Measuring Circularity, Reducing CO₂ with Madaster

Blogs 15 oct 2025

The construction industry is responsible for nearly 40% of global carbon emissions. A large share comes from embodied carbon, the emissions linked to the production, transport, and use of building materials. Unlike operational energy, which can be decarbonized over time with renewable energy, embodied carbon is “locked in” at the point of construction.

This is where circular construction can make all the difference. By documenting, reusing, and optimizing materials, the sector can significantly reduce its environmental footprint.

Without the right data in place, we cannot understand the impact of our operations and act on them. This is exactly why Madaster was created: to measure and manage carbon emissions, supporting alignment with the net-zero targets.

How Madaster supports CO₂ reduction

Madaster makes circular construction practicable and measurable by:

Registration and documentation: Every material used in a building is logged, including an automated calculation of its CO₂ impact across life-cycle phases (A to D).
Material comparison: Designers, contractors, and owners can compare materials based on embodied carbon. Timber vs concrete, new vs reused — the impact is visible, encouraging better choices.
Access to analytics: Detailed data supports certifications like DGNB and BREEAM, as well as international investor frameworks such as CRREM. Users can also explore alternatives when a product shows high embodied carbon.

The Ellen MacArthur Foundation estimates that circular construction can cut CO₂ emissions by up to 38% compared to linear construction. With Madaster, these reductions become quantifiable.

Measurable outcomes from circular construction

Madaster provides project teams with insights at both the building and portfolio level:

Circularity Index – shows reuse potential in line with industry standards.
Disassembly potential – assesses how easily products can be separated for future reuse.
Environmental impact – evaluates CO₂ and other factors such as freshwater use.

Real-world applications:

Design-stage comparison

A European property developer used Madaster to model two scenarios for a new apartment complex: one with a traditional concrete structure and one with a timber structure.

The developer was able to visualize the difference in embodied carbon by registering and analyzing material data for both options. The results helped the team justify the choice of timber, which would mean a decrease in upfront emissions and increased reuse potential for the building at the end of its life.

Sustainable procurement

A national drinking-water utility integrated Madaster into its procurement process. Suppliers bidding for infrastructure projects were required to register material passports on the platform. This ensured that every product could be assessed on cost, performance, as well as circularity and CO₂ impact. The utility was able to compare suppliers based on verifiable data, ultimately rewarding those offering more sustainable, low-carbon solutions.

Investor compliance
A real-estate investor turned to Madaster to streamline reporting under the EU’s Corporate Sustainability Reporting Directive (CSRD). The investor registered the portfolio’s assets in the platform and gained instant access to metrics on embodied carbon, circularity potential, and environmental impact. This supported compliance with the new regulations, as well as demonstrated to stakeholders and financiers that the portfolio was aligned with sustainability standards — thereby increasing long-term investment appeal.

Quantifying embodied carbon savings

On average, 1 m² of floor area contains 500 kg of embodied carbon. Circular principles can reduce this to 310 kg — a 38% reduction.

Madaster has already registered 30 million m² of buildings across Europe. That represents a potential saving of 9.3 megatons of CO₂.

Applicable to both new and existing buildings

Circular construction isn’t just for new builds. Existing buildings also benefit when materials are documented, analyzed, and prepared for reuse.

New construction: Teams can compare options and select low-carbon materials in the early stages.

Existing buildings: Teams can identify reuse opportunities for materials even with limited data.

Scaling impact across countries

Madaster is active across Europe and the UK and is expanding globally. Our growth model aims to onboard 30 new clients annually. If each works on three projects of 5,000 m² and saves 200 kg of CO₂ per m², that adds up to 90 million kilograms of CO₂ saved per year.

Conclusion

Reducing building carbon emissions requires data, documentation, and transparency. Madaster delivers the tools to make circular construction measurable, enabling the construction sector to move toward a low-carbon, resource-efficient future.