This explainer is based directly on EN15804+A2 standards, which can be used as a reference even when following some other standards, like the NMD. The end-of-life stage of a (construction) product starts when it is replaced, dismantled, or deconstructed from the building or construction works and does not provide any further functionality. All output from dismantling, deconstruction, demolition, maintenance, repair, replacement, refurbishing, leaving the building is first considered to be waste, entering the end of life phase.
This article covers:
What is considered waste in LCA
modules C1-4 of EN15804+A2
Module D
This output is no longer considered waste when it meets all of the following criteria:
the recovered material is commonly used for specific purposes after collection
a market or demand, with positive economic value, exists for the recovered material
the material fulfils the technical requirements for the specific purposes and meets existing legistlation and standards applicable
the use of the recovered material will not lead to adverse environmental or human health impacts.
Modeling Tip: If your material meets all four criteria immediately upon deconstruction, it bypasses further waste processing in Module C3 and moves directly toward Module D. If it does not meet these criteria, it must be modeled through the C1–C4 waste modules as detailed below.
C1
Deconstruction & Demolition
All impacts associated with the dismantling or demolition of the product from the building, including initial on-site sorting of the materials, is included in module C1.
What to include: Energy consumption of demolition equipment (e.g., diesel for excavators, electricity for cranes or handheld power tools) and initial on-site sorting/sorting of materials.
How to model: If specific demolition data is unavailable, use standard industry averages or proxy datasets for mechanical deconstruction based on material mass.
C2
Transport
This transport represents the transportation of the discarded product as part of waste processing, to the gate of the recycling site and/or the final waste disposal plant.
What to include: Transport by truck, rail, or barge to the gate of a recycling yard, sorting facility, incineration plant, or landfill site.
How to model: Apply standard scenarios (e.g., national default transport distances) if the exact location of the waste processing facility is unknown.
C3
Waste Processing
This is where the impacts from the actual processing and separation of waste into its various streams is attributed. These streams can be a combination of landfill, recycling, and incineration.
If any product materials contain biogenic carbon, the release of this biogenic carbon back into the atmosphere is accounted for in this module.
Materials sent for waste-to-energy (incineration) are modeled here. Crucially, any energy recovery process operating below 60% efficiency (known as the R1 formula threshold) cannot be credited as energy recovery; its potential benefits are ignored, and it is treated purely as disposal.
C4
Disposal
Module C4 handles the final destination for materials that cannot be recycled, reused, or efficiently recovered for energy.
What to include: Landfilling of inert or organic waste, as well as incineration without energy recovery (or energy recovery below the 60% efficiency threshold).
Long-term Emissions: For landfills, this includes modeling long-term environmental emissions, such as methane generation from decomposing organic waste or heavy metal leaching into groundwater over time.
Looking Beyond: The Relationship with Module D
While Modules C1–C4 capture the impacts of getting rid of a product, Module D captures the net environmental benefits or loads that happen after the material passes the End-of-Waste state.
Whenever a material is successfully recycled or incinerated with high efficiency (>60%), it substitutes the need for primary virgin materials or fossil grid energy in the next product lifecycle. Documenting these net benefits in Module D provides a holistic view of your product's circular economy performance. Read more about module D here:
Feel like you're missing information? Check out the rest of our help center articles for more information on EPD modules and EN15804+A2