Kenya recycles plastic bottles into bricks stronger than concrete
A 29-year-old Kenyan entrepreneur has created blocks out of waste plastic and sand that she claims are stronger, cheaper and more durable than concrete.
Nzambi Matee, a materials science graduate who got a scholarship to study the innovative admixture in the US, set up her slab-making workshop in her mother's back garden in Nairobi, and can produce 1,500 a day.
Her company, Gjenge Makers, has sold slabs to local schools and homeowners.
[edit] Flow-up update 2023
Gjenge is a community-oriented organization whose aim is to address the need for sustainable and affordable alternative construction materials in Kenya and the Continent. Our initial output is innovations derived from recycled plastics to produce paving blocks, paving tiles, and manhole covers.
Our team ideated a rollout of a plastics collection company that would sort and sell plastic waste to other recycling companies. Having collected more waste faster than the recycling companies could uptake, this original idea was pivoted, and a decision was made to do value addition to these plastics hence the decision to manufacture alternative building products emerged. Thus, Gjenge Makers was born.
Our mission is to innovate solutions to create beautiful and sustainable alternative construction products for Kenya and the African continent with the aim of providing sustainable and affordable alternative building materials whilst creating job opportunities for youths and women by promoting recycling and upcycling culture in Kenya and Africa.
We collect waste plastics and process it using the latest cutting-edge technologies to mix the recycled plastic with sand to form a mixture which we mold into our various products.
Gjenge Makers has cut a niche as a manufacturing trailblazer in the provision of beautiful and sustainable alternative building materials.
For further information visit https://www.gjenge.co.ke/about
[edit] Original GCR article 2021
The UN Environment Programme's (UNEP) named her 2020's Young Champion of the Earth in Africa.
Surprisingly, the plastic slabs are up to five times heavier than concrete ones owing to the lack of air pockets, but she says they are more flexible, durable and have a higher melting point.
The plastic pavers are 30% cheaper than traditional concrete ones, come in different colours and are certified by the Kenya Bureau of Standards.
Gjenge Makers offers three types of slabs: a light option for footpaths, a mid-tier paver for commercial projects and a heavy duty alternative for roads.
Matee has a material science degree and previously worked in Kenya's oil industry as an engineer, but quit to found Gjenge Makers. She obtained a scholarship to the University of Colorado Boulder to work on the ratios of sand to plastic in Gjenge Makers' bricks.
Nzambi Matee said to the UNEP: "Plastic is a material that is misused and misunderstood. The potential is enormous, but it's after life can be disastrous."
This article originally appeared on Global Construction Review. Images courtesy of Gjenge Makers. Republished on the CIAT news and blog site as "Kenyan start up recycles plastic bottles into bricks stronger than concrete" dated February 15 2021.
--CIAT
[edit] Related articles on Designing Buildings.
- Glass reinforced plastic GRP.
- Glass fibre reinforced plastic.
- Polycarbonate plastic.
- Plastic cladding.
- Plastic and recycling.
- Plastic coating market.
- Plastic in construction.
- Plastic in concrete.
- Recycled plastic bridges.
- Recycled waste plastic in construction.
- The K-briq a circular product.
- Types of plastic in construction.
- Wood plastic composites market for construction.
Featured articles and news
Key points for construction at a glance with industry reactions.
Functionality, visibility and sustainability
The simpler approach to specification.
Architects, architecture, buildings, and inspiration in film
The close ties between makers and the movies, with our long list of suggested viewing.
SELECT three-point plan for action issued to MSPs
Call for Scottish regulation, green skills and recognition of electrotechnical industry as part of a manifesto for Scottish Parliamentary elections.
UCEM becomes the University of the Built Environment
Major milestone in its 106-year history, follows recent merger with London School of Architecture (LSE).
Professional practical experience for Architects in training
The long process to transform the nature of education and professional practical experience in the Architecture profession following recent reports.
A people-first approach to retrofit
Moving away from the destructive paradigm of fabric-first.
International Electrician Day, 10 June 2025
Celebrating the role of electrical engineers from André-Marie Amperè, today and for the future.
New guide for clients launched at Houses of Parliament
'There has never been a more important time for clients to step up and ...ask the right questions'
The impact of recycled slate tiles
Innovation across the decades.
EPC changes for existing buildings
Changes and their context as the new RdSAP methodology comes into use from 15 June.
Skills England publishes Sector skills needs assessments
Priority areas relating to the built environment highlighted and described in brief.
BSRIA HVAC Market Watch - May 2025 Edition
Heat Pump Market Outlook: Policy, Performance & Refrigerant Trends for 2025–2028.
Committing to EDI in construction with CIOB
Built Environment professional bodies deepen commitment to EDI with two new signatories: CIAT and CICES.
Government Grenfell progress report at a glance
Line by line recomendation overview, with links to more details.
An engaging and lively review of his professional life.
Sustainable heating for listed buildings
A problem that needs to be approached intelligently.
50th Golden anniversary ECA Edmundson apprentice award
Deadline for entries has been extended to Friday 27 June, so don't miss out!
CIAT at the London Festival of Architecture
Designing for Everyone: Breaking Barriers in Inclusive Architecture.
Mixed reactions to apprenticeship and skills reform 2025
A 'welcome shift' for some and a 'backwards step' for others.
Comments
[edit] To make a comment about this article, or to suggest changes, click 'Add a comment' above. Separate your comments from any existing comments by inserting a horizontal line.