> ## Documentation Index
> Fetch the complete documentation index at: https://docs.realtimelca.com/llms.txt
> Use this file to discover all available pages before exploring further.

# EN 15804+A2

> The European Product Category Rules for construction-product Environmental Product Declarations (EPDs).

An **Environmental Product Declaration (EPD)** is a third-party verified document that reports the environmental impacts of a construction product over its life cycle, expressed per a declared unit (such as 1 kg or 1 m²). *EN 15804+A2:2019* — *Sustainability of construction works — Environmental product declarations — Core rules for the product category of construction products* — defines the rules every EN-compliant EPD must follow. Real-Time LCA's material library is structured around EN 15804+A2 so that EPD data flows cleanly into [EN 15978](/methodology-and-compliance/en-15978) whole-building calculations.

## Datasources

Real-Time LCA reads EPD data from multiple programme operators and generic-data sources. The currently supported datasources include:

* **[EPD Danmark](https://www.epddanmark.dk)**
* **[EPD Norge](https://www.epd-norge.no)**
* **[The International EPD System](https://www.environdec.com)** (Environdec)
* **[IBU](https://ibu-epd.com)** (Institut Bauen und Umwelt, Germany)
* **[OEKOBAUDAT](https://www.oekobaudat.de)** (German federal generic-data repository)
* **[Ecoplatform](https://www.ecoplatform.org)** (the EN 15804 aggregator)
* **Generic data** maintained inside Real-Time LCA
* **Tenant-private EPDs** uploaded by your organisation

See [Browse materials](/user-guide/library/materials/browse-materials) for how to filter and select by datasource and [Create materials](/user-guide/library/materials/create-materials/verified-epds) for verified-EPD authoring.

## EN 15804+A1 vs +A2

EN 15804 was significantly revised in 2019 (+A2). The two revisions differ in:

* **Indicator set** — +A2 adds new indicators and refines several existing ones, including a split of *GWP-total* into *GWP-fossil*, *GWP-biogenic*, and *GWP-luluc*.
* **Characterisation factors** — +A2 aligns with the *EF 3.0* characterisation method published by the European Commission.
* **Module D rules** — +A2 sharpens what may be reported in module D.

Real-Time LCA reads both +A1 and +A2 EPDs. Where a calculation type demands +A2 indicators that an +A1 EPD does not declare, the +A1 EPD can still be used, but the missing indicators will not be populated. Users should check the module coverage in the material library and decide whether to swap to an +A2 EPD or document the gap in their reporting.

It is industry consensus that GWP-total values from +A1 EPDs can be directly compared with GWP-total values from +A2 EPDs. Other impact categories (ODP, EP, AP, POCP, ADP) use different characterisation factors in +A2 versus +A1 and should not be compared directly across the two revisions.

## Declared unit vs functional equivalent

Each EPD reports its environmental impacts per a **declared unit** — typically a mass (1 kg), area (1 m²), volume (1 m³), or piece. The whole-building result is reported per the project's **functional equivalent**: kg CO₂-eq per m² GFA per year for most calculation types.

Here is how Real-Time LCA bridges the two:

1. **A quantity is recorded** for each component in the Building Component Inventory — sourced from a 3D model, IFC file, Excel import, or manual input — and linked to an EPD.
2. **The platform converts units** if the recorded quantity unit differs from the EPD's declared unit (e.g. if the EPD is declared per kg, the platform uses the density on the EPD to convert m³ → kg automatically).
3. **Emissions are calculated** by multiplying the converted quantity by the EPD's per-declared-unit impacts for each lifecycle module in scope.
4. **Results are aggregated** by summing all component emissions and dividing by gross floor area (GFA) and the reference study period to produce the final kg CO₂-eq / m² GFA / year figure.

## Module coverage per EPD

EPDs vary in which lifecycle modules they declare:

* **Cradle-to-gate (A1–A3 only)** — covers product stage. Real-Time LCA will use country-default end-of-life scenarios (C3, C4) to fill the gap when the project's calculation type requires those modules.
* **Cradle-to-gate with options (A1–A3 + selected later modules)** — common for EPDs that include A4, A5, B4, C, or D.
* **Cradle-to-grave** — full A1–C4 coverage, often with module D.

The product detail view in the material library shows exactly which modules each EPD declares so you can audit a project's coverage before reporting.

## EPD validity

Every EPD has:

* **Registration number** — the EPD's unique identifier, which can be used to look up the source document directly on the programme operator's website.
* **Programme operator** — who published it.
* **Verification status** — verified, draft, or generic.
* **Issue date and expiry date** — typically a 5-year validity window.

These fields are stored per EPD and visible in the material library. Users are responsible for checking EPD validity before finalising a report — an expired EPD may no longer reflect current manufacturing practices or regulatory requirements. See [Data quality](/methodology-and-compliance/data-quality) for how EPD versioning interacts with reproducibility of past reports.

## Relationship to EN 15941

*EN 15941* defines requirements for data exchange and data quality between EPD programmes. Real-Time LCA's datasource layer is designed to align with EN 15941 so that data ingested from one programme is treated consistently with data from another. See [Data quality](/methodology-and-compliance/data-quality).