Use waste as resource, Rethink the business model
9Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation
11Make cities and human settlements inclusive, safe, resilient and sustainable
Urban development means removing many tonnes of soil and rubble, which mostly treated as waste and dumped in expensive landfill sites. Construction waste constitutes an average of 30% of all waste that goes to urban landfills. At the same time, there is a huge deficit of housing in South Africa’s urban centres where alternative construction materials can fill a gap.
What if we were to start thinking of construction waste as a resource, in the same way as the packaging that is sent to landfill?
USE-IT is an eThekwini (Durban) based non-profit company that focuses on waste beneficiation, with the aim of diverting substantial volumes from landfill and creating sustainable employment opportunities and viable private sector investment.
RamBrick is a compressed earth block application using waste soils from construction and development sites and crushed rubble to manufacture blocks for housing construction. The RamBrick is composed of a blended mixture of 70% waste soils, 25% crushed builders rubble and 5% cement stabilizer. They are made without water, using a hydraulic compression system to press the waste materials into blocks that are subsequently air cured, creating a very low-embodied building material (251 kg CO2/m2 compared to concrete blocks at 760 kg CO2/m2).
The RamBrick offers two main benefits: firstly, landfill diversion. Urban centre landfills are rapidly filling up and it makes no sense to use an expensive engineered lined landfill to store inert waste materials. Secondly, the RamBrick is highly thermally efficient, bullet-proof, sound-proof, cheaper (16% cheaper than concrete blocks and 45% cheaper than clay bricks), requires zero water in manufacturing, and has a very low embodied energy.
The idea behind the RamBrick was to create new enterprises to divert waste from landfills and manufacture blocks for the gap in the housing market. RamBrick’s work has been supported through partnerships with the eThekwini Municipality (Durban), and the Development Bank of South Africa through the country’s Jobs Fund and the Green Fund.