The environmental performance calculation is conducted according to the Environmental Performance Assessment Method for Construction Works, see the ‘Assessment method’ page. The Assessment Method applies to calculating the environmental performance of both buildings and civil engineering structures. The Assessment Method does not focus on the environmental performance of individual products but on the environmental performance of the building or civil engineering structure as a whole. The building or structure is the unit for which the performance is measured and in which the product is used to enable the building to fulfil its function. The design and the intended service life are therefore determining for the installed construction products and the building installations and the number of replacements of these during the building’s service life.
A summary of the environmental performance assessment
According to EN15804, the Assessment Method gives practical instructions for analysing environmental performance. The Assessment Method is based on the environment oriented Life Cycle Assessment, or LCA. An LCA considers all phases in a product’s life cycle. This particularly relates to the function a product must fulfil in a building. An LCA assesses a product’s life cycle phases, including production, construction and disposal. Read more about this on the environmental data page. A Life Cycle Assessment (LCA) results in an environmental profile. Until end 2020, this profile comprised 11 environmental impact categories in accordance with EN 15804, but as EN15804 was amended in 2019 and its methodology was synchronised with the LCA methodology from the PEF (Product Environmental Footprint), from 1 January 2021 and in line with EN15804+A2, the profile comprises 19 environmental impact categories (NL) . (See image below)
A single point score – the environmental performance – is determined based on a weighting of the various environmental impact categories. For civil engineering, this is the Environmental Cost Indicator (ECI) score expressed in Euro and for Civil and Utility Construction (C&U) this is the Energy Performance of Buildings (EPB) score expressed in Euro/m2/year. Expressing the environmental performance in a single point score enables comparison with other buildings’ environmental performance as well as improved communication of the environmental impact and the requirements that are set. The environmental performance of a structure can be assessed using calculation tools that are validated in advance by Stichting National Environmental Database. See Calculation tools.
Interpretations and design issues in calculating the environmental performance of buildings
The Environmental Performance Calculation Guide, July 2020 version contains several interpretations and design issues for calculating the energy performance of buildings. The guide largely follows the context of the threshold for environmental performance as stated in the Building Decree, which came into force on 1 January 2018.
Impact of a building’s design on environmental performance
The guide includes the impact of a building’s design on environmental performance based on research by W/E adviseurs (Utrecht). This research clarified the impact on environmental performance of building additional storeys, bay windows and extra facade surface area.
Overview of the scope of a construction calculation for the various use functions
The Assessment Method includes an overview of the scope of the construction calculations for the various use functions from the Building Decree. All products and process cards in the NMD are coded according to the use functions for which the products apply. The products marked with an ‘x’ indicate the scope of an Energy Performance of Buildings (EPB) calculation in line with the Building decree. The products marked with an ‘O’ indicate the scope of an Environmental Cost Indicator (ECI) or EPB calculation in a broader application (above and alongside statutory requirements).
Including additional provisions in the EPB calculation
The system demarcation for environmental performance extends to the plot boundary: in the Building Decree, external energy supply installations as well as sewerage connections form part of environmental performance. As illustration, see the 2012 Building Decree Information Sheet relating to sewerage and municipal water management tasks. The illustrations in the Information Sheet clarify how far the provisions extend within the plot boundary and must therefore be included in the building’s environmental performance calculation.
Including installations for external energy supply in the EPB calculation
Installations for external energy supply (such as the connections for gas, electricity and/or heat as well as energy infrastructure and central systems for generation/conversion) must be included in the environmental performance calculation. Such systems will need to be mentioned in the energy performance calculation and an equivalent in terms of material use will need to be included in the environmental performance calculation. The National Environment Database includes so-called default values for this, which are determined by entering the calculated building-related energy consumption in the calculation.
Reference buildings for environmental performance monitoring and impact studies
In cooperation with LBP Sight, W/E adviseurs conducted the ‘Materialisation reference buildings’ study for Stichting National Environmental Database, in which fully materialised reference buildings were recorded. This set of reference buildings was developed to conduct valid impact and monitoring studies, with a view to possible changes in the EPB. This set is public so that calculations can be verified and reproduced.