Circularity Indices

Learn more about the DGNB Quality Standard for Circularity Indices for Buildings, as well as the DGNB Circularity Index

Europe is to become the world’s first climate-neutral continent based on a circular economy. Like no other sector of industry, the approaches we adopt to constructing, modernising and operating buildings will determine how these goals are met. In 2022, it was this insight that motivated the DGNB to develop the DGNB Building Resource Passport and create transparency regarding the defined circular properties of construction activities and buildings.

To continuously improve how building circularity is assessed or compared, however, especially for the sake of higher-level decision-making processes, the DGNB believes in using circularity indices. These are indicators that condense the assessment or comparison of building circularity into metrics. Analysing individual sub-indicators, use cases and circularity classes simplifies decision-making during the planning of construction projects, particular within the context of the circular economy. Capturing and documenting data – and then calculating circularity indicators on this basis – enables industry stakeholders to make validated decisions and thus support the transformation to a circular economy.

There are currently a number of indices and calculation methods offered by the market, but at the same time, until now there has been no uniform definition of the requirements such an index should fulfil. What’s needed is a common fundamental language, not only to be able to conduct meaningful aggregated circularity assessments, but also to make comparable assessments of circularity scores. Accordingly, the DGNB has been working through the DGNB Committee for Life Cycle and Circular Building to develop a quality standard for circularity indices applied to buildings. Based on this, it has also now developed its own index.

Circularity indices combine technical parameters into individual key figures based on given metrics
This supports the fulfilment of overarching environmental goals with a bearing on the circular economy

Document|pdf|English|2 MB

DGNB quality standard for circularity indices for buildings

Publication: 03.05.2024

Basic understanding of quality and DGNB Circularity Index | Version 1.0

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Circularity indices and the determination of circularity quotas can be used in construction projects and for certification purposes. For example, for DGNB certification purposes the 2023 version of the DGNB System for the New Construction of Buildings contains the circular building criterion TEC1.6, the aim of which is to motivate people to use circularity indices. This makes explicit reference to the DGNB standard for circularity indices. In addition, using circularity indices and determining circularity quotas can also feed into local or higher-level regulatory requirements.

By focusing on individual areas or sub-indicators on a building level, aggregated circularity assessments can also offer orientation. Circularity indices can thus also provide third-party stakeholders with concise insights into what has already been achieved. They can also be used as a management tool. A circularity assessment can be relevant for sustainable and resource-optimising project planning decisions, as well as any evidence required for different steering instruments, e.g. project contributions to the circular economy.

A circularity index that combines different approaches can be used in a project to...

Highlight circularity and environmental factors and offer structure
Provide a basis for planning renovations, new buildings and demolition projects while also considering resources and the environment
Define the sustainability properties of building materials, products and components
Provide a basis for new steering and subsidy instruments
Make it easier to assess and provide meaningful information on establishing 'urban mines'
Document construction and demolition waste – and help reduce waste
Provide structure for digital property documentation, for both new and existing buildings
Provide valuable and suitable documented evidence for disclosure regulations
Document materials put to secondary use
Demonstrate the suitability of structural building elements for subsequent use

Indices can be used by anyone involved in the construction process. However, they are primarily used by building planners involved in the digital planning and documentation of buildings, aspects of sustainability encountered in construction planning, or both.

Requirements affecting circularity indices

In accordance with the DGNB quality standard, circularity indices should contribute in the following ways:

They should contribute to pre-use (implemented) circularity at the current time
They should contribute to post-use (potential) circularity in the future

Depending on the context and application (long-lasting vs. short-lived, new construction vs. existing buildings vs. renovations), priorities should be set for current and future contributions to the circular economy on a differentiated basis:

Short-lived buildings: current circularity ≤ future circularity

Long-lasting buildings: current circularity ≥ future circularity

Objectivity of the assessment method, with explanations of conducted assessments
Complete coverage of KG 300 (DIN 276 cost group for building construction), declaring missing areas
Coverage of KG 400 (DIN 276 cost group for technical building services) according to relevance by mass, declaring missing areas
Transparent and freely available descriptions of methods applied

Declaration of quantitative sub-indicators for making improvements in targeted areas, covering material origin, construction and demolition waste, pollutant load and material compatibility, detachability, material separability and material recycling (potential)
Timing preferences per use case to take into account current requirements to make changes
Extensions possible – e.g. based on the results of life cycle assessments, assuming this can be declared separately

The sub-indicators for pollutant load and material compatibility can also be included in the sub-indicator for material recycling by assessing recyclability based on impurities/interfering substances
The sub-indicators for detachability and material separability can also be evaluated together as a single indicator

Note: after showing which methods were used and explaining these methods, as well as matching their conformity with the defined quality standard, it is also possible to determine circularity indices that deal meaningfully and in quantitative terms with all topics covered by the sub-indicators, although such indices do not reflect topics separately and do not use the same circularity classes (CC).

Basic method for calculating circularity indices

The following method has been developed as a basis for calculating circularity indices:

Overall contribution: CI = Circularity index of pre-use and post-use circularity

Comprising two contributions:

Current contribution: CI_(C)	= (Partial) circularity index of pre-use circularity
	The current contribution is calculated by taking the product of the following sub-indicators and corresponding application-specific weighting factors. Sub-indicators: material origin, construction and demolition waste, pollutant load

Future contribution: CI_(F)	= (Partial) circularity index of post-use circularity
	The future contribution is calculated by taking the product of the following sub-indicators and corresponding application-specific weighting factors. Sub-indicators: material compatibility, detachability, material separability, material recycling (potential)

as well as tolerances when applying the quality standard for

The partial circularity indices CI_(C) and CI_(F) = ± 15 % (by contribution)
The weighting of sub-indicators W_SI = ± 5 % (by sub-indicator)
The assessment factors of the CC by sub-indicator f_cc = ± 0.15 (by circularity class)

This calculation method makes allowances for deficits relating to specific areas of use, also making it possible to focus on activities that support the current and future circular economy. The modular approach this method is based on allows individual values to be adapted, thus making it easy to respond to future developments. This method is adaptable because it offers the possibility either to use a holistic circularity index (to assess overall contributions to the circular economy, i.e. pre-use and post-use circularity), or to conduct a separate assessment based on two partial circularity indices (pre-use or post-use circularity) by looking separately at current and future contributions to the circular economy.

Our 2024 publication, DGNB Quality Standard for Circularity Indices for Buildings offers detailed information on calculations as well as an example calculation based on the use case of new buildings.

Overview of sub-indicators – circularity classes and assessment factors

The six sub-indicators that were analysed were based on specialist research. As such, they reflect the topics that are relevant when it comes to assessing the overall contribution of buildings to the circular economy. They can be used for guidance purposes, applied separately to project planning, or used to make specific optimisations, although they do not constitute a circularity index in themselves.

Showing the origin of materials should make it easier to use fewer primary or non-renewable resources and thus increase the proportion of secondary material in a building. Mass-based quotas are therefore categorised according to the content of secondary and primary raw materials. This sub-indicator is given emphasis in the weighting.

Classified assessment factors and circularity classes of the material origin (C) sub-indicator (mass in per cent)
Circularity class		Description	Assessment factor f_CC(C)	Tolerance
secondary	Reuse	(Reuse), existing building stock = 100 %	1.00	± 0.15
	Repurposed	(Remanufacture/repurpose)	1.00	± 0.15
	Recycled, in closed loops	(Recycling) = post-consumer recycled content, uniform quality, closed-loop recycling	0.75	± 0.15
	Recycled, in open loops	(Recycling) = post-consumer recycled content, reduced quality, open-loop recycling	0.50	± 0.15
primary	Primary raw material, renewable	(Renewable) certified (high-quality, with reforestation) or comparable (e.g. rapidly renewable) e.g. according to DGNB criterion ENV1.3 from the DGNB System for New Construction of Buildings. Version 2023	0.75	± 0.15
	Primary raw material, renewable	(Renewable)	0.50	± 0.15
	Circularity classes above 0.50 should be aimed for to achieve a positive contribution to the circular economy
	Primary raw material, non-renewable	(Not renewable)	0.00	± 0.15

Note: if it is not possible to categorise waste separately as reused, repurposed or recycled, the category relating to the lower quality of material must be used.

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

Waste generated by demolition and construction work has been included in this quality standard because it can potentially play an important role in resource conservation. In Germany, waste stream declarations are mandatory for all construction projects under current regulations. This issue is also an important aspect of the EU taxonomy, which, under the Do No Significant Harm criterion, stipulates that evidence must always be provided of the degree of reuse or recycling of non-hazardous construction and demolition waste.

Classified assessment factors and circularity classes of the construction/demolition waste sub-indicator (C) (mass in per cent)
Circularity class	Description	Classification: draft of circularity index (BBSR)			Assessment factor f_CC(C)*		Tolerance
Circularity class	Description	EoL class	Potential	Index	Construction waste	Demolition waste	Tolerance
Reuse	Including preparation for reuse	A	WV	140	1.00	1.00	± 0.15
High-quality closed-loop recycling	High quality, including upgrading, closed-loop recycling	B	CL	100	0.80	0.80	± 0.15
Material recycling	Recycling without effort, closed-loop recycling with effort	C	RC*/CL (with effort)	80	0.70	0.70	± 0.15
	Recycling with processing effort, open-loop recycling	D	RC (with effort)	60	0.60	0.60	± 0.15
	Circularity classes above 0.50 should be aimed for to achieve a positive contribution to the circular economy
	Recycling with inferior quality, other material recycling	E	SV	20	0.40	0.40	± 0.15
Energy recovery	Renewable/biogenically certified and demonstrably low in pollutants	E	EV+	20	0.40	0.40	± 0.15
	Non-renewable/biogenic, renewable/not biogenically certified	F	EV-	-20	0.20	0.20	± 0.15
	Energy disposal	G	EB	-60	0.00	0.00	± 0.15
Backfilling	Non-hazardous material	F	Dep+	-20	0.20	0.20	± 0.15
Disposal	Non-hazardous waste (DK 0-II), incl. landfilling of inert waste	F	Dep+	-20	0.20	0.20	± 0.15
Disposal	Hazardous waste (DK III-IV), disposal after processing	G	Dep-	-60	0.00	0.00	± 0.15

*Assessment based on the ratio of classes according to the draft of BBSR circularity potential (November 2023)

Construction and demolition waste are looked at within the context of building measures. This means that only non-hazardous construction and demolition waste generated as part of a documented building project is considered. Construction and demolition waste declared as hazardous should be classified under ‘disposal as hazardous waste’ and must be dealt with in accordance with statutory regulations.

With existing buildings, or if there is no recovery, it is not necessary to consider construction and demolition waste, as these fall purely under existing building assessments.

With the preservation of existing buildings, it is not necessary to consider demolition waste if there is no recovery, as this falls under the assessment of new building measures.

With recovery: construction and demolition waste
Without recovery: construction waste

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

The issue of pollution must not be overlooked due to its impact on subsequent use. The assessment is based on a qualitative classification of the entire building or the total building stock mass and not in mass-based quotas.

Classified evaluation factors and circularity classes of the sub-indicator pollution (H)
Circularity class	Description	Assessment factor f_CC(C)	Tolerance
Objective	Analysis conducted, no pollutants present	1.00	± 0.15
Optimised	Analysis conducted, pollutant remediation carried out (incl. hazardous/interfering substances), pollutant register of remaining harmful substances documented	1.00	± 0.15
High standard	Analysis conducted, pollutant remediation carried out, pollutant register of remaining harmful substances documented	0.75	± 0.15
Standard	Analysis conducted, pollutant register of harmful substances exists	0.50	± 0.15
Circularity classes above 0.50 should be aimed for to achieve a positive contribution to the circular economy.
Critical	No assessment, doubts exist (e.g. based on year of construction)	0.00	± 0.15
Assessment is not possible	No analysis, doubts do not exist	0.00	± 0.15

For example, classification of the building within the overall context is based on the DGNB criterion for new construction (ENV1.2: Local environment impact) because there is currently no standard or regulatory method of comprehensive classification. It is also possible to conduct assessments based on different classification methods, e.g. on a material level according to DGNB criterion TEC1.6, Indicator 3.2.2, which is also from the DGNB System for New Construction of Buildings, Version 2023, or other methods provided by recognised certification systems, as also specified.

In all instances it is an important requirement that all hazardous substances/pollutants are reported in a hazardous substances/pollutants register as part of an analysis of the building stock. The status and result of assessments can be shown according to the above qualitative classification system.

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

Material compatibility should not be overlooked due to the impact this has on subsequent use. Not only are hazardous and harmful substances important for health reasons, but potentially harmful or interfering substances are also important when it comes to the future recycling of material resources or transferring materials to downstream processes after the end of the useful life of resources or buildings. Accordingly, newly introduced materials are categorised according to their circularity properties in keeping with the classification system.

Classified assessment factors and circularity classes of the material compatibility sub-indicator (C) (mass in per cent)
Circularity class	Description	BBSR interfering substance class*	DGNB criterion: ENV1.2 of the DGNB System for New Construction of Buildings, Version 2023***	Assessment factor f_CC(C)	Tolerance
Objective	Free of pollutants	S1, S2		1.00
Optimised	Largely free of harmful substances, with material testing, not hazardous to health, does not inhibit post-use circularity**	S1, S2	QS4	1.00	± 0.15
High standard	With material testing, not hazardous to health, does not inhibit post-use circularity**	S1, S2	QS3	0.75	± 0.15
Standard	Not hazardous to health, does not inhibit post-use circularity**	S1, S2	QS1-2	0.50	± 0.15
Circularity classes above 0.50 should be aimed for to achieve a positive contribution to the circular economy.
Critical	Inhibits pre-use circularity	S3, S4		0.00	± 0.15
Assessment not possible	Insufficient information available			0.00	± 0.15

^{1 for secondary material
*Assignment to impurity classes of material compatibility according to draft BBSR Circularity Index (Nov. 2023)
** See relevant parts of EoL according to the criteria matrix in criterion ENV1.2 of the DGNB System for New Construction of Buildings, version 2023, see Figure 6
***Assigned system for determining quality levels according to criterion ENV1.2 of the DGNB System for New Construction of Buildings, version 2023}

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

This is the potential to remove in its entirety a component, element or constituent of a material installed in a building (also referred to as ease of disassembly or recoverability). Components, elements or constituents of materials that are designed such that reversible connections can be used to install and dismantle them again, without damage, also support detachability. Being able to disassemble materials properly is a fundamental aspect of subsequent recyclability. Assessing the ability to recover building materials is seen as an intrinsic element of future contributions to the circular economy, because capturing the effort required to recover a building provides an important indication not only of the economic viability of selective recovery, but also of the share of resources that can be returned to material cycles. In addition, immediately reusing entire components or building materials can be demonstrated and made easier by assessing detachability.

Classified assessment factors and circularity classes of the detachability sub-indicator (F) (mass in per cent)
Circularity class	Description			Assessment factor f_CC(C)	Tolerance
Circularity class	Connection	Recovery effort	Damage type	Assessment factor f_CC(C)	Tolerance
Optimised	Loose/click connection	Very little effort	Removable without damage	1.00	± 0.15
Improved	Inserted/plugged /screwed in	Little effort	Removable without damage	0.75	± 0.15
Standard	Fixed in place/ permanently installed	Medium effort	Mainly detachable without damage	0.50	± 0.15
Circularity classes above 0.50 should be aimed for to achieve a positive contribution to the circular economy
Limited	Fixed in place/permanently installed	Major effort	Repairable damage	0.25	± 0.15
Problematic	Fixed in place/permanently installed	Extremely complex	Irreparable damage	0.00	± 0.15
Assessment not possible	Or cannot be dismantled			0.00	± 0.15

^{* Use of circular products on a component level: assigned classification according to criterion TEC1.6, Indicator 3.2.2 of the DGNB System for New Construction of Buildings, Version 2023
** With evidence that the material can be disassembled without damage
*** Applies to building materials/systems consisting of several components/materials}

Note: buildings span different hierarchies with individual life cycles, which should be taken into account during planning. In terms of circularity, detachability is particularly relevant for the structural levels whose components/products/materials have a shorter service life or more frequent replacement cycles.

To classify detachability with buildings, the nature of connections, recovery effort and resulting damage are assessed. To determine which assessments factors to use, previously used methods were compared and discussed, looking at relevance and applicability, and in some cases average values were calculated.

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

Material separability refers to the ability to separate materials/components/elements or their individual constituents and thus keep material flows separate based on individual origins.

Material separability is important partly because of its relevance to the economic viability of selective recovery, but also because of the proportion of resources that can be returned to the material cycle. Assessing the single-origin recovery of building materials has been added to the quality standard as a separate sub-indicator because it requires different assessment compared to the potential to disassemble building components/materials. In addition, this factor is increasingly being applied at a material level.

Classified assessment factors and circularity classes for the material separability sub-indicator (F) (mass in per cent)
Circularity class	Description			Assessment factor f_CC(C)	Tolerance
Circularity class	Process	Effort	Effect on post-use circularity	Assessment factor f_CC(C)	Tolerance
Optimised	Without tools	Easily accessible	Without attachments, mono-material, completely recyclable/full recovery	1.00	± 0.15
Improved	With tools		Completely recyclable/recoverable	0.75	± 0.15
Standard	With tools/ chemicals		Almost completely recyclable/recoverable	0.50	± 0.15
Circularity classes above 0.50 should be aimed for to achieve a positive contribution to the circular economy
Limited		Complex	Not fully recyclable/recoverable	0.25	± 0.15
Problematic		Extremely complex	Not fully recyclable/recoverable	0.00	± 0.15
Assessment not possible	Or cannot be separated by single origin			0.00	± 0.15

To classify the potential to separate materials used in buildings, an assessment is made of single-origin processes and impacts on pre-use circularity. To determine which assessment factors to use, previously used methods were compared and discussed, looking at relevance and applicability, and in some cases average values were calculated

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

Material recovery describes the potential to follow typical paths of subsequent use for building materials/products/components according to the current status of technology. This is important when it comes to assessing the future circularity of resources used.

Classified assessment factors and circularity classes of the material recycling sub-indicator (F) (mass in percent)
Circularity class	Description	Classification: draft circularity index (BBSR)			Assessment factor f_CC(C)**	Tolerance
Circularity class	Description	EoL-Class	Potential	Index	Assessment factor f_CC(C)**	Tolerance
Reuse	Including preparation for reuse	A	WV	140	1.00	± 0.15
High-quality closed-loop recycling	High-quality, including upgrading, closed-loop recycling	B	CL	100	0.80	± 0.15
Material recycling	Recycling without effort, closed-loop recycling with effort	C	RC/CL (with effort)	80	0.70	± 0.15
	Recycling with processing effort, open-loop recycling	D	RC (with effort)	60	0.60	± 0.15
	Circularity classes above 0.50 should be aimed for to achieve a positive contribution to the circular economy
	Recycling with inferior quality, other material recycling	E	SV	20	0.40	± 0.15
Energy recovery	Renewable/biogenically certified and demonstrably low in pollutants	E	EV+	20	0.40	± 0.15
	Non-renewable/biogenic, renewable/not biogenically certified	F	EV-	-20	0.20	± 0.15
	Energy disposal	G	EB	-60	0.00	± 0.15
Backfilling	Non-hazardous material	F	Dep+	-20	0.20	± 0.15
Disposal in landfill	Non-hazardous waste (LC 0-II), incl. landfilling of inert waste	F	Dep+	-20	0.20	± 0.15
Disposal	Hazardous waste (LC III-IV), disposal after processing	G	Dep-	-60	0.00	± 0.15

^{* Assessment based on ratio of classes according to the draft of BBSR circularity potential (November 2023)}

To determine future material recovery potential, an assumption can be made regarding the typical path of subsequent use according to the current status of technology in keeping with the applicable life cycle assessment guidelines for the EoL phase. Other assessment levels can also be considered for this, such as those applied to building materials or components, and this may make particular sense for high-level circularity classes.

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

Data basis used to assess circularity

A building resource passport (BRP) can serve as a basic source of information for calculating circularity indices in accordance with the DGNB Quality Standard. As an instrument that is based on actual application and the market, a BRP provides transparent documentation and aggregated data on a building level, and this also allows consolidated circularity assessments to be determined.

To determine the data to be used for a BRP or a circularity assessment, a calculation of costs based on masses can be used, supplemented with circularity attributes. This analysis can be formed as a bill of quantities or a building component catalogue, with the underlying structure based on cost categories defined under DIN 276, or using building information modelling according to the same attribute logic. Quantities used to calculate the cost of building projects are usually estimated during the design phase (phase 3 of the German HOAI fee schedule for architects and engineers).

To make it easier to pull information together, databases and software services can be used, which either draw on their own databases or can be linked. It is important from the outset to consider requirements for the data points to be collected and for the data modelling.

Possible areas of application include building installations and buildings in accordance with Sections 1 and 2 of the German standard building regulation MBO. It is recommended that the scope of assessments extends to relevant technical installations (based on mass).

The DGNB Circularity Index

The DGNB Circularity Index was derived from the DGNB Quality Standard as a standalone product and it can be seen as a potential tool for assessing the circularity of buildings. The calculations it is based on correspond to the same fundamental method, although the weightings of sub-indicators contained in the quality standard are used without tolerances in the DGNB Circularity Index.

Circularity indices in Germany

The DGNB is aware of the following methods used for circularity assessments in Germany and other German-speaking countries (as of December 2023, alphabetical order). These were also considered while conducting developmental research on the DGNB Quality Standard for Circularity Indices for Buildings:

Relevant circularity assessment methods according to levels, life cycle phases and indicators (based on: Circularity Score (L. Hildebrand et al. (2023)), dissertation (unpublished) by S. Theißen)
Method	Circularity Score (CS)	Concular Circularity Performance Index (CPX)	DGNB Circularity Index (DGNB CI)	EPEA Circularity Passport® Buildings (CP)	IBO Disposal Indicator (DI)	Madaster Circularity Indicator** (MCI)	Urban Mining Index (UMI)	Recycling-Graph	Draft Circularity index for the assessment of circularity (German government)
Scope	Circularity Score (CS)	Concular Circularity Performance Index (CPX)	DGNB Circularity Index (DGNB CI)	EPEA Circularity Passport® Buildings (CP)	IBO Disposal Indicator (DI)	Madaster Circularity Indicator** (MCI)	Urban Mining Index (UMI)	Recycling-Graph
Levels	Building Component Material	Building Component Material	Building Component Material	Building Component Material	(Building) Component	Building (Component) Material	Building Component Material	Building Material	(Building) (Component) (Material)
Phases	Future contribution (post-use) = subsequent use phase with use phase	Current contribution (pre-use) = construction phase Future contribution (post-use) = subsequent use phase	Current contribution (pre-use) = construction phase Future contribution (post-use) = subsequent use phase (with use phase)	Current contribution (pre-use) = construction phase Future contribution (post-use) = subsequent use phase with use phase	Future contribution (post-use) = subsequent use phase	Current contribution (pre-use) = construction phase Future contribution (post-use) = subsequent use phase with use phase	Current contribution (pre-use) = construction phase Future contribution (post-use) = subsequent use phase with use phase	Future contribution (post-use) = subsequent use phase	Future contribution (post-use) = subsequent use phase
Sub-indicators: implemented circularity (current/pre-use)		Material origin	Material origin Construction/demolition waste Pollutant load	Material origin (Carbon footprint) Pollutant load		Material origin (Carbon footprint)	Material origin (Carbon footprint) Pollutant load
Sub-indicators: circularity potential (future/post-use)	(Re-usability) Detachability Material recycling	(Re-usability) Detachability Material separability Material recycling	Material compatibility Detachability Material separability Material recycling	Detachability Material separability Material recycling	Material recycling	Detachability Material recycling	Material compatibility Detachability* Material separability* Material recycling*	Detachability Material recycling	(Material compatibility) (Detachability) (Material recycling)

^{* According to material-specific EoL scenario for selective recovery or standard demolition, including assessment of the economic viability of recovery
** Based on the Material Circularity Indicator (MCI) of the Ellen MacArthur Foundation
( ) = brackets indicate criteria that cannot be clearly or completely compared or those not taken into consideration}

The table is an attempt to categorise the different methods in terms of life cycle phases, levels of consideration and sub-indicators. The scope described illustrates the limitations of the methods as well as the focus on circularity and recyclability.

A circularity index is currently being developed at federal level (as of November 2023) to assess potential circularity as part of efforts to create a digital building resource passport. As the results and basis for these developments are only available in draft form and have not yet been finalised, the information on federal instruments in the table above should be treated with caution.

For further information, please refer to our publication, DGNB Quality Standard for Circularity Indices for Buildings.

Frequently asked questions

In addition to the DGNB Quality Standard for Circularity Indices for Buildings, a specific methodology has been developed for a circularity index in order to reflect the DGNB’s overarching sustainable building objectives. Using this quality standard allows evaluations to be conducted within defined tolerance ranges. This contrasts to the DGNB Circularity Index, which is not based on tolerances and uses fixed weightings of the sub-indicators or applies factors to the circularity classes. Assuming the guidelines of the quality standard are observed, circularity assessments can be used for buildings, within certain limitations, and are still comparable.

The combined and aggregated circularity scores offer information on how ‘circular’ a building is. We recommend achieving circularity classes of 0.50 or more, as these make a positive contribution to the circular economy. Assessments of achieved circularity rates – based on criterion TEC1.6, Indicator 3.2.1 of the DGNB System for New Construction of Buildings, Version 2023 – can serve as additional guidance for categorising the results. This process describes which circularity classes are attributed to making a positive contribution to the circular economy in the determination of mass-based quotas. Not only were these determined by analysing previous use, but also reference was made to the control instruments used on an EU level for sub-indicators material origin, construction and demolition waste, and material recycling (potential).

Facilitating the application and open exchange of knowledge regarding hands-on experience can (and should) make it possible to develop a standard language for the topics of resources and circularity in construction. Applying a standard and transparent methodology is also intended to engender credibility on an overarching level and allow comparisons to be made.

In the future, standardising application will make it possible to define comparable benchmarks for certification and management instruments.

The formal and content requirements described in the DGNB quality standard, which, among other things, require a transparent and freely accessible description of the methodology, are intended to make the underlying calculation methodology comprehensible to everyone.

The DGNB is not currently intending to conduct individual assessments on completed BRPs or the circularity indices of buildings, but we do conduct reviews according to the requirements laid down under criterion TEC1.6 during project certifications in accordance with the DGNB System for New Construction of Buildings, Version 2023. When using an aggregated circularity index, these requirements are checked qualitatively in accordance with the quality standard on the basis of evidence to be submitted.

Concerning DGNB certification, it is being evaluated whether a procedure should be developed and made available for recognising tools used to produce DGNB Building Resource Passports, also with a view to standardising the review of certified projects and results. This could also allow circularity assessments to be compared with the quality standard outlined on this website.

No, there are differences. Compared to an aggregated circularity assessment, circularity rates assessed using criterion TEC1.6 under Indicator 3.2.1 constitute simplified calculations. When determining the circularity rates, ‘high-quality’ classes (i.e. circularity classes that make a positive contribution to the circular economy), are totalled or included as 100 per cent. When calculating the DGNB Circularity Index, the circularity results of the sub-indicators are determined by additionally applying an assessment factor to the circularity classes.