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Development and Demonstration of Highly Insulating, Construction Materials from Bio-derived Aggregates

Periodic Reporting for period 3 - ISOBIO (Development and Demonstration of Highly Insulating, Construction Materials from Bio-derived Aggregates)

Reporting period: 2018-02-01 to 2019-01-31

Energy consumption associated with the built environment can be separated between construction materials and heating in use, it is possible to appreciate the relative impact that these have on the environmental impact of the construction sector. As energy consumption reduces towards the target of 15kWh/m2/annum, so the relative impact of construction materials increases from an 8% to 60%, based on a 100 year life-span. It is therefore an important issue that will affect the market for construction materials in the near future, whether for new build or for the renovation of existing buildings.

To reduce the energy required for construction purposes it is necessary to develop new materials that demand less energy during their manufacture and assembly. Bio-sourced materials for construction have been widely and successfully used for centuries. However, these materials are not used in mass or large construction projects, where industrial scale, high volume, low cost, high embedded energy materials dominate. Globally this sector had an annual value of €2.4 trillion in 2012 and accounted for 40% of man-made CO2 emissions. In the European Union, the built environment accounts for 40% of energy consumption and 36% of CO2 emissions, of which heating and cooling account for 60% of those emissions. The challenge of decarbonising construction is a significant one and is not being met by conventional construction techniques and materials.

Against this backdrop, a new class of low environmental impact construction materials ‘eco-materials’ have become important in the struggle against global warming. The ISOBIO project aims to identify, evaluate and assess the available bio-based aggregates and binders to enable the selection of the most effective constituents which can then be assembled into novel composite materials. The performance of these composite materials can then be measured and compared with their conventional counterparts.

The specific objectives of the ISOBIO project are to produce novel, fully functioning vapour permeable panels and wet applied materials, that are 20% more insulating and will deliver a reduction in embodied energy of 50% compared to conventional materials. To encourage adoption of these materials the aim is for them to have a whole life cost no more than 85% of comparative current materials.

The sustainable materials under development in the ISOBIO project do not contain or use in their manufacture volatile organic compounds (VOCs). In addition, their high porosity provides a moisture buffering effect which can help to regulate humidity and prevent rapid and significant variations. These characteristics will help in enhancing the quality of air within buildings and are expected to reduce the risk of condensation and mould growth.

The validation of the performance of components made from these sustainable materials will allow the European SMEs involved in the project to demonstrate the advantages of these products, providing them with a competitive advantage.
The most significant results of the ISOBIO Project consisted of:
• Creation of a novel bio-based insulation material with some highly interesting characteristics including:
o Lightweight and rigid, with higher strength than competitive products
o Capable of acting as a render carrier
o Resistant to fire
o Excellent moisture buffering capability
o Low thermal conductivity combined with high specific heat capacity
o Capable of high-volume manufacture in a continuous process
o Lower cost than competitive products

This product is now ready for scale-up and CAVAC, the manufacturing partner, are developing approaches to take this exciting material to full-scale production and marketing.

• Creation of a novel insulating render system with some highly interesting characteristics including:
o Lightweight render with low thermal conductivity
o Cost-effective and straight-forward to apply
o Resistant to fire

This product is now ready for scale-up, and BCB, the manufacturing partner, will be adding it to their product line for marketing and sale in France and elsewhere in the EU.

• Creation of a novel insulating clay plaster with some highly interesting characteristics including:
o Lightweight plaster with low thermal conductivity
o Cost-effective and straight-forward to apply
o Resistant to fire
o High moisture buffering capability

This product is now offered as part of the range of clay plasters being manufactured and marketed by CLAYTEC, the manufacturing partner.

From a scientific point of view, the work undertaken by the research partners has led to the development of new characterisation techniques for use with bio-based materials, and a deeper understanding of the structure and hygrothermal performance of bio-based aggregates. The development of hygrophobic and fire resistant nano-coatings using the sol-gel process has advanced our knowledge and understanding of the use of this process with bio-based materials. These insights have been published in peer reviewed journals, and will be used by the scientific community to further develop the use of bio-based materials in the field of construction.

The communication efforts have helped to widely promote the project. They have included a combination of active social media presence, wide-ranging journalistic articles and engaging communication materials. The production of a Video News Release, which was taken up by 11 TV stations, helped to bring the ISOBIO results into the living rooms of Europeans.

Project partners have been extremely active in disseminating the project results. This includes journal papers, conference presentations, exhibitions, stakeholder events and bilateral meetings. In the final period this included exhibiting at the ECTP conference in Brussels, the production of a construction details manual by Progetic, and a final project event held in Brussels.

• 17 peer-reviewed scientific papers in international journals
• 30 conference papers
• 59 presentations of ISOBIO results to…
• 5000+ stakeholders at international conferences
A systematic assessment of both commercially available bio-based building products and key raw materials has been undertaken. This assessment provides a unique database of biogenic materials, their construction relevant properties and environmental footprints. The assembly of these raw materials into composite core structures is enabling a materials-by-design approach to be developed. Both biogenic and mineral binders are being used to provide a toolkit of composite materials and their key characteristics. Novel chemistries are being developed to provide high levels of water repellence to enable products with durability to external conditions, and to improve the fire resistance of these composites.

Adoption of bio-based materials for the construction sector is dependent on many factors including material performance (real and perceived), availability, cost, regulatory incentive. The ISOBIO project is establishing a database of raw materials and composites, a full environmental assessment of key products and appropriate test methods that enable the advantages of bio-aggregates to be quantitatively measured and compared with conventional materials.

These steps are aimed at providing a robust platform to enable the industrial partners to take the emerging products to the market-place by overcoming many of the barriers to adoption that currently exist.
Hemp panel with lime renders
CAVAC Hemp panel
Hemp shiv binded with waterglass and treated with TWI repellent treatment
Compsite panel samples: Hemp shivs- Hemp fibres
ISOBIO at Ecobuild 2018