Buildings made with fungi could live, grow, and then biodegrade | Hacker News Reader

Buildings made with fungi could live, grow, and then biodegrade

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128 pointsznpy96 comments

Why not just create buildings designed to last hundreds of years instead?

In many European cities (at least those that avoided becoming battlefields) there are apartment buildings hundreds of years old. I live in a 200 year old building built during the Austrian Empire, which has gigabit fiber amongst all of the other modern conveniences.

The interiors are typically redecorated every 20 years and the apartments themselves overhauled (ie. replace the floor, update wiring) about every 50 years. The facades and roofs are periodically maintained by the city.

The walls between neighbors are about 50cm of solid brick, so I also have complete silence and isolation.

One of the tricks of modernity is to constantly lower the standard of living, claim that standard of living is actually based on something like the number of pixels on your TV, and say "look how much cheaper things are getting, and the standard of living is going up!"

Durable buildings, good food, and robust societies are all capital-intensive to construct, and huge amounts of capital have been destroyed and/or transferred away from you by certain post-modern political movements, so it's no longer viable for everyone to live in a good solid building with plenty of space. Instead, you have to live in a cheap pod apartment with thin walls. But don't worry, they'll remind you it's more efficient, greener, etc. You may not have a good kitchen, but you can order a bug burger to be delivered by a subliterate third-world indentured servant. Very modern and eco-friendly!

If you have a plan to house 7+ billion people in "durable buildings", feeding them "good food" living in "robust societies", I'd love to hear it.

No need to be snide about it, OP simply suggests better standards for us all.

These will require making fundamental changes to how we live, build, farm, create. There is no master plan in the end, but an ideal of a reliable and sustainable future is a good place to start at.

The solution is to stop debasing our currencies by printing insane amounts of money, as the parent poster is implying. If the goal was to create higher-quality goods every year rather than cheaper, lower-quality goods then the market would naturally develop this way. But we are constantly forced to reduce quality to maintain profitably in an easy-money world.

As an example of how this affects the real world, notice how the prices of good things - high quality meat, cheese, seafood, housing, education, healthcare - continue to rise every year well above the supposed “true” rate of inflation.

You do realise that it's those very same people who become builders, bakers, etc?

I'm even convinced that we actually have a lot of inflation but instead of decrease of the value of money we get decreased value of the base function and durability of our goods. Everything is getting worse because our financial system can't handle durable goods.

Inflation is caused by lots of people having excess money to spend. What we're doing now is we're increasing the money supply but instead of letting the money spread out we've built huge dams around it.

With all of the money in big dams, it's not being spent, so we're not seeing inflation increase with money supply.

I heard the situation since roughly the year 2000 described once as "in-deflation": inflation in everything you need (housing, health care, tuition, food, etc.) and deflation in the wages paid for labor and the cost of manufactured goods (due to deflationary pressure on labor).

I think in-deflation is the early 21st century's analogue to "stagflation" in the 1970s.

This results in an economy where for example state of the art manufactured goods cost the same or even less than a large grocery store run. The primary cost in a TV, washing machine, air conditioner, or tech gadget is labor, and labor is subject to intense deflationary forces. Food on the other hand is tied to the costs of things like land and energy that have kept up with inflation.

It's the result of inflationary monetary policy combined with aggressive labor outsourcing, labor-unfriendly trade policies, union busting, and automation. These latter forces place tremendous downward pressure on wages. Inflation is therefore highly concentrated in things that are not subject to these forces: assets, resources, and things that are really hard to automate or outsource.

Housing has inflated to the most insane degree because it's an asset (and thus soaks up surplus dollars), takes a lot of resource inputs, and its manufacture is effectively impossible to outsource. Triple whammy.

Washing machines are a good example. The old ones are still running 40 years later and the new ones you're lucky if they don't fail the day after the warranty expires.

This could easily be selection bias.

The only 40-year-old washing machines you run into are the good ones, because the bad ones were scrapped a long time ago.

Also repairability - if it is easy to acquire or (or even spot manufacture) replacement parts plenty of things can lost quite a long time (in the theseus ship sense).

Old bricks and old buildings are fine, they've already been made. But making bricks is pretty energy intensive. Brick laying requires mortar, which requires cement, which results in a lot of CO2. Brick houses are heavy, and require strong foundations. Usually concrete these days, again, lots of CO2. I have no idea at which point it makes sense to grow buildings out of fungi, but if they are a greener alternative to brick & mortar then it seems like an avenue worth investigating at least.

Just to get a frame of reference: How much CO2? I'd assume that building once, and then not having to replace it for hundreds of years is the long con and more energy-efficient, if that's the metric we're going by.

Cement production accounts for ~7-8% of all global CO2 emissions. Wikipedia cites sources which claim ~900kg of CO2 is produced for every ton of cement. It's possible that frequent rebuilding could be more emission-efficient.

This entire debate is silly without numbers, but even worse it's missing the point - 38% of UK CO2 is from heating. Most of CO2 is produced to heat and cool building while the stand, not to build them.

Even tiniest improvements in quality of building, it's heating system and insulation will result in dramatic changes. This favours something well built, well insulated, with a heatpump, high thermal mass, and most importantly with heat recovery ventilation. Not hastily constructed crap that goes to shit in 30 years.

IMO the bigger question are: why does cement produce CO2? Could we use a different kind that doesn't? Could we capture CO2 from the atmosphere to produce cement, making it a closed loop?

Cement is a binder mostly made up of Ca and Si oxides. It produces CO2 mainly from the heat input required in production, pure and simple.

I have not heard of any carbon capture technologies that are more efficient than trees and oceans, so the best we can do is facilitate a process that generates less CO2 from fuels spent.

In order to produce CO2, the cement has to contain carbon. Where does that carbon come from? Potentially, we could use plants to capture carbon, and put plant matter in the cement. We could also use chemistry and catalysts to skip the plants. It might not be energy efficient, but maybe that doesn't matter. You can use solar panels and run your cement-generation-reactor only during the daytime, as well as put measures in place to cut back on cement usage. This problem is solvable, it just needs creative thinking and an active decision that we are going to solve it.

One of the inputs in cement manufacture is limestone which is Calcium Carbonate. That is ground and heated at high temperatures with clay minerals to produce portland cement.

So CO2 comes from the reaction between limestone and clay. And comes from burning natural gas or coal to generate the heat needed to drive the reaction.

So we use solar instead. We might not even need solar panels, we could potentially use one of those solar thermal reactors with an array of mirrors pointed to a central focal point. They can produce heat up to several hundred degrees C AFAIK.

Old brick buildings use a limestone based mortar, which actually absorbs CO2 as it cures.

Don't lime based mortar still require the O2 to be driven off through heating to very high temperatures? Isn't that the same reason portland cement production creates high levels of CO2? Or is the CO2 produced during the curing stage of cement?

Chemically they are net-neutral only if they are non-hydraulic lime, but hydraulic mortars do continue to absorb some CO2 over time.

Separately, they are nearly always heated with fossil fuels, but, unlike steel, it's not chemically helpful to do so.

Why aren't stone foundations more common? There's lots of modern cutting methods and everything is done anyway with an excavator. Why is it always concrete? Concrete can't handle water.

Labour. There's a reason CMUs are shaped like bricks. And concrete can handle water just fine if proper waterproofing and draining systems are included in construction.

> concrete can handle water just fine if...

Concrete itself doesn't handle the water, it's being protected. With quite brittle technology. In the long term these kind of ifs don't tend to work. You want to minimize the number of ifs if you want to build something that stays put for a long time.

I visited a friend of mine out in Lancashire in the UK one time after I had just bought a home on the west coast. I mentioned that my home was quite old: It was a craftsman built in 1908. My friend quipped that his home was one of the newest on his street, at 250 years and counting.

On the one hand, I absolutely love the idea of creating lasting structures that stand the test of time and can serve many generations of people. That seems reasonable and cost-effective from a long-term perspective.

On the other hand, I also visited Japan and I learned that people generally tear down their houses and rebuild from scratch every 20-30 years. I don't know all the details about how this system came to be, but someone told me it was for a few reasons: One, lots of earthquakes meant making housing more cheap and replaceable reduced the impact of the shakes. Two, the financing structures are impacted by the Georgian land-value taxation system Japan implements, meaning almost everywhere the land on which the building sits is 10-1000x more valuable than any building could be. And three, the idea that future generations will have different needs and wants, and so having a house built hundreds of years ago that's perfectly fine structurally but ill-suited to modern living is an outcome to be avoided.

That also hearkens to something Joel Salatin said about how he thinks about building capex on his farm: He plans for any given structure to last 20-30 years. If it makes it that long, it's almost certain the farm's needs have changed enough that you'd want to tear it down anyways.

I don't think there's an obvious answer here, and maybe it's like most things: The best solution is a variety of solutions.

Japan is at about the same latitude as California, and completely surrounded by water. The need for thick insulation is much less.

Perhaps that's true on average, but there are some very cold places in Japan and the housing is the same there as I understand it: built to last 20-30 years.

For example https://en.wikipedia.org/wiki/Asahikawa#Climate

Anyone who lives in a Japanese house will attest to the awful feeling of waking up in a freezing house in even a mild winter in Tokyo. Or the murderous hot of summer that it has its own word for trying to escape it (避暑). The poor insulation means you can spend myriads of yen and never feel comfortable inside.

Incidentally, this is also a reason my colleagues wanted to go to work. Offices are often better setup than homes. (At least this was their excuse to stay at work)

Less than northern continental climates sure, but you're ignoring the jet stream. Tokyo is considerably colder in the winter and hotter in the summer than, let's say Monterey at a similar latitude.

> I also visited Japan and I learned that people generally tear down their houses and rebuild from scratch every 20-30 years.

From what I understand, the Japanese has a strange cultural aversion to housing that's been lived in or in which people died.

This was what I observed as well when living in Japan. While the other reasons given seem to be valid as well, the most common reasoning for new home construction I heard amongst my coworkers was this cultural/spiritual reason.

Yea, my dad was threatened with a lawsuit because he didn’t disclose my grandmother died in her bed.

This was in San Francisco.

"Departures" a Japanese movie from 2008 deals with this phenomenon in a very pleasing way. I recommend it.

Your friend was exaggerating. 250 years is very old even for the UK. Most houses are less than 100 years old, though 1908 wouldn't really be considered unusually old.

A quick Google proves you wrong, Georgian period began in 1714 with King George I and lasted until the death of King George IV in 1830. There are certainly many Georgian properties in London right now, for example my brother rents one...

London isn't representative of the UK mate. Likewise, OP said on average, not that it wasne possible.

The bit I’m saying is wrong is “your friend was exaggerating” by saying his house was the youngest on his street at 250 years old. It’s perfectly reasonable to say that and in many parts of the UK extremely common.

Good point. Of course, you'd imagine if many on the street are older houses then most are.

There were ~11 million homes in England in 1939, and ~23 million in 2019. Even if we allow for single homes being split into multiple smaller ones, and assume that every 1939 home was still standing in 2019 (ignoring the effects of the Blitz, and of the slum clearances of the 1950s and 1960s), that would still suggest that half of English homes are less than 80 years old. I doubt things are significantly different in the rest of the UK.

No. Old houses are not distributed on average, the point I was making is it’s a perfectly reasonable thing to say that a 250 year old house is the youngest on a specific street. Could easily be true, common even.

You need to improve your Google game:

https://www.statista.com/statistics/292252/age-of-housing-dw...

> the Georgian land-value taxation system Japan implements, meaning almost everywhere the land on which the building sits is 10-1000x more valuable than any building could be

How does that work out, wasn’t the point of Georgian land value tax to reduce land value?

Yeah, that seems like opposite of Georgism. You don't have to look very far to find examples of land being worth much more than what's built on it, that's the case in much of the US.

I would disagree and say that most land is cheap in the US.

I'm not saying that it's the case for most land, I'm just saying that the land that people live and work it's not uncommon. Over 80% of Americans live in urban areas.

I agree that the best solution is a variety of solutions, there's no one silver bullet that's going to save us all.

I've heard this line about the Japanese before and I wonder how they got to this point. I recently learned about the Japanese housing bubble associated with their pre-90's collapse, and it seems the conditions before that crash were very much more similar to what the real estate market is like in the US today, with big conglomerates and banks able to buy and hold huge amounts of land.

I think the responses to the crash probably has something to do with it, the Japanese response was very different from the USA's[0]... but I haven't unpacked this fully enough to have a final analysis.

[0] https://www.lynalden.com/economic-japanification/

Jelly with all your hones, amazing how people back then built structures that outlive mutiple generations of them

You just don't see those buildings that did not survive. Survivorship bias.

Another reason might be lack of engineering science. People did not now how thick wall should be, so they built them as thick as possible. Nowadays people prefer to build cheap structures which will work good enough for their needs and will have guaranteed lifetime of 50 years. Science made it possible.

Historical post-WWII housing stock in Japan was for the most part pretty... bad. Not the kind of thing you’d want to keep around.

Also construction standards for earthquake resistance changed (iirc in the late 90’s) so values even for rentals fall off a bit of a cliff for older houses. Modern housing is a lot better though so habits may change.

Not sure what you mean about land tax though. If anything being taxed annually on land holdings should drive the value of land down. I’ve even heard of people trying to give away land in rural areas to escape land taxes.

Yes, and this is why American housing, including apartment housing, ticks me off so much. The building materials are crappy and neighbors can typically hear each other ("luxury housing" may not be affected as much when everything is built from concrete, including the floors/ceilings). Cities have laws about how much surface area ought to be covered with rugs to reduce noise for the neighbor below while walking.

Yes, please build to last. It will discourage crappy design, it will be more forward thinking because you can't just tear it down or slap it together in 3 months, it will be more economical in the long term (better insulation than the 2x4 cardboard boxes common in the US). Building materials are less toxic. It will also buck the consumerist glut that currently affects every sector of the economy and has led to enormous waste and poor quality. Actually, that's really the way in. To buck consumerism, an ethos of quality and classic style and design needs to be promoted. Anything else should be shunned as cheap and low quality.

The economy grows at a per capita rate of about 2% per annum. The average citizen in 200 years will be approximately 50 times wealthier than we are today.

It makes little sense for the comparatively poor consumers of the 21st century to pay extra for housing for the comparatively rich consumers of the 23rd century. Just as it doesn't make sense for a 20 year old to take out a huge mortgage to buy a big house that he won't need until he's 40 with a big family. It makes much more sense for us poor people or the present to save money by building cheaper, shorter-lasting housing, and let the filthy rich people of the future pay for it later.

> The average citizen in 200 years will be approximately 50 times wealthier than we are today

I wish I could share your optimism. If the current wealth gap trend is continuing, the future won't be much different than nowadays. It's even harder to buy a house and/or build it today than let's say 30 years ago.

The current wealth gap is shrinking, so I'm not sure what trend you're referring to. It may be increasing in your country and many others, but globally the average citizen is far better off today in virtually every material and health metric.

A lot of nice plots here: https://ourworldindata.org/global-economic-inequality

A more direct response: https://www.weforum.org/agenda/2018/04/its-time-to-totally-c...

That's because poorer countries are becoming less poor It does not prove that an average person in the currently wealthy country will be 50x wealthier

Yes, that's what I said, and even included the second link to make that more explicit. I don't mean to imply that the wealth gap in wealthy countries is decreasing. The point I am getting at is that it's far more difficult to make the argument that the wealth gap is increasing, full stop. It's quite likely that the vast majority of the world will live in countries where it's decreasing.

Currently wealthy countries can very well collapse.

Maybe in 50 years people will want to move to South America, not the USA.

Your average customer may very well be 50x wealthier, but they may be in Costa Rica instead of the Silicon Valley

The economy grows because value is being created. If we follow your advice and create less value, economic growth measured by GDP will finally become a total vanity metric of who can create the most bullshit jobs and the most taxable transactions without creating any output. It stops being a good measure for wealth creation.

I’m sorry, but this rant does not make any sense. How is building housing a “bullshit job” that doesn’t “create value”. Housing is pretty much the definition of a valuable good.

If your point is that short-lived housing is “cheating” because it has to get replaced faster, you do know that capital depreciation is included in GDP calculations, right?

Otherwise, I simply don’t see whete you’re coming from. Short-lived housing stock is just as valuable as long-lived housing stock. I care whether I have a roof over my head, not whether it will be the same roof in 100 years. For example in Japan the average home is knocked down and rebuilt every 26 years. And it works fine for them.

Even better in fact, Japans one of the only countries where the cost of housing hasn’t creased increased in the past 20 years. It also means that the average Japanese home is more up to do date with modern amenities and stylings. Much better than the drafty, damp homes with low ceilings, leaky plumbing, and outdated floor plans that you find in Britain’s century old housing stock.

I will explain the connection for you: A bullshit job is a job doing busy work, which is not actually needed. Building 10 homes designed to break instead of just one designed to last and be done with it, to me very much seems like a bullshit thing to do. You will have created more transactions, have grown the GDP and have made future people richer on paper. All you have actually done is to create less quality goods and cause more harm to the environment.

Living your life in 4 different huts made of paper mâché is not the same as living in one properly built home. It's not like the hut will be good for 19 years and then suddenly fail you. It will be worse from day one, while a proper building can hold on to its quality.

I am coming from a standpoint of valueing actual quality of life improvements. I also value nature and realize that there is climate change going on.

> Why not just create buildings designed to last hundreds of years instead?

Because no one can anticipate if the land a home is built on will be valuable in some exact moment in the future.

For example, should we build durable homes in Miami at all? There is sunny day flooding in North Beach right now.

And yet. A part of town literally not habitable in the far future, but still, its prices are high.

If you're so confident you know what land is going to be worth, go buy it.

The cost mostly. While we could build very well planned long term buildings, as a owner you care max about 1 or 2 lifetime (you, maybe your kids) so the premium to get it to last 10 generations isnt worth it.

Mix with that governments elected to ease ownership access whatever you end up owning and the fact these old houses you talk abt were a sort of dick measuring multigenerational competition between rich bourgeois and you understand why we build what we need rather than what 3 generations down the line would have wanted us to pay the cost of so they dont have to.

European capitals are probably also the very rare exception of cities that have roughly the same population numbers as they had 200 years ago. You can't do this kind of thing as easily in a city that is growing quickly.

Population of Copenhagen in 1840: 120,000.

Population of Copenhagen today: 795,000.

And that's just Copenhagen proper, a relatively narrow geographical definition. The city has expanded to absorb many of the outlying towns, turning them into neighborhoods and suburbs. The population for Greater Copenhagen is 1,335,000.

An over tenfold increase in population (and a significant increase in area) can't really be said to be "roughly the same population".

Have other cities grown more? Sure. But cities 200 years ago were all tiny compared to today, all over the world.

Yea I phrased this wrong, you're right of course. What I meant to say was that the highly urbanized areas in which these 200 year old apartment blocks stand were already urbanized back then, while newer apartment blocks are probably in areas that were pastures or villages back then. So it wouldn't have made sense to build high density apartment blocks there 200 years ago. European capitals are some of the few places that had this kind of urbanization 200 years ago.

The house I live in was built around the time america was founded and will most likely outlive me as well.

Its not an apartment building either, it's simply been taken care of since 1770ish

It's one thing to produce insulation, or bio-bricks from kiln dried mycelium, but to leave the mushroom mycelium alive seems like a hazard to both the occupants and surrounding building materials. Not only will the mushrooms release spores which can get into peoples lungs, clothing, furniture, etc. and then start consuming those materials, but the mycelium itself will continue to spread into any organic matter that it is in contact with.

yeah like, imagine you build a 10 story apartment building, and one small portion of it has live mycelium that accidentally survived, or some weird manufacturing lemon/error... then 5 years later you have to tear down the building due to the mushroom infestation

This is already happening in many attics and walls. Also that's why new construction technology deeply focuses on airtightness. The airborne particles you are pointing out is symptom of bad building science, not a cause.

As for consumption of adjacent materials, near the end of the article the talk about how it can be triggered.

"There's been buzz lately about mycelium" -- Well, Paul Stamets has been talking for decades. Did a TED talk, amazing other videos - a fantastic Joe Rogan Podcast etc.

Mycelium is AMAZING - and I really hope that we start using it in the myriad ways it is versatile for so many different applications.

---

Have you Seen these Paul Stamets vids:

Joe rogan: https://www.youtube.com/watch?v=mPqWstVnRjQ

Ted (6 ways mushrooms can change the world: https://www.youtube.com/watch?v=XI5frPV58tY

https://fungi.com/

https://en.wikipedia.org/wiki/Paul_Stamets

I recently learned that only about 200,000 out of the estimated 2-5 million species of fungi have been identified.

It's such a huuggee gap of knowledge! The natural world has so much more weird stuff to offer, hope we will learn a lot from these strange non-plants non-animals

No big thing there, parts of my house are biodegrading already. :(

Sounds like you’ve replaced one fungible asset with another.

Qualchouse will be providing the fungi drivers and although potentially functional for a few decades, after 2-3 years your buildings existence will stop being supported by the upgraded city.

Neighbors will force you to upgrade because even though the pesticides for the new fungi eating microorganism are compatible in principle they are only provided in a container designed for the new buildings' sprinkler systems.

The "open-the-container" and the "create-open-pesticide" communities soon discover that competing is a thankless multimillion costs job after producing nothing.

Eventually after an upgrade the lucky ones who got unlocked on the outside end up forming militia to take control of the nearby caves. Humanity will have thus realized the early 19th century dream of a pastoral life.

You forgot to mention that time when some of the buildings, due to a strange bug in the fungi specs, started to digest their inhabitants, which was not discovered before about two million people worldwide disappeared without leaving a trace. Qualchouse apologized and provided an upgrade almost immediately.

Fungi are one thing I both don't really understand and find extremely fascinating. If anyone has recommendations for comprehensive books or other materials for laymen I'd be grateful.

Most people would probably recommend Paul Stamets' book Mycelium Running in response to this question. I haven't read it personally (despite owning 20+ mushroom books), but that's probably the closest to what you're looking for. Langdon Cook's book The Mushroom Hunters is also a lot of fun, but it's definitely not comprehensive -- it's just stories about the commercial mushroom harvesting world.

If you want to get into mushroom foraging then the best way to learn (in addition to joining your local mycology club) is by getting some of the picture books, e.g. Mushrooming Without Fear and Mushrooming With Confidence. (Field guides aren't good for beginners, even the simplified ones.) If you're in the northeast, Lawrence Millman's book Fantastic Fungi of New England is also great.

I recently read Entangled Life: How Fungi Make our Worlds, Change Our Minds & Shape our Futures. It was a pretty good read and I learned a lot about fungi: https://www.goodreads.com/book/show/52668915-entangled-life

There is a beautiful video documentary created by a fungi photographer who has contributed footage to productions like Planet Earth and Our Planet. It really gives you a sense of the vastness and beauty of the fungal world that’s all around us yet invisible to most. Since watching it I’ve made it a point to be more observant when I’m outside and as a result I’ve been spotting interesting mushrooms all over the place.

https://youtu.be/KYunPJQWZ1o

Maybe I am being dense, but wood also biodegrades, and is an easier building material to use...

The wood doesn’t self-heal or continue to grow once it is cut. Given that they grow some of this material from wood or wood dust, you could potentially recycle your old wood into a new material directly.

Also some wood is being treated in buildings which makes it hard to recycle wood. Specially if this acts as insulation or earth contact, it will be an improvement.

Way cool. I'm wondering if this increases (or decreases) the likelihood of black mold in the building.

Probably decreases, assuming everything is working as planned. Mycelium building materials will need to be kept dry in order to prevent them from consuming their media and sprouting mushrooms, and these dry conditions would prevent mold. Additionally, the mold and mycelium would compete for the same nutrients, with the mycelium already far more established.

If too much moisture gets in though, it's game over. Perhaps the mycelium bricks/plates can be coated in a sealant.

As long as the fungi is still alive, it should decrease the chance of getting black mold as it is directly competing with the mold, but it has the advantage of already colonized the substrate the invading black mold wants to colonize.

If it's dead then it's just food for whatever wants to eat it.

This reminds me of a Wraith Hive Ship from Stargate: https://stargate.fandom.com/wiki/Hive_ship

Or Tel Mithryn from Skyrim: https://elderscrolls.fandom.com/wiki/Tel_Mithryn

Reminds me of Shriek: An Afterword by Jeff VanderMeer, that literally describes a world where buildings are made of fungi.

Also, wood.

I assume fungi like this is highly flammable. Is that true?

Actually, they're flame retardant [0].

> Mycelium has been found to possess certain flame-retardant properties (e.g. high char residue and release of water vapour) and could be used as an economical, sustainable and fire-safer alternative to synthetic polymers for binding matrices.

[0] https://www.nature.com/articles/s41598-018-36032-9/

As an aside, burn morels are gourmet mushrooms that pop up after fires. The mycelium have already colonized the roots of conifer trees, and they produce fruit after the trees catch fire.

This would not be good for my rare book collection

The smurfs.

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