FRAMEWORK FOR CARBON NEUTRAL BUILDINGS AND SITES – AUGUST 2020
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Figure 5: Accounting of greenhouse gas emissions for the accounting scope 'Construction' (modules according to EN 15978)
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Raw material supply, Transport, Manufacturing (A1 - A3)
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Product stage
Production, transport, construction, use scenario, maintenance and waste management and landfill and recycling potential of the construction
Use stage
13 All foundations for life cycle assessment are described in the ecological accounting criteria (ENV1.1) in the DGNB criteria catalogue for ‘New Construction’, ‘Existing Buildings and Renovation’ and ‘Districts’. These can be requested from the website www.dgnb-system.de/en .
Waste processing (C3), Disposal (C4), Recycling potentials (D)
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Site
biomass or re-materialisation of greenhouse gas emissions at or outside the site) may not be taken into consideration because there is currently no consensus for the scientific basis of the determination and this process is not compliant wit the specifications of EN 15978. Deviating from these defined construction accounting scopes, further emission sources which are determined in the frame of the life cycle assessment, may not be taken into consideration in the overall account. If the accounting scope ‘Construction’ is selected, for a new build, all construction components are to be included in the account and for a renovation, only the newly introduced components are to be included with the help of a life cycle assessment calculation. The method for the life cycle assessment of buildings is to be used in order to determine the greenhouse gas emissions from the construction of new constructions, as they are defined in the country specific DGNB version or in the DGNB System Version 2020 International 'for new constructions'. Here, both the simplified and detailed methods are permitted.13
Use (B1), Replacement (B4) and Refurbishment (B5)
End of life / Recycling potentials
If the CO2 accounting is determined for the accounting scope ‘Construction’, the following rules apply for determining the ‘Initial absolute greenhouse gas emissions for the construction’: ■ Existing buildings are entered into the account with a construction value of 0 kg CO2. The accounting regulations of the DGNB life cycle assessment calculation apply for existing buildings. ■ For new constructions and new existing buildings (maximum building age = three years), the greenhouse gas emissions for all components of the life-cycle of the building as defined above are to be included in the account. If there is no life cycle assessment calculation, the reference value of the DGNB for the greenhouse gas potential of the construction can be used for the simplified determination of the construction. A country specific reference value or (if not applicable) the reference value of the 'DGNB System Version 2020 International' can be used, e.g. in Germany for most building uses the reference value of 9.4 kg CO2e/m²a at a reference study period of 50 years.14 14 The precise values for many of the different types of use is to be taken from the criterion ENV1.1. 'Building life cycle assessment' in the DGNB System for New Constructions, 2018 version or from the DGNB System Version 2020 International.