Grant: Alliance Grants

This international collaboration aims to develop and optimize a new class of lightweight biocomposite materials for low-carbon and energy-efficient buildings. Canada and Chile are among several countries faced with the challenge of simultaneously reducing carbon emissions while significantly increasing the housing supply and associated infrastructure. The building sector is responsible for one-third of carbon emissions globally. Therefore, new buildings must employ effective decarbonization strategies associated with both the embodied energy of building materials and the operational energy of the completed building. Biocomposite materials with renewable plant-based ingredients present a promising solution. Lignocellulosic materials, such as hemp, flax, and wood particles, are abundant waste materials in the agriculture and forestry industries with low embodied energy and carbon sink properties7 that can be mixed with mineral binders (lime, cement, pozzolans) and water to create bio-based composites with excellent thermal insulation and storage properties. Well-known bio-based materials such as hemp-lime composites (also called hempcrete) possess good insulating properties and high renewability, while they can absorb and sequester CO2 when incorporated into building envelopes. However, commercial hemp production is still illegal in many countries, including Chile. Furthermore, while the hemp market is growing, the current North American supply of hemp straw is insufficient to compete with conventional resources used for insulation production. Challenges related to standardization and conformity of natural materials within different local contexts have also slowed adoption. There is a growing need to: 1) explore new types of biocomposites to identify suitable plant-based alternatives with similar-or superior-properties to hemp using waste byproducts from local agriculture; 2) develop robust quality control practices and mix design methodologies to make them viable for widescale adoption; and 3) link plant cell structure and physical/chemical properties with overall constructability and performance of building assemblies.