• What is DGNB Certification?
• DGNB Certification Criteria
• The central role of LCA in DGNB certification
• The role of engineers in the DGNB approach and optimization through LCA
• How does Vizcab facilitate DGNB LCA?

Established in Germany in 2007, the DGNB certification has become, in less than twenty years, one of the most widely used frameworks in Europe for assessing the sustainability of new and existing buildings. With more than 7,700 registered projects across 32 countries and a dominant position on the German market 83% of newly certified tertiary buildings it now stands as a major standard for sustainable construction.

Its approach, based on the life cycle perspective, carbon footprint reduction, and multi-criteria assessment, makes it particularly well suited to current European requirements such as the EU Green Taxonomy, CSRD, and ESG reporting. In a market increasingly focused on transparency and measurable evidence, DGNB emerges as a strong benchmark for low-carbon construction.

What is DGNB Certification?

German origins, a holistic approach (environmental, economic, sociocultural, technical, process, and site aspects)

DGNB was established in Germany in 2007, at a time when the European Union was strengthening its climate ambitions: a 55% reduction in greenhouse gas emissions by 2030, carbon neutrality by 2050, the development of EN 15978 (building LCA) and EN 15804 (EPDs), and the growing importance of ESG policies. The German objective was clear: to create a framework capable of assessing the true sustainability of a building, beyond energy performance alone.

From the outset, DGNB adopted a holistic approach, structured around six categories of criteria: environmental, economic, sociocultural, technical, process, and site quality. Now standardized through its 2018, 2020, and 2023 versions, the system is based on a logic of overall performance, aligned with European standards and integrating embodied energy, carbon impact, quality of use, and sustainable planning. Today, more than 1,000 trained auditors worldwide¹ contribute to strengthening this framework.

This approach meets the expectations of a market seeking sustainable, transparent, and resilient buildings, capable of achieving low-carbon or even carbon-neutral construction objectives.

The importance of life cycle thinking and overall performance

The defining characteristic of DGNB lies in the central role given to life cycle assessment (LCA). Unlike other certification systems that treat LCA as a secondary indicator, DGNB makes it a core pillar of its evaluation framework: carbon impact, embodied energy, resource use, material durability, and life cycle costs are all integrated into a systemic vision that truly measures the building’s overall performance.

DGNB is directly based on European standards:

• EN 15978: building LCA methodology
• EN 15804: product data (EPDs / FDES)
• ISO 14040 / 14044: general LCA framework

LCA is a key lever for achieving Silver, Gold, or Platinum certification levels.

This life cycle–based perspective is particularly well suited to current needs: in high-performance new buildings, embodied carbon from materials now accounts for the majority of emissions, while the operational phase represents only a minor share, as a result of significant progress in energy efficiency. Life Cycle Assessment (LCA) therefore becomes essential.

Positioning compared to LEED, BREEAM, and HQE

Compared with other international standards such as LEED, BREEAM, and HQE, DGNB follows a distinct approach (read our article on international certifications to learn more).

Like LEED, BREEAM, and HQE, DGNB is a multi-criteria certification that integrates multiple dimensions of building performance. However, it places a stronger emphasis on a balanced and comprehensive assessment, applied consistently across the entire life cycle of the building.

Its rigorous requirements for life cycle assessment, transparent structure, and focus on actual performance align with a broader trend now shared by several certification schemes, notably reflected in the recent evolution of BREEAM v7.

DGNB has become the reference certification in Germany, primarily due to its strong national roots, and is gradually expanding to other European countries (Denmark, Switzerland, Spain, Croatia, and Luxembourg), driven in particular by stakeholders and investors already familiar with the framework.

Why is DGNB gaining importance? 

DGNB certification is gaining importance because it responds to the converging expectations of investors, real estate developers, and public authorities.

Institutional investors are among the main drivers of certification. With the EU Taxonomy, ESG reporting, and the CSRD, they are now required to demonstrate the non-financial performance of their assets. DGNB, aligned with EN 15978 (building LCA) and EN 15804 (environmental product declarations), provides a clear framework to demonstrate the actual sustainability of buildings³. It is one of the very few certification systems that systematically integrates life cycle thinking, carbon footprint, embodied energy, and life cycle costs over the building’s entire lifespan.

Developers rely on certification to enhance the value of their projects, reassure buyers, and respond to the growing demand for sustainable buildings and low-carbon development strategies. In Germany, DGNB accounts for 83% of newly certified tertiary buildings³, making it a true market standard. The certification strengthens transparency, perceived quality, and trust among both investors and end users.

Public authorities also play an increasing role in the adoption of DGNB. As part of their climate strategies (2030–2050), they seek buildings that are genuinely aligned with carbon neutrality objectives and based on measurable criteria. Several German cities now include DGNB requirements in their public procurement processes.

A notable example is the city of Berlin, which required DGNB certification for several buildings within the Berlin TXL – The Urban Tech Republic project (Campus West) in its official 2023 public tender⁵.

Link to the public tender:
👉 https://ausschreibungen-deutschland.de/2028206_Berlin_TXL_-_UTR_-_Beratung_und_Planung_DGNB-ZertifizierungReferenznummer_der_Bekanntmachung_2023_Berlin

Link to the DGNB project page:
👉 https://www.dgnb.de/en/certification/dgnb-certified-projects/project-details/berlin-txl-the-urban-tech-republic-campus-west

DGNB Certification Criteria

The six categories of criteria 

The DGNB certification system is built on a unique structure organized around six main categories of criteria. This framework reflects the holistic philosophy of DGNB, which aims to assess the overall sustainability of a building, rather than focusing on a single isolated aspect.

• Environmental quality: This category covers the building’s climate and environmental impacts: life cycle assessment, carbon footprint, embodied energy, resource consumption, and more. It is one of the core pillars of DGNB, aligned with European LCA standards (EN 15978, EN 15804).
• Economic quality: DGNB evaluates life cycle costs, economic durability, and the project’s ability to maintain stable performance over time. This approach responds to the growing need to control operating costs and secure the long-term value of real estate assets.
• Sociocultural and functional quality: This criterion addresses comfort, quality of use, health, and occupant well-being. The objective is to ensure that the building is not only high-performing, but also pleasant, safe, and user-friendly.
• Technical quality: DGNB assesses construction quality, technical robustness, energy performance, and system reliability. This category is a strong indicator of the building’s resilience and structural durability.
• Process quality: This set of criteria evaluates design quality, project management rigor, documentation, transparency, and risk management. It ensures that a sustainable building project is supported by a sustainable methodology.
• Site quality: Finally, DGNB analyzes how the building integrates into its surrounding environment: mobility, infrastructure, density, adaptability, and urban quality. This is a key dimension to ensure that a sustainable building is part of a sustainable territory.

Thanks to these six dimensions, DGNB goes beyond certifying a “green” building and instead measures its overall quality, long-term impact, and actual performance.

Focus: carbon and materials criteria

Environmental impacts

DGNB assesses the building’s environmental impacts through a comprehensive life cycle assessment, covering modules A1–A3, A4, A5, B4, and C in accordance with EN 15978.

As a reminder:

• A1–A3: product stage (raw material extraction, transport, manufacturing)
• A4: transport to the construction site
• A5: construction/installation process and waste generated on site
• B4: replacement of components during the use phase
• C: end of life (demolition, transport, waste processing, disposal)

👉 This makes it possible to measure all impacts related to materials, from raw material extraction to the building’s end of life, including transport, installation, and replacement phases.

The assessment covers a wide range of environmental indicators, making DGNB a particularly comprehensive multi-impact certification framework:

Resources and circularity

DGNB addresses resource use and circularity through two key criteria: ENV2.2 – Responsible use of resources and TEC1.6 – Disassembly and recyclability. The objective is not only to assess the quantity of resources mobilized, but also the building’s ability to be integrated into a more circular material loop.

A key distinction made by DGNB concerns reuse: reused materials are considered existing resources and therefore do not carry the carbon impact of their initial production. Only the processes required to restore or prepare them for reuse are accounted for. This approach directly encourages impact reduction at the production stage and strongly promotes reuse strategies in building design.

DGNB values design for disassembly through a “layer-based” analysis (functional layers: structure, envelope, finishes, technical systems). This method makes it possible to identify components that can be separated, reversed, or replaced without heavy demolition, and above all to make visible and measurable design efforts that are often undervalued in other assessment methods.

This approach contributes to a better consideration of impacts related to replacement (module B4) and end of life (module C).

The framework also takes into account the recycling and recovery potential of materials: recyclability rates, avoidance of incompatible material mixtures, mechanically fixed systems rather than glued assemblies, materials sourced from certified supply chains, etc. The aim is to maximize resource recovery at end of life and to reduce waste generation at all stages of the project.

Finally, DGNB includes the total mass of materials mobilized, making it possible to quantify the building’s material intensity. This assessment encourages lean design, optimized structures, and the selection of lightweight or low-impact materials to reduce the building’s overall footprint.

Embodied energy

→ Embodied energy refers to all environmental impacts associated with materials before and after the use phase: extraction, processing, manufacturing, production, transport, installation, maintenance, and end-of-life treatment (with the notable exception of the operational use phase).

By integrating all these phases, DGNB enables a precise assessment of the actual contribution of materials to the project’s overall impact. Within DGNB certification, embodied energy plays a central role under criterion ENV1.1. This approach highlights the most emission-intensive building elements: load-bearing structure, façades, floor systems, insulation, finishes, and technical equipment. In many new construction projects, embodied energy accounts for more than 50% of total life cycle emissions⁶, making it a major lever for carbon optimization from the very early design stages.

DGNB also requires a comparative analysis of construction variants in order to identify the most effective solutions: mass timber or low-carbon concrete, bio-based insulation materials, recycled steel, lightweight façades, volume optimization, local production, and more. This systematic approach ensures that technical choices are supported by quantified LCA data rather than theoretical intentions.

Finally, embodied energy interacts with other categories of criteria such as durability, circularity, and life cycle costs. As a cross-cutting indicator, it has a strong influence on the final certification level (Silver, Gold, Platinum)⁷ and encourages design teams to integrate high-performance material strategies at a very early stage to reduce the building’s environmental impact.

Material durability

In the DGNB framework, material durability is a cross-cutting criterion that influences life cycle assessment, circularity, life cycle costs, and quality of use. The objective is to assess the ability of materials to maintain their performance over time while limiting maintenance and replacement interventions.

DGNB first analyzes the actual service life of building components. Materials are assessed based on their resistance to moisture, UV exposure, temperature variations, and wear, as these factors directly determine replacement frequency (module B4) and the associated environmental impacts. The longer a material lasts, the more its carbon footprint is amortized over the building’s lifetime.

The framework also places strong emphasis on maintenance. Ease of maintenance, performance stability, and the risk of premature degradation are all taken into account. Materials requiring limited intervention help reduce emissions during the use phase and control operating costs, thereby strengthening their positive contribution to the life cycle cost analysis.

Health performance is also an integral part of the assessment: volatile organic compound (VOC) emissions, indoor air quality, absence of hazardous substances, and compliance with environmental health certifications. DGNB therefore directly links material durability with occupant comfort by integrating these aspects into the sociocultural criteria.

Finally, DGNB values materials sourced from responsible supply chains: certified wood (FSC/PEFC), recycled or recyclable materials, products from short supply chains, or materials manufactured through controlled production processes. These choices enhance the building’s overall durability by improving both technical robustness and environmental performance.

The central role of LCA in DGNB certification

Building LCA integrated into the final score

In DGNB certification, Life Cycle Assessment (LCA) is a structuring criterion. The framework allocates 9.6% to 10.4% of the total score to LCA, depending on the building typology, making it one of the most decisive components of the system. This weighting reflects DGNB’s ambition: to assess a building’s environmental performance across its entire life cycle, rather than focusing solely on energy consumption indicators.

The importance of analysing design alternatives at the concept stage

LCA is not merely a reporting tool; it plays a role from the very early stages of design. DGNB requires that several construction alternatives be assessed and compared in order to identify the most effective solutions across multiple parameters: carbon impact, material mass, durability, ease of maintenance, and life cycle costs.

These alternatives may relate to the structural system (timber, low-carbon concrete, recycled steel), the building envelope, technical systems, or insulation materials. This comparative analysis helps to objectify technical choices and to integrate environmental impact reduction as a true design driver, rather than a constraint addressed after the fact.

Why LCA is essential to achieve Silver, Gold, and Platinum levels

LCA directly determines access to higher certification levels.

• Silver level requires a coherent, compliant, and well-documented LCA.
• Gold level requires clear evidence of optimization: alternatives assessed, choices justified, and measurable impact reductions.
• Platinum level requires not only a high-performing LCA, but also strong consistency with other criteria related to materials, circularity, and life cycle costs.

By using LCA as a cross-cutting tool influencing environmental, technical, and economic aspects, DGNB positions it as a central element in achieving environmental excellence. LCA thus becomes a project steering method, a decision-making basis, and a key factor in improving the building’s overall long-term performance.

The role of engineers in the DGNB approach and optimization through LCA

Within a DGNB Certification process, engineers play a decisive role: they translate the developer’s ambition into a building that truly complies with the requirements of the framework. While the project owner targets a Silver, Gold, or Platinum level, engineers ensure data quality, methodological rigor, and the consistency of construction choices. This work is essential not only to meet regulatory transparency requirements (EU Taxonomy, CSRD), but above all to satisfy the stringent criteria of DGNB, which assesses building sustainability through measurable, life cycle–based indicators.

Engineers are also responsible for the Life Cycle Assessment (LCA), a central pillar of the DGNB framework. They model the building, select materials and their environmental data, calculate carbon impacts and embodied energy, and assess multiple design alternatives to identify the most effective solutions. As DGNB places strong emphasis on material impacts across all life cycle stages, a robust, well-documented, and standard-compliant LCA becomes a mandatory prerequisite for achieving higher certification levels.

Finally, engineers are involved very early in the process, working alongside architects to guide structural and material choices from the initial design phases. This collaboration is essential, as the main carbon reduction levers today lie in construction systems and material choices rather than in the operational phase alone. In other words, the majority of DGNB performance is determined at the moment when the structural system, building massing, construction methods, and insulation strategies are selected. Early involvement makes it possible to integrate low-impact strategies, significantly reduce environmental impacts, and maximize the chances of achieving the highest DGNB Certification levels.

Main pain points encountered

DGNB Certification requires a particularly precise and structured LCA approach, making it one of the most demanding aspects of the framework. The criterion ENV1.1 – Building Life Cycle Assessment represents up to 10.4% of the total score for certain building typologies (notably offices), making it a major performance lever. The LCA must cover modules A1–A3, A4, A5, B4, and C in accordance with EN 15978 (building LCA) and EN 15804 (EPDs), and be based on verifiable environmental data from third-party EPDs. Engineers therefore need to collect and structure large amounts of material data, verify DGNB compatibility, document all calculation assumptions, and deliver a comprehensive analysis integrated into the final score. This methodological rigor, combined with the sensitivity of results to material choices, makes DGNB LCA particularly complex to carry out.

DGNB also requires a comparative analysis of design alternatives⁹, adding a significant layer of complexity. The framework mandates the assessment of multiple construction solutions and the demonstration of their impact on greenhouse gas emissions, embodied energy, and durability across the entire life cycle. Each alternative must be modeled separately, weighted according to DGNB rules, and fully documented for audit purposes. Managing data from heterogeneous international datasets, which may be incomplete or not fully aligned with EN 15804, further complicates the process. In practice, building multiple models, updating them, and verifying their compatibility represent one of the major pain points of the DGNB process.

Finally, many teams still carry out DGNB LCA using manual workflows, often based on Excel spreadsheets and multiple file versions. These processes generate a high risk of errors (units, conversions, quantities, weighting factors, EPD mapping), slow down iterations, and make it difficult to justify design choices during audits. DGNB, which requires extreme precision and comprehensive documentation, is poorly suited to such manual tools. This is precisely where solutions like Vizcab deliver decisive value: automated data structuring, compliance with LCA standards, smooth management of design alternatives, automated recalculations, and a drastic reduction in inconsistency risks—key assets for meeting the technical and methodological requirements of the DGNB framework.

Checklist — How engineers can optimize a DGNB project

• Integrate LCA from the earliest design stagesTo quickly guide key structural decisions and reduce carbon impacts before choices are locked in.
• Anticipate the impact of materials on embodied carbonBy identifying the most contributing elements (structure, façades, insulation) in order to target the most effective reduction levers.
• Secure the quality and compliance of environmental data (EPDs)By verifying alignment with EN 15804 standards and DGNB requirements to ensure the reliability of the LCA.
• Assess the durability, disassemblability, and service life of componentsTo optimize performance across the entire life cycle, in line with the framework’s durability and circularity criteria.
• Integrate life cycle cost (LCC) analysis into technical trade-offsTo align construction choices with environmental performance and the project’s economic viability.

How does Vizcab facilitate DGNB LCA?

DGNB-compliant structure

Vizcab natively integrates the LCA structure expected by DGNB: modules A1–A3, A4, A5, B4, and C, full alignment with EN 15978 and EN 15804, classification compliant with the German DIN 276 standard, consistent units, and full traceability of assumptions. The tool is based on general input data describing the building, covers all required LCA phases, and integrates the energy and refrigerant data expected by the DGNB framework.

This built-in compliance directly reflects one of our key strengths highlighted during testing: greater transparency and accuracy in how the LCA is structured and documented, with DGNB-compliant Excel exports (Table 8 and Table 9) and direct comparison with regulatory thresholds, whereas other tools tend to be more opaque or spread information across multiple modules.

Thanks to this embedded rigor, engineers can produce a reliable, audit-ready DGNB LCA, while minimizing the risk of methodological errors—one of the most recurring pain points identified in user feedback.

International data

DGNB requires robust, verifiable environmental data that comply with EN 15804. Vizcab primarily relies on the core reference databases used in DGNB practice, notably IBU and Ökobaudat, which serve as benchmark databases for building environmental assessment within the DGNB framework.

The platform also provides access to an open and transparent international database, ensuring full visibility on EPD sources, underlying assumptions, and calculation methods. To offer maximum flexibility to users, Vizcab additionally allows the use of data from other recognized program operators (The International EPD System, EPD Norway, EPD Denmark, INIES, BRE, etc.), all directly selectable via the DGNB search panel.

This openness has been confirmed as one of Vizcab’s strongest competitive advantages during the independent audit: users immediately understand which data are being used and how they influence the results, which is not always the case with competing tools.

This approach strengthens both the reliability and traceability of LCAs, two essential criteria for DGNB audits, which pay close attention to data sources and their methodological consistency.

Fast modeling

Vizcab is designed to enable DGNB modeling 2 to 5 times faster, according to comparative testing feedback. Thanks to its intuitive interface and the integrated Material Quantity Generator (MQG), engineers can:

• start the LCA from the earliest design stages,
• progressively refine quantities and EPDs,
• test multiple construction alternatives without recreating the study,
• maintain a single, continuous workflow from concept to detailed design, a key differentiator identified by testers.

This speed and flexibility are among the most frequently cited user benefits: less complexity, fewer clicks, more iterations, and faster decision-making.

In a framework like DGNB, where comparative analysis is mandatory and carbon performance depends on successive design alternatives, this ability to iterate quickly becomes a decisive advantage.

1 : https://my.dgnb.de/de/news/meilenstein-mehr-als-1000-dgnb-auditoren-ausgebildet
2 : https://www.dgnb.de/en/dgnb/about-dgnb/dgnb-in-figures
3 : https://ausschreibungen-deutschland.de/2028206_Berlin_TXL_-_UTR_-_Beratung_und_Planung_DGNB-ZertifizierungReferenznummer_der_Bekanntmachung_2023_Berlin
4 : https://www.dgnb.de/en/certification/dgnb-certified-projects/project-details/berlin-txl-the-urban-tech-republic-campus-wes
5 : https://journal-buildingscities.org/articles/10.5334/bc.257
6 : https://building-material-scout.com/en/sustainable-building/building-certification/dgnb-criteria/?utm_source=chatgpt.com
7 : https://www.dgnb-navigator.de/en/life-cycle-assessment