Flammable trees of the species that stoked the Table Mountain fire last month could be turned from a fire hazard into a fireproof material and revolutionise building in informal settlements, curbing the runaway fires that kill dozens of people every year.
Nomasamson Dlamini was the latest victim. She died in an inferno in Cato Crest, Durban, which burnt down 50 shacks in the same week that the wildfire torched heritage buildings at the University of Cape Town (UCT) and forced widespread evacuations.
"The fire-prone alien trees around UCT, which should be felled, could be used to build houses to upgrade informal settlements or even as fireproof 'starter packs' to rebuild burnt homes," says conservationist Guy Preston.
More than 5,000 informal dwellings burnt down in a single year, the Fire Protection Association of Southern Africa said in 2017.
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Preston retired in June as deputy director-general in the department of forestry, fisheries & the environment, where he drove 14 programmes employing more than 70,000 people, including Working on Fire. He initiated the ground-breaking Value-Added Industries Programme, with which he is still involved.
The programme's foundation is a biomass-insulated concrete (BIC). This innovative mixture, made of 75% alien plant biomass, has been proved to be fireproof for at least three hours in certification trials.
BIC was born out of experimenting with alternatives to wood-wool cement board, from which the first trial "fireproof" houses were built but which was too expensive.
A fire test was conducted with this new board in Tshwane in 2016, led by then mayor Kgosientso Ramokgopa. Officials were so confident the double-storey building would not burn that two staff members and metro firefighters were inside the whole time.
Nine shacks doused in petrol were put around the house and set alight. They burnt down in seven minutes, while a shack lined with the board did not burn down. The house had no damage besides two cracked windows.
This type of fireproof and airtight house could be a refuge in a settlement fire or wildfire, which is dangerous to try to outrun.
Invented by engineers and designers in the department, BIC also offers a shield against heat and cold from outside, a benefit tested in trials, including recently in two research houses in the Kruger National Park.
Danny Govender, the general manager of the Savanna & Grassland Research Unit in Kruger, said: "The design is super comfortable. This environment gets very warm and we want to check out if the thermal buffering [from BIC] means we will not need aircon."
The fireproof properties of the huts, about the size of an RDP house, could be put to the test as fires in the savanna areas of Kruger are not uncommon, Govender said.
At the other extreme, on Gough Island in the icy South Atlantic Ocean, is an emergency hut built of a wood-plastic composite in 2019. This is another product trial to turn biomass from invasive trees and waste plastic into high-quality housing.
The visionary programme to use biomass for value-added industries had its origins in 2005, when invasives cleared to prevent fires and protect water sources were used to make eco-coffins.
But that initiative was not making much of a dent in the number of invasive trees cleared, and the department turned its attention to making eco-desks for schools, benefiting more than 700,000 pupils.
This was still not consuming much of the invasive biomass, so designers and engineers in the programme developed the novel material and designed multistorey green houses.
When more than 100 trials had produced an Agrément-certified BIC product, Preston was asked to build toilet blocks to replace pit latrines in schools as part of the Sanitation Appropriate for Education programme.
Mapitsi Mokete, deputy principal of Kgoogo Primary School in Limpopo, said they received new toilets for about 500 pupils, teachers and visitors last year. "They have made a great difference. Before, we had pit toilets," said Mokete.
Another bonus is that building with BIC is calculated as carbon-neutral, adding momentum to the green-build trend. Talking about the potential of BIC, Preston said: "This is our greenest option for building. By using invasive plants in the BIC material we help to address the invasions, the single biggest threat to South Africa's water security and biological diversity, and causes wildfires."
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