Community Research and Development Information Service - CORDIS


ISOBIO Report Summary

Project ID: 636835
Funded under: H2020-EU.

Periodic Reporting for period 1 - ISOBIO (Development and Demonstration of Highly Insulating, Construction Materials from Bio-derived Aggregates)

Reporting period: 2015-02-01 to 2016-07-31

Summary of the context and overall objectives of the project

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.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The project has followed a materials-by-design methodology. A survey of the commercially available bio-aggregates has been undertaken to provide an assessment of the market place. A total of 231 products from 66 different manufacturers were identified and were categorised according to composition, form and functional use and indicating their advantages and disadvantages. Detailed examination and characterisation these bio-aggregates has been carried out using a range of analytical and measurement methods. Existing testing standards have been used, but new assessment methodologies are also being developed to allow some of the key properties of these sustainable materials to be properly measured. The design and development of novel surface treatment to bio-aggregates such as hemp shiv has been shown to provide significant improvements to the repellence of liquid water. Some impact on the moisture buffering capability of the treated hemp shiv was measured but this was not viewed as being significant. A range of mineral binders including clay and lime based products as well as sol-gel derived hybrids have been identified and included into the composite material fabrication activity of the project. Preliminary methods to improve the compatibility between the mineral binders and the organic bio-aggregates have been established, as has a novel method to reduce the carbon footprint of the lime based binders. Bio-sourced binders have also been examined. These range from non-additive methods such as lignin release under hydrothermal conditions through to the introduction of specific bio-derived materials such as waste products from paper or certain food manufacturing processes.

A wide range of composite materials have been produced, some with thermal conductivity values as low as 51mW, many with hygric properties fall into the excellent category with moisture buffering values in excess of 2g/m2.%RH. External renders and plasters based on natural materials that provide water repellence and mechanical and environmental durability for exterior applications whilst also being sufficient vapour permeable to enable the moisture buffering capabilities of the composite to be utilised are under development.

The partners have determined that a link between reference building elements and their bio-derived counterparts does not exist. Therefore ISOBIO has proposed an outline performance specification for bio-derived materials for different wall constructions. This provides a basis for the development of components for natural material based prototype panels such as those being developed in ISOBIO.

Considering existing construction materials from a life cycle analysis perspective, the identification of the commercially available bio-aggregates has been included in the systematic collection of environmental data for all insulating materials. A critical review has been undertaken which has resulted in the preliminary conclusion that environmental product declarations for biogenic-based insulation is often not available, although this is changing. In some Environmental Product Declarations there is already data given for the embodied energy, but in many (especially those in EN15804 format) this is not explicitly stated. Where the EN 15804 format has been followed, the embodied energy can be calculated by the summation of two impact categories:
• use of renewable primary energy excluding renewable primary energy resources used as raw materials
• use of non-renewable primary energy excluding non-renewable primary energy resources used as raw materials

One major result of WP8 is the analysed effect that insulation materials based on bio-aggregates appear inferior to several comparable synthetic materials if sequestered carbon is excluded from the calculation of CO equivalents. This clearly places these materials at an unfair disadvantage and may require revision of standards such as EN15804.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

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.

Related information

Follow us on: RSS Facebook Twitter YouTube Managed by the EU Publications Office Top