Nzambi Matee looked at the plastic waste choking Nairobi’s streets and saw a building material that most people missed. That insight turned into action and has made her one of Africa’s most celebrated entrepreneurs and a globally recognised environmental innovator.
She is one of Crest Africa’s Under 40 most influential leaders in green technology and sustainable innovation.
Nzambi Matee grew up near the Dandora dumpsite in Nairobi, Kenya, one of East Africa’s largest waste sites. That early exposure shaped her understanding of the plastic pollution crisis long before it became a global conversation.
She studied Materials Science at Jomo Kenyatta University of Agriculture and Technology and later worked as a data analyst and engineer.
In 2017, she left that stability with a conviction that plastic waste was not only a problem to complain about but a resource to build with.
She set up a small laboratory in her mother’s backyard and spent time experimenting with combinations of waste plastics and sand to create paving bricks.
She designed and built the necessary machinery herself. In 2018, she founded Gjenge Makers, which means “build yourself” in Swahili, and transitioned from the backyard setup into a production facility in Nairobi.
Gjenge Makers produces between 1,000 and 1,500 plastic-composite paving bricks daily, recycling around half a ton of plastic waste each day.
These bricks are stronger than traditional concrete and provide an affordable, sustainable building material. Since its inception, the company has recycled more than 200,000 kilograms of plastic waste. It employs around 250 people from marginalised communities in Nairobi and beyond.
The company sources plastic waste largely from packaging factories and local waste collectors and purchases from women and youth groups, creating both environmental and economic impact.
Despite high demand, with orders often exceeding production capacity, the focus remains on scaling responsibly and sustainably.
Nzambi Matee’s work has earned widespread recognition. In 2020, the United Nations Environment Programme named her a Young Champion of the Earth, the programme’s highest environmental honour for young people.
In 2021, she received the Prince William Award for Conservation in Africa. In 2022, she was named the UK Women of the Year Eco-Champion. Her work has been featured by major international media including BBC, CNN, and other global outlets.
She was also selected as a member of The Explorers Club 50, recognising the fifty most adventurous and impactful innovators and explorers shaping the world today.
Nzambi Matee’s journey shows that Africa’s most transformative companies are not always built in corporate boardrooms.
Sometimes they begin in a backyard with nothing but an engineering degree, a mountain of plastic waste, and the refusal to walk past a problem without solving it.
Image Credit: The Explorers Club
