upCeiling – upcycling of recycled aggregates in earth screed for circular ceilings

AI Quick Summary

Ceiling systems are responsible for approx. 40% of CO2 emissions in buildings. Due to requirements regarding sound insulation, the individual construction layers are often firmly connected to each other and non-reversible cement-based screed is used. An innovative, circular timber-earth ceiling system is to be further developed. The basic concept of the system has been outlined within a 4-year EU research project (GreeNest) funded by the EU and SERI.The goal of the Booster is to focus on recycled aggregates and binders for the development of a circular screed. This aims to demonstrate new applications for recyclates while also reducing the use and extraction of primary raw materials. The screed provides sound insulation, can accommodate building services (temperature regulation), and enables adaptability during renovations. The service life of buildings is significantly extended, as building services can be installed, maintained, and replaced from above without the need for demolition and disposal. a. What challenge in the circular building and construction industry does your idea address?Ceiling systems cause approx. 40% CO2-emissions in construction. Due to requirements (noise, fire) components are joined irreversibly and make maintenance, repair, adaptations (service life) or reuse (end of life) difficult to realize. Additionally, the integration of building services in cement-based materials intensifies these challenges.b. What is your vision for solving this challenge, and why is your approach innovative? Who will benefit from a solution to this problem?The circular ceiling construction based on upcycled earth screed reduces significantly CO2 emissions, primary resource demand but also maintenance cost. Additionally, the earth screed enables adaptive reuse and extends the service life of the building elements. Building owners, tenants and construction companies will benefit from the cost-efficient innovation.In the last decades the construction industry developed traditional crafts and natural materials into highly industrialized techniques and optimized building products. The list of ingredients of most of the building products is no longer limited to a simple choice of materials but contains many substances which are ‘improving’ the processability to reduce execution time. Unfortunately, many of those additives that are used in modern construction materials are later identified as hazardous substances in construction demolition waste (CDW). The use of earthen building materials as the only mineral circular building material can store material in the future building stock since it’s possible to reuse the material endlessly. So the waste volume can be reduced. c. How could your idea positively impact the planet, people, or economy in the future? (e.g., circularity, reducing waste, improving health, creating opportunities)Earth as intrinsic circular construction material reduces CO2 emissions in construction. The developed earth screed, based on recycled minerals will make use of a former waste product, provides new application cases and reduces extraction of primary ressources. Additionally, the use of earthen building materials increases the reusability of building elements or components in the building stock. With a framework developed in the project manufacturer can adapt to new building methods and meet the requests of Zero Emission Buildings. There are already companies who shift parts of the production infrastructure to earthen building materials improving their energy consumption. d. What assumptions or ideas do you want to test? What do you plan to work on during the booster program, and what is your goal to deliver at the end? (e.g., feasibility testing, prototype development, testing desirability)In circular construction the topic of pollutants and mechanical properties has to be addressed. Hazardous substances can accumulate in the fine fractions of recycled mineral materials. For the application in screed aggregates from 2-8 mm are needed in the mixture. This fraction can be provided by recycled aggregates while the binder is provided by excavation. The project team will investigate whether it’s possible to substitute primary raw materials in earth screed mixtures while reaching the same mechanical properties in comparison to primary raw materials. Furthermore, the topic of harmful substances shall be addressed to make sure that they will be excluded.Additionally, the service life of the element shall be tested and its potential impact on life cycle costing. Therefore, ease of application, a maintenance regime and reuse at the end of live shall be investigated to prove the possibility of multiple service lifes of the element and associated cost reduction.At the end of the development a large-scale prototype shall deliver proof of concept. The successful development could enable the opportunity to apply the ceiling element in a real case demonstrator.e. Has your idea been tested before? If yes, what were the results, and what remains to be tested?In the GreeNest project – ‘Nest Ingrained Ecosystem for Zero Emission Buildings’ funded by the EU and SERI, the ceiling system is tested with the use of primary raw materials for the earth screed. The application in a demonstration building is still pending and scheduled for 2026. The use of recycled aggregates in the mixture needs to be investigated in the framework of the CBI Booster. f. Who is in your team, and what expertise or roles do they bring? (max. 150 words)Andrea Klinge, Professor for Circular Construction, expert in earth and timber construction | INEBJulian Mönig, M.Sc. Architect, Expert in earthen construction | INEBThe Institute Sustainability and Energy in Construction (INEB) at the University of Applied Sciences Northwestern Switzerland is one of the leading Swiss institutes in applied research in over 25 years. It deals a.o. with sustainable planning and construction, resources for efficient and circular construction and healthy buildings, indoor air quality in education and training, research and in projects with practice partners. Christiane Löffler, Dipl.-Ing. Architektin, Erdkundlerin | IG LehmIG Lehm, the Swiss Earth Association, the professional association for earth construction in Switzerland. Earth building experts from the fields of consulting, planning, execution and building material sales come together to independently and jointly promote and further develop building and design with earth as a building material.g. How do you plan to secure the 10% third-party funding required? (max. 100 words)The 10% third-party funding is secured by a private company that provides the recycled aggregates for the development of the upcycled earth screed. If additional third party funding is needed this will be provided by INEB.

Project Idea Metadata

• Project Idea Name: upCeiling – upcycling of recycled aggregates in earth screed for circular ceilings
• Date: 4/9/2025 9:07:00 PM
• Administrators:
  • Julian Mönig

Project Idea Description

a. What challenge in the circular building and construction industry does your idea address?

Ceiling systems cause approx. 40% CO2-emissions in construction. Due to requirements (noise, fire) components are joined irreversibly and make maintenance, repair, adaptations (service life) or reuse (end of life) difficult to realize. Additionally, the integration of building services in cement-based materials intensifies these challenges.

b. What is your vision for solving this challenge, and why is your approach innovative? Who will benefit from a solution to this problem?

The circular ceiling construction based on upcycled earth screed reduces significantly CO₂ emissions, primary resource demand but also maintenance cost. Additionally, the earth screed enables adaptive reuse and extends the service life of the building elements. Building owners, tenants and construction companies will benefit from the cost-efficient innovation.

In the last decades the construction industry developed traditional crafts and natural materials into highly industrialized techniques and optimized building products. The list of ingredients of most of the building products is no longer limited to a simple choice of materials but contains many substances which are ‘improving’ the processability to reduce execution time. Unfortunately, many of those additives that are used in modern construction materials are later identified as hazardous substances in construction demolition waste (CDW). The use of earthen building materials as the only mineral circular building material can store material in the future building stock since it’s possible to reuse the material endlessly. So the waste volume can be reduced.

c. How could your idea positively impact the planet, people, or economy in the future? (e.g., circularity, reducing waste, improving health, creating opportunities)

Earth as intrinsic circular construction material reduces CO2 emissions in construction. The developed earth screed, based on recycled minerals will make use of a former waste product, provides new application cases and reduces extraction of primary ressources. Additionally, the use of earthen building materials increases the reusability of building elements or components in the building stock. With a framework developed in the project manufacturer can adapt to new building methods and meet the requests of Zero Emission Buildings. There are already companies who shift parts of the production infrastructure to earthen building materials improving their energy consumption.

d. What assumptions or ideas do you want to test? What do you plan to work on during the booster program, and what is your goal to deliver at the end? (e.g., feasibility testing, prototype development, testing desirability)

In circular construction the topic of pollutants and mechanical properties has to be addressed. Hazardous substances can accumulate in the fine fractions of recycled mineral materials. For the application in screed aggregates from 2-8 mm are needed in the mixture. This fraction can be provided by recycled aggregates while the binder is provided by excavation. The project team will investigate whether it’s possible to substitute primary raw materials in earth screed mixtures while reaching the same mechanical properties in comparison to primary raw materials. Furthermore, the topic of harmful substances shall be addressed to make sure that they will be excluded.

Additionally, the service life of the element shall be tested and its potential impact on life cycle costing. Therefore, ease of application, a maintenance regime and reuse at the end of live shall be investigated to prove the possibility of multiple service lifes of the element and associated cost reduction.

At the end of the development a large-scale prototype shall deliver proof of concept. The successful development could enable the opportunity to apply the ceiling element in a real case demonstrator.

e. Has your idea been tested before? If yes, what were the results, and what remains to be tested?

In the GreeNest project – ‘Nest Ingrained Ecosystem for Zero Emission Buildings’ funded by the EU and SERI, the ceiling system is tested with the use of primary raw materials for the earth screed. The application in a demonstration building is still pending and scheduled for 2026. The use of recycled aggregates in the mixture needs to be investigated in the framework of the CBI Booster.

f. Who is in your team, and what expertise or roles do they bring? (max. 150 words)

Andrea Klinge, Professor for Circular Construction, expert in earth and timber construction | INEB

Julian Mönig, M.Sc. Architect, Expert in earthen construction | INEB

The Institute Sustainability and Energy in Construction (INEB) at the University of Applied Sciences Northwestern Switzerland is one of the leading Swiss institutes in applied research in over 25 years. It deals a.o. with sustainable planning and construction, resources for efficient and circular construction and healthy buildings, indoor air quality in education and training, research and in projects with practice partners.

Christiane Löffler, Dipl.-Ing. Architektin, Erdkundlerin | IG Lehm

IG Lehm, the Swiss Earth Association, the professional association for earth construction in Switzerland. Earth building experts from the fields of consulting, planning, execution and building material sales come together to independently and jointly promote and further develop building and design with earth as a building material.

g. How do you plan to secure the 10% third-party funding required? (max. 100 words)

The 10% third-party funding is secured by a private company that provides the recycled aggregates for the development of the upcycled earth screed. If additional third party funding is needed this will be provided by INEB.

Ceiling systems are responsible for approx. 40% of CO₂ emissions in buildings. Due to requirements regarding sound insulation, the individual construction layers are often firmly connected to each other and non-reversible cement-based screed is used. An innovative, circular timber-earth ceiling system is to be further developed. The basic concept of the system has been outlined within a 4-year EU research project (GreeNest) funded by the EU and SERI.

The goal of the Booster is to focus on recycled aggregates and binders for the development of a circular screed. This aims to demonstrate new applications for recyclates while also reducing the use and extraction of primary raw materials. The screed provides sound insulation, can accommodate building services (temperature regulation), and enables adaptability during renovations. The service life of buildings is significantly extended, as building services can be installed, maintained, and replaced from above without the need for demolition and disposal.