9 building materials made entirely from waste products

No doubt an architectural treasure trove. Image: Cezary p at Wikimedia Commons.

Building with Waste, a new book about, well, you can guess, may not sound like it should top your holiday reading list – but, construction geeks as we are, we found its premise fascinating. Every year, human settlements produce 1.3bn tonnes worth of solid waste products. The book argues that we could and should be putting this to good use as cheap, durable and green building materials. 


Compilers Dirk E. Hebel, Marta H. Wisniewska and Felix Heise looked into the worlds of architecture, construction, and the delightfully named field of "garbology" to find new and exciting materials made out of stuff you'd normally find at a landfill site. Their book argues that, in future, we could end up re-using pretty much everything, as we did back when all waste was organic.

This could come in handy if, as is predicted, our municipal waste output doubles by 2025. As Mitchell Joachim, one of the book's contributors, puts it:

The future city makes no distinction between waste and supply. 

So, from animal blood bricks to nappy roofing, here are our favourite waste-based materials featured in the book. 

1. NewspaperWood

Image: ViJ5.

This design comes froom Norway, where over 1m tonnes of paper and cardboard are recycled every year. The wood is created by rolling up paper and solvent-free glue to create something not dissimilar to a log, then chopping it into usable planks. The wood can then be sealed so it's waterproof and flame-retardant, and used to build anything you would normally build with wood. 

2. Nappy roofing

Image: Lightweight tiles ltd.

Good news: something can be salvaged from all those nappies and sanitary products we throw away, even though they're, well, really gross. Special recycling plants separate out the polymers from the, er, organic waste, and these polymers can then be used to ceate fibre-based construction materials like the tiles in the image above. 

3. Recy blocks

Image: Gert de Mulder. 

These colourful bricks are made from old plastic bags, which are notoriously difficult to recycle in any other way. Recycled bags or plastic packaging are placed in a heat mold, and forced together to form the blocks. They're too lightweight to act as load-bearing walls, but can be used to divide up rooms or outdoor areas. 

4. Blood Brick

Image: Jack Munro.

This idea rests on the assumption that animal blood counts as a waste product. This, we realise, is a potentially offensive idea – but while carnivores are still munching away, they're still wasting loads of animal blood, especially in societies without industrialised food production systems. And, as it turns out, blood is one of the strongest bio-adhesives out there, as it contains high levels of protein. 

British architecture student Jack Munro proposes using freeze-dried blood (which comes as a a powder), mixed with sand to form a paste; this can then be cast as bricks. This could be especially useful in remote communities, where blood from animal slaughter is plentiful, but strong construction materials are thin on the ground.

5. Bottle bricks 

Image: Aaron "tango" Tang via Flickr. 

This proposal is a little different, as it relies on producing a consumer good specifically so it can later be used as a building material. Lots of companies now make bottles in cuboid or other tesselative shapes, to make them easier to transport.

But the practice of doing so to create construction materials actually started with beer company Heineken in the 1960s – Alfred Henry Heineken, owner of the brewery, visited a Carribean island and was dismayed at both lack of shelter, and the number of discarded Heineken bottles scattered everywhere. So the company landed on a new, brick-shaped design for the bottle, shown in the images above. The bottleneck slots into the base of the next bottle, forming an interlocking line. 

6. Smog insulators

Image: New Terrirories/City of Bangkok.

One of our biggest waste receptacles is the air, which isn't great for our lungs, or for the human race's chances of survival on a planet that's rapidly getting hotter. "Dustyrelief", a system created by the City of Bangkok and design firm New-Territories, involves placing an electrically charged metal mesh over a building, which attracts large smog particles and sticks them together. Eventually, this creates a kind of silvery fur over the building's surface. Not particularly attractive, perhaps, but much better than a similar shag forming on the insides of your lungs.

7. Mushroom walls

Image: Evocative designs.

Here, designers figured out a way to grow wall insulator and packing materials using mycelium, a bacteria found in rotting organisms like tree trunks and agricultural byproducts. If placed in a mold, these organic matters grow to the desired shape within a couple of days, and can then be stopped using a hot oven. This is particularly useful because traditional insulating and packing materials tend to be non-biodegradable, or, in the case of asbestos, poisonous.

8. Plasphalt 

The bit on the left is plasphalt, the bit on the right is asphalt. Image: TEWA.

OK, yes, we mostly like this one for its fun name. Plasphalt is made up of grains of plastic produced from unsorted plastic waste, which replaces the sand and gravel traditionally used in asphalt production. In testing, it was found that plasphalt roads were far less vulnerable to wear and tear than traditional asphalt, because the asphalt emulsion bonded better with the plastic than with gravel or sand.

9. Wine cork panels

Image: Yemm & Hart materials.

These wall or floor tiles are made by combining recycled granulated cork with whole wine corks, which you can see as those oblong shapes in the tiles above. This is a pretty useful idea, considering the world apparently consumes around 31.7bn bottles of wine a year. For shame.

 
 
 
 

What Citymapper’s business plan tells us about the future of Smart Cities

Some buses. Image: David Howard/Wikimedia Commons.

In late September, transport planning app Citymapper announced that it had accumulated £22m in losses, nearly doubling its total loss since the start of 2019. 

Like Uber and Lyft, Citymapper survives on investment funding rounds, hoping to stay around long enough to secure a monopoly. Since the start of 2019, the firm’s main tool for establishing that monopoly has been the “Citymapper Pass”, an attempt to undercut Transport for London’s Oyster Card. 

The Pass was teased early in the year and then rolled out in the spring, promising unlimited travel in zones 1-2 for £31 a week – cheaper than the TfL rate of £35.10. In effect, that means Citymapper itself is paying the difference for users to ride in zones 1-2. The firm is basically subsidising its customers’ travel on TfL in the hopes of getting people hooked on its app. 

So what's the company’s gameplan? After a painful, two-year long attempt at a joint minibus and taxi service – known variously as Smartbus, SmartRide, and Ride – Citymapper killed off its plans at a bus fleet in July. Instead of brick and mortar, it’s taken a gamble on their mobile mapping service with Pass. It operates as a subscription-based prepaid mobile wallet, which is used in the app (or as a contactless card) and operates as a financial service through MasterCard. Crucially, the service offers fully integrated, unlimited travel, which gives the company vital information about how people are actually moving and travelling in the city.

“What Citymapper is doing is offering a door-to-door view of commuter journeys,” says King’s College London lecturer Jonathan Reades, who researches smart cities and the Oyster card. 

TfL can only glean so much data from your taps in and out, a fact which has been frustrating for smart city researchers studying transit data, as well as companies trying to make use of that data. “Neither Uber nor TfL know what you do once you leave their system. But Citymapper does, because it’s not tied to any one system and – because of geolocation and your search – it knows your real origin and destination.” 

In other words, linking ticketing directly with a mapping service means the company can get data not only about where riders hop on and off the tube, but also how they're planning their route, whether they follow that plan, and what their final destination is. The app is paying to discount users’ fares in order to gain more data.

Door-to-door destinations gives a lot more detailed information about a rider’s profile as well: “Citymapper can see that you’re also looking at high-profile restaurant as destinations, live in an address on a swanky street in Hammersmith, and regularly travel to the City.” Citymapper can gain insights into what kind of people are travelling, where they hang out, and how they cluster in transit systems. 

And on top of finding out data about how users move in a city, Citymapper is also gaining financial data about users through ticketing, which reflects a wider trend of tech companies entering into the financial services market – like Apple’s recent foray into the credit card business with Apple Card. Citymapper is willing to take a massive hit because the data related to how people actually travel, and how they spend their money, can do a lot more for them than help the company run a minibus service: by financialising its mapping service, it’s getting actual ticketing data that Google Maps doesn’t have, while simultaneously helping to build a routing platform that users never really have to leave


The integrated transit app, complete with ticket data, lets Citymapper get a sense of flows and transit corridors. As the Guardian points out, this gives Citymapper a lot of leverage to negotiate with smaller transit providers – scooter services, for example – who want to partner with it down the line. 

“You can start to look at ‘up-sell’ and ‘cross-sell’ opportunities,” explain Reades. “If they see that a particular journey or modal mix is attractive then they are in a position to act on that with their various mobility offerings or to sell that knowledge to others. 

“They might sell locational insights to retailers or network operators,” he goes on. “If you put a scooter bay here then we think that will be well-used since our data indicates X; or if you put a store here then you’ll be capturing more of that desirable scooter demographic.” With the rise of electric rideables, Citymapper can position itself as a platform operator that holds the key to user data – acting a lot like TfL, but for startup scooter companies and car-sharing companies.

The app’s origins tell us a lot about the direction of its monetisation strategy. Originally conceived as “Busmapper”, the app used publicly available transit data as the base for its own datasets, privileging transit data over Google Maps’ focus on walking and driving.  From there it was able to hone in on user data and extract that information to build a more efficient picture of the transit system. By collecting more data, it has better grounds for selling that for urban planning purposes, whether to government or elsewhere.

This kind of data-centred planning is what makes smart cities possible. It’s only become appealing to civic governments, Reades explains, since civic government has become more constrained by funding. “The reason its gaining traction with policy-makers is because the constraints of austerity mean that they’re trying to do more with less. They use data to measure more efficient services.”  

The question now is whether Citymapper’s plan to lure riders away from the Oyster card will be successful in the long term. Consolidated routing and ticketing data is likely only the first step. It may be too early to tell how it will affect public agencies like TfL – but right now Citymapper is establishing itself as a ticketing service - gaining valuable urban data, financialising its app, and running up those losses in the process.

When approached for comment, Citymapper claimed that Pass is not losing money but that it is a “growth startup which is developing its revenue streams”. The company stated that they have never sold data, but “regularly engage with transport authorities around the world to help improve open data and their systems”

Josh Gabert-Doyon tweets as @JoshGD.