How we measure.
How we verify it.
What data we use at Descarboniza, how we tell verified data from industry averages, which standards we follow and what we can't guarantee. No tricks.
The basic unit of information: the EPD.
An Environmental Product Declaration (EPD) is a document, verified by an independent third party, that quantifies the environmental impact of a product across its life cycle.
EPDs are drawn up to the EN 15804 standard and registered with accredited programme operators — GlobalEPD, the International EPD System, IBU, EPD Ireland or equivalents. That lets you compare products against each other using the same methodology.
They are the only source of verifiable impact that exists today at product level. That's why they sit at the heart of Descarboniza.
We show A1–A3. The most comparable stage, and the most widely published.
A product's full life cycle is divided into stages. The five defined by EN 15804:
Product
Raw material extraction, transport to the factory and manufacturing. It's the stage most often published in EPDs and the one we show on the listings.
Construction
Transport to site and installation. It depends on the specific project, not on the product.
Use
Maintenance, repairs, energy and water over the service life.
End of life
Demolition, transport, waste treatment and final disposal.
Benefits
Loads and benefits beyond the system boundary (recycling, energy recovery).
A1–A3 is what's known as cradle-to-gate — from the cradle to the factory gate. It's the stage with the best coverage in published EPDs, and the only one you can compare product to product without depending on the specific project. We'll introduce stages B and C at system level once coverage is good enough.
Not all data carries the same weight. And we say so.
Manufacturer data with a current EPD.
Drawn from an EPD for the specific product, written to EN 15804, verified by an independent third party and registered with a programme operator. Valid for 5 years. It's the figure that appears on the listing with the Verified seal.
Average from public databases.
When a product has no EPD of its own, we fill the gap with public industry databases (ÖKOBAUDAT, ecoinvent or KBOB where applicable). It's useful for not leaving gaps, but it is NOT comparable to verified data and is always shown labelled as Industry average.
In the comparator, products with verified data carry the corresponding seal and are given visual priority. When a system mixes verified layers with industry-average layers, we say so explicitly.
The standards and frameworks we answer to.
Calculation rules for construction products.
Type III environmental declarations (EPDs).
Life Cycle Assessment — general framework.
Common European framework for sustainable buildings.
Spanish building code: energy demand and efficiency.
Technical screening criteria and DNSH.
What we can't guarantee.
- 01That a product with a good EPD is always the best option for the project. It depends on cost, performance, availability and context.
- 02That two EPDs are directly comparable if they follow different Product Category Rules (PCR). When there's doubt, we flag it.
- 03Real-world behaviour on site. The EPD describes the product, not the execution. Thermal bridges, airtightness and workmanship still belong to the project.
- 04Spanish industry data. Many public databases are European; when there's no local data, we say so.
- 05Endless validity. EPDs expire after 5 years. If one expires, we mark it as such.