Bone Cities, Ash Towers, and 4 Other Futuristic Buildings

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to learn more. [♪ INTRO] Right now, the construction industry heavily
relies on concrete. And for some good reasons. Concrete is cheap, and it is a highly efficient
way to build safe and secure buildings. But it’s also so bad for the Earth. It takes huge amounts of energy to produce
and ship this stuff, and these days, concrete alone produces about 8%
of global carbon emissions. In 2018, that translated to almost 3 billion
metric tons of carbon dioxide. So while concrete is convenient and all, it
would be great if we could find an alternative and start making our buildings out of something else. Well, maybe shockingly, we’re not actually
the first people to have had this thought! Many scientists are already conducting research
into the materials of the future, and some of their ideas are so off the wall that they
just might work. Here are six of them. Let’s kick things off with one of the weirder
examples: synthetic bone. Because, you know. Living in a building made
of real bones, that would just be too upsetting. Scientists at Cambridge have been working
on this project since around 2011, and although it may seem odd, there are several good reasons for using bone-like materials in construction. For one, bones are incredibly strong for their
size and weight. A bone fragment the size of a sugar cube can
support over 1500 kilograms, more than some types of concrete. Also, thanks to their structure and composition, bones are very elastic and resistant
to fracture and breaking. They’re made of minerals like calcium and
phosphate, along with the protein collagen. That collagen clusters into long fibers, and
it combines with the mineral in just the right way to create a strong, flexible matrix. Your body made this kind of matrix over years
of development, but to make synthetic bones, scientists have found ways to speed up that
process. To make their material, they dip a small template
into a solution of calcium and collagen proteins. Then, they dip that into a solution of phosphate
and collagen proteins. And back again. This process is repeated over and over,
layer after layer, until it creates a sample that mimics the strength and structure of natural bone. This method is great, and if we could get
it going on a large scale, it seems like it could be a cool alternative to concrete. But it does have its downsides. Right now, the biggest problem is that the
only good place to get collagen is from animals. This protein is super hard to replicate in
the lab, so if we wanted to build something from synthetic bone, we would need a lot of animal parts. And while we could use waste from the meat
industry, even that might not be enough. So until we figure out synthetic collage, don’t expect to see super goth, bone cities any time soon. But, that doesn’t mean they’re off the
table. So I want to see it in your scifi short stories! Next, the magic of mushrooms is at it again. While some teams are looking for materials
that outperform concrete, others are just looking for things
that are safe for the environment. And that’s led them down some weird paths. Take the work of an architectural team known
as The Living. In 2014, they designed and built a 12 meter-tall
castle, the first and only building to be made of nothing but fungi. The bricks in this tower were made of recycled
mycelium, which are thin, branching structures
that look similar to roots. The mycelium was collected from fungi that
grew on agricultural waste, like corn and wheat crops, so it was a totally sustainable
and renewable material. And the bricks weren’t that hard to make, either. To create them, researchers placed organic
materials, anything from dirt to nut shells, full of mushroom spores into a brick mold. And in only 5 days, the mycelium had grown
dense enough to make a brick. As a bonus, because these blocks are made
from fungi, they’re totally compostable. If you throw them in a compost heap, they
would be dirt again within sixty days. Still, just because these bricks are eco-friendly
doesn’t mean they’re strong. They can withstand only about 0.2 megapascals
of pressure, which is less than 1% of what concrete can handle. Realistically, that means we will not be building
mycelium cities. Instead, researchers have suggested that we
could combine the mycelium with other things to make more stable structures. So, it’s a start! Both synthetic bone and mycelium are pretty
futuristic materials, and it’s going to take a lot of work to figure out how they
might fit into our world. But this next example might be pretty easy
to adopt. In 2013, scientists at MIT developed 3-D-printed,
reusable bricks that function a lot like LEGO bricks. Except, instead of being made of regular plastic,
they’re made from a carbon-reinforced epoxy resin. Epoxy resins are a group of materials that
easily form strong bonds with other materials, like glass or carbon. They’re exceptionally strong and very resistant
to erosion or damage. And in this case, since they’re being 3-D
printed, they’re customizable, too. Engineers can make structures stronger or more elastic by assembling the resin bricks into different shapes. Now, to be clear, most epoxy resins aren’t
that environmentally friendly. They’re basically a type of plastic, and
plastic is, you know, terrible for the environment. It requires a lot of natural resources to
make and takes forever to disintegrate. But these bricks try to make up for that by
being extremely reusable. They’re easy to retrieve when a building
needs to be taken down, and they can be used again and again for new buildings. Also, these things are surprisingly strong. Structures made from them can withstand 12.3
megapascals of pressure, which is incredible for such small and light materials. For comparison, average concrete can withstand
17 to 28 megapascals of pressure. And it’s much heavier and worse for the
planet. Researchers believe these blocks might not
be strong enough for skyscrapers, but they could be used in much smaller buildings, like
houses. And it’s not hard to imagine a future where
a crew shows up, stacks a bunch of blocks together, and creates the shell of a house. So again, if these bricks can be mass-produced,
it could mean great things for construction. The last 3 examples have been pretty innovative, but they’ve almost entirely ditched traditional building materials and gone in new directions. That’s great, because new ideas can lead
to big places. But it also means that it might be a while
before these things hit the primetime. These next examples, though, are a bit different: They’re more practical, and probably wouldn’t
be as expensive to implement on a larger scale. So you might be seeing them enter the market
a bit sooner. One option like this is called AshCrete, and
it’s a modified version of concrete. Standard concrete is made by using cement
to bind together small aggregates like sand, gravel, or crushed stone. This makes it heavy and hard to transport,
but also, those aggregates aren’t sustainable. We only have so much sand and stone to throw
around. Enter AshCrete. It’s an alternative concrete made using ash from waste-incineration facilities as the aggregate particles. It can be used in many of the same places
as traditional concrete, and it allows those waste facilities to recycle some of their ash. So, win-win. Unfortunately, although it can solve some
of concrete’s problems, it’s not perfect. Most notably, making and transporting AshCrete
requires the same amount of energy as concrete, and this new material isn’t great for all
climates. Compared to regular concrete, AshCrete can
take longer to solidify, and it’s more susceptible to cracking from freeze/thaw cycles, since it doesn’t trap as many insulating air particles. So it has its flaws. But if we want to start rolling out better
materials for the planet soon, it might be a good place to begin. And besides Ashcrete, there’s also a number of other materials that try and improve upon things we have now. For instance, scientists have also thought
about trying to reinforce clay bricks with 2 of the most renewable substances we’ve
got: wool and seaweed. Which sounds weird, but would work surprisingly
well. Although they don’t get as much attention
as concrete, regular clay bricks are a huge pollution problem because they require a ton of energy and natural resources to make. Like, not only do you need things like soil,
sawdust, sand, and lime to make the brick, but then you have to fire it. And that means you have to burn things like
wood or coal, and that results in a bunch of carbon emissions. One way companies try and clean up this process
is by making what’s called a non-fired brick, where you use machines to smash a bunch of
clay together and then let it dry in the sun. The problem here is that the final product
typically isn’t as durable as a fired brick, but there might be a way to change that. At least, according to a 2010 paper published
in the journal Construction and Building Materials. In that paper, two architects suggested using
wool and seaweed to make these bricks even stronger. In these blocks, wool fibers are mixed with
a natural compound from seaweed called alginate. Then, that’s mixed into traditional, non-fired
clay bricks. The alginate acts as a binder instead of sawdust, and the wool fibers increase the strength and structure of the bricks. By a lot, actually! Traditional non-fired bricks have an average
strength of around 2.3 megapascals. But in a test, scientists demonstrated that
when both alginate and wool are added to the blocks, the strength increased to around 4.4
megapascal, almost double! That would make them great for things like
walls, small houses, or decorating. And with much less of an impact on the planet. Finally, our last and most practical example! Because, look, sometimes the future starts
small, and that’s okay. Say hello to the pollution-absorbing brick. These bricks were developed in 2013, and admittedly,
they are made of traditional concrete, since that allows them to be competitive with current
materials. But they’re trying really hard to make up
for that. These blocks take in pollution from the outside
air, and then release clean air into your building through a traditional ventilation system. So these things have two main components. The first is, of course, the brick itself,
which faces the exterior of the building. Each brick has a cyclone air filtration system
in it, which creates a super fast spiral vortex inside the brick, sort of like a mini hurricane or a centrifuge. As the vortex spins, the heavy pollutant particles
drop to the bottom of the vortex and are deposited into a collection hopper at the bottom of the wall. The second component is the recycled plastic
couplers, which go between each of the bricks. These couplers both help align the bricks and allow air to get into the center of the bricks and the filtration system. The blocks can trap about 30% of pollutants
from the air the touch, as well as 100% of coarse particles like dust. This makes them a great potential way to passively
clean up the air in our cities. So even though it won’t solve our concrete
problem, it is a start. And it could likely help us with at least
some of our environmental woes. There’s a ton of cool research being done
into alternative construction methods, and the list goes way beyond these six examples. That’s important to keep in mind, because
any one of these solutions probably can’t make construction eco-friendly all by itself. We’re likely going to need tons of alternative
options, so the more ideas there are, the better we might be. And things seem to be moving in the right
direction, at least, based on these projects. And one way or another, it’s cool to see
what kinds of solutions engineers are coming up with. Even if I never get to live in like, a sweet
bone building. If you enjoyed this episode of SciShow, there’s
another video series you might like. It’s called Digits, and you can find it
on CuriosityStream. CuriosityStream is a subscription-based streaming
service, and they offer more than 2400 documentaries from filmmakers all over the world. Digits is a series about the physical heart
of the Internet, and it has a really futuristic vibe, kind of like this episode of SciShow. It’s hosted by Veritasium’s Derek Muller,
and it talks about how the Internet got here and where it’s headed. If you want to give it a watch, you can get
31 days of CuriosityStream completely for free if you sign up at
and use the promo code “scishow.” After that, you can get unlimited access for
just $2.99 per month. When you sign up for CuriosityStream,
you’re also supporting SciShow and helping us make more content like this. So thanks for considering it. And we hope you learn something cool. [♪ OUTRO]

100 thoughts on “Bone Cities, Ash Towers, and 4 Other Futuristic Buildings”

  1. Maybe they can genetically modify a bacterium to produce and excrete collagen. That's the way a lot of proteins are mass-produced.

  2. Unfired clay bricks made from wool and seaweed? Pharaoh is interested in this. Oh wait, Pharaoh didn’t build from adobe, that was Sumerians.

  3. Scishow: *Shows crazy looking building animation in thumbnail*
    Also Scishow: **doesn't talk about crazy building at all**
    Sigh, Scishow: *Plugs in clip of crazy building during closing statements*

    Me: 😑

  4. Could always just make single family dwellings subterranean instead. Usually the ground is pretty solid and doesn't require significant reinforcing. Being flesh with the Earth, wind mostly ignores it. Because the ground is insulated, it stays the same temperature year round. Your biggest problems are earthquakes, infestation and flooding, but regular houses deal with that anyway. Infrastructure alterations are also a bit more challenging, but not impossible.

  5. That's it, I'm donating my collagen so I can have a bone statue made on my grave after the collagen extraction is complete.

  6. The carbon blocks… can we use the carbon in the atmosphere as direct supply of carbon to build those carbon blocks mentioned?

    Cause those blocks need carbon… so why not put the carbon in the air to work for us aka directly solving global warming concerns that way??

    There’s a white anionic resin material developed at Arizona state university that can directly harness carbon from the air. So…. can we combine these two technologies somehow??

    Go on. Look it up.

  7. I have a great Idea "Timber Buildings" as the tree grows it takes in carbon from the air OMG what a revolutionary idea. If we plant a huge number of tress in, i don't know tree farms it would almost be sustainable.

  8. Very cool, let's say these take off what can we do with the prexisting concrete? Be a shame let it go to waste as it breaks down.

  9. So these environmentally friendly and sustainable options are perfectly fine for homes but not good for skyscrapers.
    Hmmm sounds like we just dont need to be building any more skyscrapers…

  10. Wouldn't it make sense to combine Styrofoam with the ash in AshCrete? You would recycle waste Styrofoam AND make the concrete lighter and better insulating.

  11. Concrete is good more co2 means more plant growth, !!!!!! , this is why a greenhouse ad C02 to get more yield, concrete can be mix with any material, you cant with Calcium it becomes brittle with UV light
    ash Crete is from the Romans. Roman concrete is a mix of concrete and wood ash is not another class

  12. It's people. Concrete Green is made out of people. They're making our buildings out of people. Next thing, they'll be breeding us like cattle for food.

  13. i cant help it. 3:53 : they put organic material and fungal spores into a brick mold, and when the process is complete they pull out…. a mold brick

  14. What if they use all different types in a building, depending on their strengths, kind of like how we have roofs that have different types material on them, why not layer them, this way you could efficiently use different types instead of just using all of one. Pretty sure they've thought of this though.

  15. and if in every step of the production and ship of concrete used non-conbustion machines is it still gonna create carbon emission??

  16. I'm actually writing a scifi novel that takes place on a planet that was terraformed. Because pf this, there are some recourse options that aren't available on the planet. I've been working out the makeup of their location. Mainly what is made in what area. And I realized I need some substitutes. An alternative to plastic, concrete and wood. If anyone would be interested in kind of picking through the issues and helping me work out my options, that would be a huge help. They don't have to be presently viable. It just needs to feasible. Where possible, I would like to showcase things we could be using now, but otherwise, I need things that will work on a large scale, and be replenish able. The biggest one is a plastic alternative.

  17. So is the only problem with synthetic bone the collagen? Hypothetically speaking, if we found a way to synthesize collagen on a practical scale what would be the materials other environmental drawbacks?

  18. If Ashcrete isolates buildings less how is it considered a solution at all. You'll need more energy to heat or cool down your house.

  19. synthetic bones, mushrooms, 3d printed epoxy blocks, ash concrete, wool and seaweed bricks, and pollution-absorbing bricks. I know we have the technology, but will the economic and political systems adapt too?

  20. What about timber frame houses with loam instead of bricks. It was done over 800 years ago, it doesn't need concrete or plastics, just wood, branches and loam, and I can imagine, there is also a way for making something synthetic like loam.
    Yes, you can't build skyscrapers, but it's not about redoing everything, and 4-5 story buildings shouldn't be a problem. And the bonus is, you have a wonderful climate inside. And you also can move with your house, the material is flexible, so maybe also a good idea for more earthquake rich areas, you can modify your house,… and it looks beautiful.
    Build more timber frame houses! 😁

  21. Compostable house bricks? Wont last 5 minutes in soggy Britain!
    Anyway why not go back to Wattle and Daub? Some Tudor wattle and daub buildings are still standing. Mud straw and horse dung slapped on willow wattle.

  22. the only thing I can consider is cross laminated timber. But honestly, as it stands right now, the only real sustainable architecture is the architecture you don't demolish.

  23. It sounds like if they could develop some sort of rapid fossilization process, the mycelium bricks could be made stronger. If they could figure out a way to replace the structures with the synthetic bone, it could be a pretty interesting, and renewable building material.

  24. Here is an addition to this list, cement mix made using waste iron slag:

    As the cement cures, it pulls carbon dioxide from the atmosphere.

  25. so, for number 5, it sounds like hank is describing mechanized adobe construction lol. I mean, at least those "non-fired bricks" are more regular than normal adobe, but same principle

  26. Nothing there has any practical value. Then your comment that sand and stone is not sustainable but wool derived from animals is… You need to stop sampling those fungi bricks. 😂

  27. Cross laminated timber is a more mundane "future" building material already being used, though not extensively. Has similar mechanical properties to concrete but it's just treated wood glued together in an alternating pattern basically. Construction with materials such as this that are carbon sinks taking off would be nice.

  28. But remember kids: It's the common people at the streets who need to stop using cars and walk more so the emissions go down. Not like it would be because of these big companies at all.

  29. "Sci" is short for science…. Yet you seem to believe carbon dioxide is causing global warming

    By extension, do you also believe the ice ages were caused by cavemen planting an overabundance of trees (sequestered too much carbon dioxide)?

  30. Bones… I mean… sure it sounds cool and all..:
    But did you ever leave out bones for a few years? They get brittle pretty quickly. So if they aren't far under the earth or inside a fleshy-selfrepairstation (aka a human body) I can't see how they would be a good way to build something that is meant to last a hundret years against the elements.

  31. The best thing about bone houses is that we can just use plaster to repair them when they get a fracture and they will heal in a few weeks

  32. Happy to see mycelium here.
    It's also looked at to see if it can be insulation. Because it's good at that. And for packaging instead of stytofoam. Dell has actually done a run or something with this.
    Biggest problems they are facing now. Water resistance.

  33. Brick and concrete, when properly maintained, can last hundreds of years. Building structures that are meant to last two to three hundred years or more is far more environmentally friendly than any biodegradable piece of crap. Retrofitting and restoring current brick and concrete structures is a far more effective use of resources they continually demolishing old structures to build new less durable buildings.

  34. Unfortunately your telling us of buildings of synthetic "strong, yet flexible" bones gave me a mental image of tall structures wobbling like jelly in an earthquake!

  35. Speak for yourself, Hank. I, for one, would LOVE to live in a building made of real bones. Preferably the bones of my enemies. As I don’t seem to have a lot of those, though, I’d be OK with using the bones of those who somewhat annoy me, too. 💀

  36. I like the mycelia.
    I can't put my finger on it, but there's something there. Some way of using fungus to hold buildings together, not build them. Lacing the material with their food. Like the roots of wetlands, the fungus that support trees, silk for cocoons.
    An idea just out of reach.

  37. does anyone know why concrete is environmentally unfriendly? is it mostly the energy to make and transport it? and therefore carbon lower energy sources would be a great help

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