Validation round for Environmental Performance of Renovation & Transformation started
This week, the validation round for the Assessment Method for Environmental Performance of Renovation & Transformation (MPG R&T) has started. The round runs until 1 December 2026. Calculation tools that participate and complete the validation successfully will be able to offer the method to users from that date onwards.
Purpose of the validation round
The validation round has been initiated to verify whether calculation tools have correctly and completely implemented the calculation rules and principles of the Assessment Method for Environmental Performance of Renovation & Transformation. The aim is to ensure uniform and consistent application of the method across validated calculation tools, so that users obtain the same results when using identical inputs.
Optional participation: what does this mean?
Participation in the validation round is optional. Not all validated calculation tools will implement the MPG R&T Assessment Method in their software. Whether a tool supports the method can be found on the Calculation Tools page at milieudatabase.nl, Calculation Tools page, where the scope of validation is specified per tool.
Two assessment methods for existing buildings
Existing buildings regularly undergo renovation, refurbishment or maintenance interventions to improve their technical condition, functionality or quality. This may be driven by deterioration, changing requirements, new performance standards or sustainability ambitions. Two Assessment Methods are available to make the environmental impact of such interventions transparent:
The Assessment Method for Environmental Performance of Renovation & Transformation (MPG R&T) applies to interventions at building level, such as major renovation or transformation. The result is expressed as an MPG value (euros per m2 gross floor area per year). The method aligns with the calculation framework used for new construction.
The Assessment Method for Environmental Performance of Maintenance (MPO) applies to interventions at element level, covering maintenance or refurbishment of individual building elements. The result is expressed as an MKI value (euros). A separate validation round for the MPO method will start in September 2026 and run until 1 March 2027.
Both methods use product data from the Dutch Environmental Database and allow users to make the environmental impact of interventions transparent, optimise a plan, and compare different plan variants. There is currently no statutory obligation to carry out an environmental performance calculation for existing buildings.
What is a validated calculation tool?
A validated calculation tool is private calculation software that has been validated by Stichting NMD for correct and uniform implementation of the Assessment Method(s) and the associated environmental data from the Dutch Environmental Database. The status "validated" indicates that the tool has successfully completed the validation procedure and delivers reliable and reproducible environmental performance calculations. To retain this status, tool holders are validated twice a year.
For more information on the Assessment Methods for existing buildings and ongoing developments, visit the Developments in environmental performance of existing buildings page.