Director, Developmental Association of Renewable Energies, Yahaya Ahmed, discusses with BIODUN BUSARI the feats and challenges of building houses with plastic bottles in the country
What was your experience like building the first house with 14,800 sand-filled plastic bottles?
Well, at that time, it was even relatively easier to get the bottles because they were all scattered everywhere. The whole idea was that we had, on one side, boys who were idle and jobless, just begging on the streets. They were approached and convinced to pick bottles for us. In addition, I thought it worked well.
Where did you learn the technology?
I learnt the technology or the procedure in Germany from the German who invented it. So, we organised with some non-governmental organisations for him to come and train us here. When he trained us, we started gathering the bottles from gutters and farms. That was how we gradually went on to build the first one as a model.
From there, we trained some people, and a few people got interested. We began to get some contracts here and there to go and build. But as of now, because of recycling—which is a very good initiative for the country—the bottles have become valuable items. They are being gathered by almost everybody, especially scavengers.
However, not all bottles are recycled. Some are just thrown away when they can’t find buyers. Even now, if you buy them from the scavengers, it’s easier to get the supplies. Before, we had to take the pains of going everywhere to collect and put them together. But now you can just buy from different scavengers. It’s not very expensive, yet I think it’s still a valid alternative to the concrete building blocks.
How consistent have you been after the first building?
The first one was around 2012 or 2013. But we’ve been building. The last one we did was in March. It was a public toilet in a community school in Kaduna. The school didn’t have toilets, so we built a four-room toilet facility for them. It’s just in a community school in Kaduna.
How many bottles did it cost?
We used about 8,000 bottles. The project was organised by some Sociology students of Ahmadu Bello University. They managed the funding, and we just provided the workforce.
How do you get contracts?
Mostly, people call us to make enquiries, and then one of the questions would be how to build something like that. So, we have two options. First of all, get enough bottles. Depending on what the person wants to construct, we provide a rough estimate of bottles needed to build that.
The client provides the bottles either by purchasing or gathering. Then we take it from there. So, we agree on the price, and then we go and start filling the bottles with sand. Then, there is a mixture of laterite and sharp sand. It’s also compact.
The filling is the most difficult and time-consuming part because we do everything manually. After that, all the other fixings—doors, windows, and interiors—are put in place. We just build the raw structure. We get funding from organisations and people who need such projects.
Do the people work with you after the training?
No, not necessarily, because we can’t employ them. After training them, whenever there’s a demand, we try to look for who is available. We call them when there is a project. Meanwhile, they also look for the projects on their own. But we can’t really train and then retain or employ them.
Is there support from the government or its agencies?
There is no support from the government, whether state or local governments, whereas people outside the country value our projects. The government doesn’t value it so much because they don’t see it as a viable solution.
A particular deputy governor who later became governor once told me bluntly that the idea was not sustainable, and I told him that we had waste everywhere where bottles could be picked, especially in Kaduna, which makes it sustainable and efficient. I tried to convince him to see the reasons why plastic bottles should be used for buildings, but he didn’t buy into the idea.
When it rains a little bit, like 30 minutes, you see that the whole half of the city is flooded. It is because of this poor drainage system filled to the brim with plastic bottles. The organic waste can be carried by the water, but bottles don’t decay. They just clog up the system. So, most of what we do is with private people and private organisations.
How many people have you trained altogether since the inception of your organisation?
We train people in groups. We have trained a group of 50 people. We’ve had this group about four times. We don’t take more than 50 at a time. We also do interlocking tiles. We also use soft plastic that is used in packaging bread—nylon bags. We use them in making interlocking tiles.
When we have people or organisations as sponsors, more people can be trained. There was a time when we got an invitation from Ogun State, which sent 10 people to us for training in one of the projects. They came to stay with us in Kaduna for about eight weeks.
How many houses have you built with this plastic bottle initiative?
We have constructed up to 15 houses. We built some in Kano and also in Kaduna. In Kaduna, we have three now. We have the first house we built, the public toilet, and another small facility. But we also built a complete house in Ibadan. It was a complete three-bedroom house, which is now being used as an office and a living room.
Then in Abuja, we built a five-bedroom duplex. It’s not only a small bungalow that can be built with it; storey-buildings can be built. We also built in Port Harcourt and other major places in the country. Outside Nigeria, a traditional ruler in Ghana saw our projects on YouTube and invited us for training.
We spent about four and a half months training his people in one village near Kumasi. We trained about 15 people. After the training, we built some structures there for them to learn. I think they are building a palace there and also using the plastic bottles to do the fencing. So, this is how it is evolving.
What are the benefits of these plastic bottles?
The benefits are many. First of all, you have to look at the financial cost. It is cheaper compared to concrete or clay buildings. It’s at least half of the cost of building a house with sand or clay—or even less—depending on the collection of bottles. If the sand we dig from the foundation is good enough, we use it to fill the bottles, and we also use it as a binding material.
If it is clay enough, we use it, and if not, we have to buy laterite to mix with it. So we don’t throw anything away. Normally, builders don’t use the sand or clay dug from the foundation in building; they throw it away. But we don’t do that. We take that sand, cut it, put it aside, and sieve it. We remove the big stones and use them to fill the bottles.
When do you start using cement?
We don’t use any cement except for the foundation itself, depending on the type of soil. We do it just to reinforce the foundation. We do a layer about 5 or 10 centimetres, depending on the soil, and then a concrete layer. That starts with the foundation, with the bottles. But from there, we don’t use cement again until we finish everything. We use it in plastering.
If we leave it like that, it looks even more beautiful, but we have to plaster it because of the rain. Apart from that, the second advantage is the contribution to the environment. You clean the environment. We use bottles to build. It’s not even recycling—it’s upcycling.
In some recycling processes, the bottles can be turned into something else, but they become waste again and go back into the waste dump. Recycling will come back into the system. If you cannot recycle it again, it goes into the waste dump. But this one is upcycling—it doesn’t come back again. Another advantage is that it is more durable than cement blocks.
How long can the sand-filled plastic bottle buildings last?
With plastic bottle buildings, if you come back in 200 or 250 years, you’ll still see them there. If there’s no bomb or explosive to destroy it, you’ll still meet it in 250 years. And it’s climate-regulated. Especially in the North, during harmattan, it’s cold outside, but if you come in, it’s very warm.
Then, during the hot seasons, it’s very hot—almost 40 degrees outside. But if you come in, it’s cool—just less than 26 degrees, or 26 degrees at most. So, you don’t even need an air conditioner. If you really need more cooling, a ceiling fan or a standing fan will do.
It is also bulletproof. If you shoot at sandcrete blocks with an AK-47, it will penetrate. But it won’t penetrate sand-filled plastic bottles, unless you use bombs. It’s just like the roadblocks the military uses—they put sand.
What have been your challenges since you started?
The first challenge is the difficulty in getting support from the authorities. Also, getting permits to build in some places is a challenge. In some places, they don’t understand the concept, so they wouldn’t even agree on the permits.
Another challenge is awareness—how to let people know that their mud houses should be replaced in the villages with sand-filled plastic bottles. We also don’t have funding. Mud houses collapse during rainy seasons. It’s a multi-faceted challenge—from the authorities to the local people.
Are there rivalries from sandcrete or block construction stakeholders?
Well, for now, it is not so widespread. That’s why some of them have not come up with much rivalry. Maybe there could be at a later stage, but as of now, it hasn’t got to that stage where people are competing with us. But some people made remarks some time ago that we were trying to de-market sandcrete buildings, but we just laughed about it.
Where we get some real competition is in the area of interlocking. The sole reason is that our interlocking is cheaper and stronger than the cement-made ones. We’re already facing that.
