Block Research Group goes fully circular in South Africa.

The Indovlu floor is a rib-stiffened, discrete funicular shell made with unreinforced, lightweight biomass concrete mix, containing wood fibres from invasive alien plant species that threaten South Africa's freshwater supplies and increase the risk of wildfires.

The floor was developed through a collaboration with external page Stephen Lamb and Andrew Lord, co-founders of external page nonCrete, Cape Town based company producing low-carbon, biomass concrete mix, and as part of “Alien to Biomass Housing” project, co-funded by CSIR’s Circular Economy Fund and WWF’s Nedbank Green Trust, and led by Prof. Linda Godfrey. Special thanks go to the enthusiastic One Nil team for their help throughout the project.

Compared to conventional concrete, nonCrete mixes use fewer scarce resources (sand and conventional aggregates), instead incorporate local, renewable biomass, are 55% to 65% lighter, with carbon permanently sequestered within the biomass. The mixes show excellent thermal insulation and fire resistance properties.

The result is a structural system that embodies BRG's principles of “Strength through Geometry” and “Material Efficiency”, with the potential to revolutionise current building practices in South Africa while also creating local job opportunities. Indlovu floor is now on fast track towards full building certification.

Full project details and credits can be found on the BRG’s project page, and if you would like to meet nonCrete’s founders in person, then join the upcoming Sustainable Built Environment Conference (SBE25), which they are part of. The conference takes place at ETH Zürich from 25 to 27 June 2025.