Skip to content

You are using an outdated browser

Internet Explorer is not supported by this site and Microsfot has stopped releasing updates, therefore you may encounter issues whilst visiting this site and we strongly recommend that you upgrade your browser for modern web functionality, a better user experience and improved security.

Upgrade my browser

Building a greener Nairobi, block by block

5 min read

Good Stuff
Building a greener Nairobi, block by block
Source: Facebook/NzambiMatee

UN Environment Program ‘Young Champions of the Earth’ prize winner Nzambi Matee is a 29-year-old inventor and social entrepreneur who has so far turned 20 tons of plastic trash into durable and affordable paving bricks.

Meet the engineer who turns plastic trash into paving stones

Social entrepreneur Nzambi Matee (29) is a materials engineer and head of Gjenge Makers Ltd, a sustainable, alternative and affordable, building products manufacturing company, which produces low-cost construction materials made from recycled plastic waste and sand.

She set up a small lab in her mother’s back yard and began creating and testing pavers, which are a combination of plastic and sand.
Matee was inspired to launch her business after routinely coming across plastic bags strewn along Nairobi’s streets. She set up a small lab in her mother’s back yard and began creating and testing pavers, which are a combination of plastic and sand. Source: Facebook/NzambiMatee

Building blocks for a greener Nairobi

United Nations Environment Programme’s (UNEP) Young Champions of the Earth prizewinner Nzambi Matee’s small workshop in Nairobi, Kenya is chock-a-block with metal pipes and machine cogs. It may seem chaotic to outsiders but the 29-year-old Matee, an inventor and entrepreneur, is at home here. This is where she developed the prototype for a machine that turns discarded plastic into paving stones – an invention that underpins her company, Gjenge Makers.

Each day, the business churns out 1,500 plastic pavers, which are prized by schools and homeowners because they are both durable and affordable. Gjenge Makers is also giving a second life to plastic bottles and other containers which would otherwise end up in landfills or, worse, on Nairobi’s streets.

“It is absurd that we still have this problem of providing decent shelter – a basic human need,” said Matee.“Plastic is a material that is misused and misunderstood. The potential is enormous, but its after life can be disastrous.”

Source: UNEP

This is amalgamated with discarded single use plastics that informal waste collectors deliver to them, which they jointly use to produce the pavers, while providing the waste collectors with a stable income.
Gjenge Makers have partnered with different manufacturers of plastics bottle tops and seals in the beverage and pharmaceutical industries in Kenya, from whom they collect offcuts and scraps. This is amalgamated with discarded single use plastics that informal waste collectors deliver to them, which they jointly use to produce the pavers, while providing the waste collectors with a stable income. Source: Photo: UNEP

Gjenge pavers: closing the loop towards a circular economy

For her work, Matee was recently named a Young Champion of the Earth by the United Nations Environment Programme (UNEP). The award provides seed funding and mentorship to promising environmentalists as they tackle the world’s most pressing challenges.

“We must rethink how we manufacture industrial products and deal with them at the end of their useful life,” said Soraya Smaoun, who specialises in industrial production techniques with UNEP.  “Nzambi Matee’s innovation in the construction sector highlights the economic and environmental opportunities when we move from a linear economy, where products, once used, are discarded, to a circular one, where products and materials continue in the system for as long as possible.” 

They have a melting point over 350°C, and they are much stronger than their concrete equivalents.
Gjenge pavers are fully certified by the Kenyan Bureau of Standards. They have a melting point over 350°C, and they are much stronger than their concrete equivalents. Source: Gjenge.co.ke

The heavy toll of plastic

The world is awash in plastic. Globally, 1 million plastic drinking bottles are purchased every minute while up to 5 trillion single-use plastic bags are used annually.

Matee, who majored in material science and worked as an engineer in Kenya’s oil industry, was inspired to launch her business after routinely coming across plastic bags strewn along Nairobi’s streets.

In 2017, Matee quit her job as a data analyst and set up a small lab in her mother’s back yard. There, she began creating and testing pavers, which are a combination of plastic and sand. The neighbours complained about the noisy machine she was using, so Matee pleaded for one year’s grace to develop the right ratios for her paving bricks.

“I shut down my social life for a year, and put all my savings into this,” she said. “My friends were worried.”

Through trial and error, she and her team learned that some plastics bind together better than others. Her project was given a boost when Matee won a scholarship to attend a social entrepreneurship training programme in the United States of America. With her paver samples packed in her luggage, she used the material labs in the University of Colorado Boulder to further test and refine the ratios of sand to plastic.

Matee also used this opportunity to develop the machinery she would use to make the bricks. “Once we know how to make one paver, we need to know how to make 1,000 pavers,” she explained.

Source: UNEP

The 29-year-old’s mission is to innovate solutions to create beautiful and sustainable alternative construction products for Kenya and the African continent, whilst creating job opportunities for youths and women, and promote a recycling and upcycling culture.
Matee is a self-driven individual, serial entrepreneur and a self-taught hardware designer and mechanical engineer with a background in physics and material engineering. The 29-year-old’s mission is to innovate solutions to create beautiful and sustainable alternative construction products for Kenya and the African continent, whilst creating job opportunities for youths and women, and promote a recycling and upcycling culture. Source: Facebook/NzambiMatee

Reaching the finish line

Matee recalls the first time she produced a full batch of recycled plastic pavers. “It was the best day ever!” she exclaimed. “This was three years of hard work. I quit my job. I put all my savings into this. I became so broke that everyone thought I was crazy and so many people told me to give up.”

One of the schools that uses pavers is the Mukuru Skills Training Centre in Nairobi’s Mukuru Kyaba slum. Its playground and the paths between classrooms are covered by Matee’s colourful paving stones. (Before the pavers, students walked on dirt paths.)

“We plan to pave all around the school,” said programme coordinator Anne Muthoni. “It’s a cheaper solution and we are grateful to Nzambi. Young people need to be motivated and sensitized about how to care for the environment, while at the same time making money.”

Matee encourages other young people to tackle environmental challenges at the local level. “The negative impact we are having on the environment is huge,” said Matee. “It’s up to us to make this reality better. Start with whatever local solution you can find and be consistent with it. The results will be amazing.”

Source: UNEP

Nzambi Matee - Young Champion of the Earth 2020 “I’m acting for nature…by turning plastic pollution into a building solution.”
Nzambi Matee of Gjenge Makers Ltd is a Young Champion of the Earth: http://bit.ly/3gMPrgR
#YoungChamps #ForNature Source: Facebook/UNEP

About The United Nations Environment Programme’s Young Champions of the Earth prize

The United Nations Environment Programme’s Champions of the Earth and the Young Champions of the Earth honour individuals, groups and organizations whose actions have had a transformative impact on the environment.

The Young Champions of the Earth prize is the United Nations Environment Programme’s leading initiative to engage youth in tackling the world’s most pressing environmental challenges. Nzambi Matee is one of seven winners announced in December 2020, on the cusp of the UN Decade on Ecosystem Restoration 2021-2030.

By showcasing news of the significant work being done on the environmental frontlines these awards aim to inspire and motivate more people to act for nature. Both awards are part of UNEP’s #ForNature campaign to rally momentum for the UN Biodiversity Conference (COP 15) in Kunming in May 2021, and catalyze climate action all the way to the UN Climate Change Conference (COP26) in Glasgow in November 2021.  

Make an Impact

9 REASONS TO REFUSE SINGLE-USE PLASTIC + 9 TIPS FOR LIVING WITH LESS OF IT

Single use plastic is everywhere. In a matter of decades we have become addicted to the convenience of single use plastic. But we cannot escape the consequences of throwing away vast quantities of a material that takes hundreds of years to break down. Here are 9 reason why we should refuse it, and 9 ways to be less reliant on it.