Methods, measurement, quick wins
Why embodied CO₂ emissions determine the success of climate targets
When talking about climate-friendly construction, one topic usually dominates: energy efficiency in operation. How good is the insulation? How efficient is the heating? But this perspective falls short. Before a building is even used, it has already caused a significant carbon footprint through the production, transport and processing of building materials. These grey emissions, or embodied carbon, now account for up to 50 per cent of total emissions over the life cycle of modern, energy-efficient buildings. Anyone who takes climate targets seriously must start here.
What is embodied carbon?
Embodied carbon encompasses all CO₂ emissions associated with a building before it goes into operation, including raw material extraction, material transport, manufacturing processes and construction site logistics. While operating emissions can be continuously reduced through better technology, grey emissions are already ‘consumed’ at the start of construction – irrevocably and irreversibly.
In an average residential building, concrete, steel, insulation materials and other materials often generate several hundred tonnes of CO₂ before the first resident moves in. In times of stricter climate targets and limited CO₂ budgets, this is no longer a side note, but a key planning factor.
Methods of measurement: transparency through life cycle assessment
The first step towards reduction is life cycle assessment (LCA). This systematically records all emissions from raw material extraction to demolition. Modern BIM tools enable the automated calculation of embodied carbon as early as the planning phase, making the CO₂ load of every component and every material decision transparent.
Environmental product declarations (EPDs) provide standardised data on the CO₂ emissions of individual building materials. This enables architectural firms and engineers to compare different material options and consciously choose more climate-friendly alternatives. What used to be gut feeling is now a data-based decision.
Material selection as a lever: which building materials really count
The biggest emission drivers are quickly identified, with concrete and steel dominating by far. Cement production alone accounts for around eight per cent of all CO₂ emissions worldwide. There is enormous potential for reduction here:
- Recycled concrete with recycled aggregates saves up to 30 per cent CO₂
- High-performance concretes enable slimmer constructions with less material usage
- Alternative binders such as geopolymers or calcined clay reduce the clinker content
- Wood construction binds CO₂ in the long term instead of releasing it – with the same load-bearing capacity
There are also considerable differences between insulation materials. Natural insulation materials such as wood fibre, hemp or straw often have only a fraction of the grey emissions of conventional plastic insulation materials.
Quick wins in construction: intelligence beats mass
Climate-friendly construction does not necessarily mean doing without tried-and-tested materials; often, more intelligent planning is enough:
- Optimised structures: structurally sophisticated supporting structures require less material for the same performance
- Modular construction methods: prefabricated elements reduce waste and construction site debris
- Material efficiency: thinner ceilings and slimmer supports thanks to more precise calculations
- Reuse: deconstruction instead of demolition – using components for new projects
Reducing the number of underground car parks also saves enormous amounts of concrete and steel. Where possible, above-ground or communal parking solutions should be considered.
Quick wins in practice: Immediately implementable
Some measures can be implemented without additional costs or great effort:
- Optimise concrete recipes: Use less cement by increasing the proportion of fillers.
- Local supply chains: Reduce transport emissions through regional procurement.
- Minimise material waste: Precise planning reduces waste by up to 20 per cent.
- Make grey energy visible: Include CO₂ values in tenders.
- Plan for dismantling: Prepare structures for later dismantling.
Digital tools for CO₂ transparency
Together with B3YOND-IT, 3XPERTS develops digital solutions for CO₂ accounting: BIM-integrated LCA tools, automated EPD databases and real-time dashboards that show during the planning stage which material decisions cause how much CO₂. This makes climate protection a plannable, measurable, comparable and controllable factor.
Advantages at a glance
- Climate protection from day 1: emission reduction even before commissioning
- Cost-effectiveness: material efficiency often also reduces construction costs
- Future-proofing: compliance with upcoming CO₂ limits and ESG requirements
- Transparency: data-based decisions instead of assumptions
- Competitive advantage: carbon footprint as a quality feature in tenders
3XPERTS and B3YOND-IT: Life cycle planning with a focus on climate
As an experienced architecture and engineering firm, 3XPERTS systematically integrates embodied carbon analyses into construction process planning. From the initial design sketch to the material tender, we keep an eye on the carbon footprint and develop solutions that are both ecologically and economically convincing.
Together with B3YOND-IT, we create the digital infrastructure for transparent CO₂ accounting: BIM-based LCA software, automated material comparisons and cloud-based reporting tools for ESG-compliant documentation. The result is buildings that contribute to climate protection not only during operation, but also during their construction. Measurable, verifiable and sustainable.
Would you like to systematically reduce the grey emissions of your projects?
Contact us at info@3xperts.com or via our digital contact form and discover how we can successfully shape your projects and your leadership role together.