New findings published in the journal Construction and Building Materials from a team of materials researchers working at the University of British Columbia Okanagan's School of Engineering have demonstrated the sustainable qualities of using wood fly ash by-products as alternatives to traditional concrete additives. 

The study was undertaken in light of some recent popularity of rammed earth construction in the architectural field, an ancient form of building whose mastery has propelled the 2022 Pritzker Prize winner Diébédo Francis Kéré and several others to prominence parallel with the industry's fight against climate change. 

"Everything old is new again and that is precisely why we've been investigating rammed earth construction," Dr. Sumi Siddiqua explained to the UBCO news outlet. "There is an increasing demand for sustainable building products here in Canada and around the world, and materials like fly ash are just the start of a new and important trend."

Siddiqua’s team was part of a larger initiative with BC Housing and UBC's Build Better Cluster that partners with Indigenous communities in the region to integrate rammed earth methods into newly constructed homes.

Different combinations of wood fly ash, cement, and calcium bentonite were tested to achieve an optimal variation for each (hot and cold) condition of outdoor climate and humidity levels.

The researchers claim this will help combat a "lack of understanding of the influence of fly ash" that affects architects and the building trade. They say the combination of cement, wood fly ash, and bentonite researched and their correlation to improved thermal qualities of rammed earth has heretofore not been tested. The work will have particular bearings on sandy soil environments and will be interesting to follow as a further development in the future.