How the Dutch environmental performance system works

The Dutch Environmental Database (NMD) is the independent organisation managing the system for calculating the environmental performance of buildings and civil engineering works in the Netherlands. The system combines a uniform calculation methodology (the Assessment Method) with a database of validated environmental data for construction products. For buildings, the result is expressed as the MPG. For civil engineering and infrastructure, the MKI is used. Both are based on the same underlying system, managed by the NMD.

What is the NMD?

The NMD is an independent foundation. We manage the Assessment Method and the database of validated environmental declarations. Our role is system management: maintaining the Assessment Method, validating environmental data and making that data publicly accessible.

The system is used by architects, project developers, designers, LCA practitioners, software providers and policy makers across the Dutch construction sector. International manufacturers, LCA bureaus and software developers working with Dutch construction projects also interact with the NMD system.

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The NMD system follows three steps: from preparing an LCA, via the Dutch Environmental Database, to the final MPG or ECI score.

LCA practitioners submit life cycle assessments in accordance with the Environmental Performance Assessment Method for Construction Works. Before this data may enter the database, it is reviewed in accordance with the NMD Review Protocol. Depending on the origin and the review of the data, an environmental declaration falls into category 1, 2, 3 or 3a.

The Assessment Method

The Environmental Performance Assessment Method for Construction Works is the established calculation methodology for environmental performance calculations in the Netherlands, managed by the Dutch Environmental Database. It is based on the European standard EN 15804. The method is performance-based and does not prescribe specific materials or construction techniques, but enables the comparison of design choices on the basis of environmental impact. The method is decisive at two steps in the process: in preparing an LCA (Input) and in calculating the MPG or ECI (Output).

While reading, do you come across unfamiliar terms or abbreviations, such as MPG, ECI or EN 15804? For an explanation of all commonly used terms within the NMD system, please see our glossary.

View the glossary

1. From Life Cycle Assessment (LCA) to an environmental declaration

An LCA (life cycle assessment) maps the environmental impact of a construction product over its entire life cycle: from raw material extraction and production, through transport and processing in the construction work, to maintenance, demolition and waste processing. The insights from an LCA also help manufacturers to make their production process more sustainable and to optimise it.

The outcomes of the LCA form the basis for the environmental declaration that is registered in the NMD database.

Environmental impact categories

The environmental impact of a construction product is calculated across 19 separate impact categories, including climate change (GWP), depletion of resources, acidification and particulate matter emissions. The categories are prescribed by the European standard EN 15804+A2.

In the environmental performance calculation, the results across all 19 categories are weighted and combined into a single score: the MPG for buildings or the ECI for GWW works.

2. Environmental data in the Dutch Environmental Database and calculation tools

Calculation tools are validated software applications that use the environmental data from the Dutch Environmental Database and the Assessment Method to carry out environmental performance calculations for a specific building (B&U) or GWW project. Calculation tool owners ensure correct implementation of the Assessment Method in their software, so that users can rely on accurate calculations. Before a calculation tool may be used within the system, it is validated by the NMD.

The environmental data is divided into three categories:

Product- and brand-specific environmental declarations, typically submitted by manufacturers.
Verification: verified by an independent, qualified third party in accordance with the NMD Verification Protocol.
Transparency: environmental declaration is public; underlying environmental information has limited accessibility.

Non-brand-specific data representing groups of manufacturers, suppliers and/or sectors.
Verification: verified by an independent, qualified third party in accordance with the Verification Protocol, including a statement on representativeness (e.g. representative for the Dutch market or a group of producers).
Transparency: environmental declaration is public; underlying environmental information has limited accessibility.

Non-brand-specific data managed by Stichting Nationale Milieudatabase.
Verification: not verified in accordance with the Verification Protocol.
Transparency: environmental declarations and reference profiles are publicly available.

Non-brand-specific data managed by Stichting Nationale Milieudatabase. This includes data on infrastructure for external energy supply, energy carriers, and environmental declarations for fully reusable building elements and installations in new construction.

Verification: not verified in accordance with the Verification Protocol.
Transparency: environmental declarations and reference profiles are publicly available. The 30% surcharge factor does not apply.

An environmental declaration for your product in the NMD

Are you a manufacturer or producer of construction products? Then you can have the environmental data of your product registered in the NMD database. For this, you need an environmental declaration prepared by an LCA practitioner and reviewed by a recognised LCA reviewer. After review, the environmental declaration is published in the database and your product can be included in environmental performance calculations by architects, advisors and contractors.

Through the Filling the Gaps Compensation Scheme, the NMD offers support to manufacturers who do not yet have an environmental declaration but wish to obtain one.

3. MPG and ECI

For buildings, the environmental performance is expressed as MPG (environmental performance of buildings): the total environmental impact of all materials used, expressed per m² gross floor area per year. A lower MPG means a lower environmental impact.

The MPG is mandatory for new residential buildings and offices. As of 1 July 2026, the requirement will also apply to other utility buildings such as schools, shops and healthcare institutions.

For GWW projects such as roads, bridges and hydraulic works, the Environmental Cost Indicator (ECI) is used. The ECI expresses the total environmental impact of materials and processes in a project as a monetary amount in euros.

The ECI is increasingly applied in tenders by public clients such as Rijkswaterstaat, ProRail and municipalities. It is used to compare design variants and to set environmental requirements in tenders.