from suppliers to your factory
  • Consider supplier location and transport distances

A3: Manufacturing

  • Electricity and fuel consumption
  • Direct emissions from a process (e.g., welding, curing, calcination, clinkering)
  • On-site waste generation and treatment
  • Water consumption and wastewater treatment

A4-A5: Distribution and installation

  • Transport to distribution centers and final customers
  • Installation energy and consumables
  • Construction site waste
  • Temporary works and scaffolding

B stages: Use phase

  • Energy consumed during operation (B6) - typically the largest use-phase contribution
  • Maintenance schedules and replacement cycles

C stages: End of life

  • Demolition and dismantling energy
  • Transport to waste facilities
  • Recycling processes
  • Landfill or incineration

Bundling and unbundling nested models

When a line in your bill of materials points to another product you’ve modeled in Variable (a nested model), you can choose how its stages appear:
  • Bundled (the default) — the nested model contributes as a single line carrying its cradle to gate (A1-A3) total, wherever the line sits in your model.
  • Unbundled — the nested model’s own stages are broken out and laid out individually, so its detail flows into your product across the matching stages.
Unbundling is available for every stage group: cradle to gate (A1-A3), distribution (A4-A5), use (B1-B7), end of life (C1-C4), and optional benefits (D). For the multi-stage groups this is how you pull a separately-modeled phase — for example a child end-of-life model with its own C1-C4 lines — into a parent product with the stages kept intact. Optional benefits (D) is a single stage: bundled, it imports the source’s cradle to gate (A1-A3) total; unbundled, it imports the source’s own module D credit (its recycling or recovery benefit) into stage D. Open a line’s actions menu and use the Bundling options to switch between bundled and unbundled; each option shows what it imports. Switching changes how the nested model’s detail is grouped into your product’s stages; it doesn’t change what the nested model itself contains.

Examples by product type

Electronics (laptop)

Construction materials (steel beam)

Consumer goods (furniture)