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China used more cement in 3 years than the U.S. did in the entire 20th Century (washingtonpost.com)
230 points by jonbaer on Mar 24, 2015 | hide | past | web | favorite | 151 comments

Pedant: Cement != Concrete. Cement is one component of concrete. Concrete is composed of water, aggregate, and cement.

The video linked to by Gates' blog says[0] "The most important material in terms of sheer mass in our civilization is cement made into concrete" "The chinese poured into their buildings and roads [...] as much concrete in just 3 years as United States in 1 century".

"In modern times, researchers have experimented with the addition of other materials to create concrete with improved properties, such as higher strength, electrical conductivity, or resistance to damages through spillage."[1]

There's more available[2] to concrete these days than what the US infrastructure used up to 2000[3]. Not that 3 years consumption > 100 years consumption isn't impressive, but:

1) not only are we not comparing the same period

2) it's not clear we're comparing the same material

I often hear cement and concrete used interchangeably, but had the difference drilled into me when I worked (doing computer work) in the industry briefly. For that reason (cement != concrete) and potential advancements in concrete (maybe there are new composites that let us use a fraction of what used to be necessary?) it's not entirely clear what the numbers mean, outside of "China is growing fast".

[0] https://www.youtube.com/watch?v=xi7O9pmM_A0&feature=youtu.be...

[1] http://en.wikipedia.org/wiki/Concrete#Modern_additives

[2] http://www.columbiatribune.com/editorial_archive/pollution-e...

[3] https://img.washingtonpost.com/blogs/wonkblog/files/2015/03/...

Anybody that does not understand the difference between cement and concrete is going to be in for a surprise when they mix up a batch of dark gray goop and try to use it for something in construction.

The shrinking alone will cause some interesting effects.

There are a lot of lay-man misconceptions about concrete, one of the more persistent ones is that concrete needs to 'dry'. It doesn't, it needs to cure, it's a chemical reaction that gives concrete its strength, not something going into solution to allow pouring that then dries and solidifies.

Concrete is very interesting material, its history is fascinating and the materials science behind it as well.

Such a simple thing in principle, so incredibly complex. Just like glass another one of those materials with vast depth.

> Concrete is very interesting material, its history is fascinating and the materials science behind it as well.

It's one of those deceptively 'unsexy' materials too from an outsider's perspective: think of steel and someone may think of, what, swords? watches? but think of concrete and someone thinks of brutalist architecture and urban decay. But there's no reason why concrete is any less fascinating and complex than steel.

What I suppose I'm saying is that it has a PR problem, and I'm glad people like yourself are leaving comments like that to help solve it :)

Maybe it's not entirely a PR problem. Concrete is what it is. Its not very sexy to work with. In fact it's a mess and it can be back breaking. You need to make a mould for it or it will get out of hand quickly and in some situations it's not so easy to make a mould so you have to make do.

In fact having recently had to deal with both concrete and JavaScript one reminds me of the other. With js, instead of a mould you need to write tests for absolutely everything or it will start to break down (I wont push the analogy, just saying that it reminds me of concrete)

Now timber is different because it has some inherent structure built in. Much less frustrating and still quite flexible.

Funny, I always thought of writing C as working with marble. An unforgiving and time-consuming material famous for the masterworks created with it.

My neighbor when I was in grad school did her PhD on concrete. Even after being around for, what, a couple of thousand years, there's still a lot to learn. She basically went to work every day and destroyed concrete (and, of course, spent a lot of time studying the measurements to identify failure modes and causes).

The consequences of getting concrete wrong can range from expensive to devastating.

You can build a boat out of concrete. That's kind of cool.


Isn't the Parthenon cast in concrete? Some very beautiful buildings have been made that way.

I believe the Pantheon dome was, not sure about the Parthenon though. But it's definitely very old. A lot older than some people realise I think. But yes, not disagreeing that it can be beautiful. I've seen many beautiful concrete sculptures, but I don't think it's the first thing that springs to mind for many.

Ha ha, yeah, that's the one. What was I thinking.

The replica in Nashville, TN has concrete in its construction. The original, I believe, is made of marble. (but I'm less certain. I've never seen the real one, sadly.)

[1]: https://en.wikipedia.org/wiki/Parthenon_%28Nashville%29

[2]: https://en.wikipedia.org/wiki/Parthenon#Present_building

[3]: https://en.wikipedia.org/wiki/Mount_Pentelicus

You are thinking of the Pantheon. It is a temple in Rome built in the first century, and it has a dome made of concrete. (The Parthenon on the other hand is a temple in the Acropolis in Athens, but not related to concrete)

Concrete ... the perl of the construction materials industry.

Didn't they just recently rediscover how the Romans made their concrete?

it was on HN a few times http://www.bloomberg.com/bw/articles/2013-06-14/ancient-roma...

but AFAIR, the conclusion was "we actually always knew, it's just that it takes too long".

The linked article makes this clear:

> In case you need a refresher, cement is a powdery lime-and-clay substance that is combined with water and gravel or sand to make concrete.

The bit about buildings lasting 20-30 years really surprised me. The Pantheon stands for a millennium, but 30-year-old concrete crumbling? The article cites a Goldman Sachs quote from a tumblr [1] notes at the bottom of the list:

    An estimated 25-30% of China’s cement capacity is low-grade cement
    not used in other countries (P.C. 32.5 grade). 
I'm not a cement/concrete expert, but PC 32.5 does seem to be a low grade. Higher than PKC 32.5 (composite cement) but lower than PC 42.5. So I found this other source that puts it in stark terms [2]:

    According to the China Cement Association, low-grade cement products 
    (all 32.5 grade) accounted for 72% of the total cement output in China 
    in 2013, with the P.C. 32.5 grade cement accounting for 54%.
So 72% of cement was 32.5 grade, and most of that (54/72%) is PC 32.5. I was a bit skeptical at first, but now I really wonder if/when these structures start to crack &/ crumble.

[1] http://ftalphaville.tumblr.com/post/100653486301/contextuali...

[2] http://pg.jrj.com.cn/acc/Res/CN_RES/INDUS/2014/2/19/c6835c29...

uumm, yeah - I'm a concrete guy at the moment. PC = Portland Cement, 32.5 = MPa of force needed to overcome strength [1]. Normal concrete is in the 20 MPa to 50 MPa range and the strength needed is just a design parameter - it's not a quality issue. typically a slab for a house would be at the 20 MPa end and a massive industrial warehouse closer to 30 MPa (something to do with forklift wheels being small and hard), bridge spans etc ask a structural engineer. the fact that China is using a lot of grade 32.5 concrete is more likely due to the fact that they are building a lot of infrastructure that requires... 32.5 MPa strength. NB 'Grade' in the concrete industry refers to compression strength, not a quality statement. Every country has loads of standards about how cement is made, the constituents that can be added and how concrete is batched, delivered, structures designed etc. Cracks and crumbles are more likley due to inadequate design and placement of the fresh concrete. As others say, it's been around for literally 1000s of years but has infinite depth of complexity - i believe MIT found the actual formula for PC around 2010. amazing that we just used it for its bulk properties without knowing the actual chemical formula ;-)

[1] https://www.youtube.com/watch?v=_S-JnRMers8

I think China is going to suffer an epidemic of infrastructure failure in the near future, perhaps as early as the mid-2020s if the 20-30 years estimate is correct.

For comparison, South Korea's extraordinary growth was followed by a series of infrastructure failures in the mid-90s. A relatively new bridge suddenly fell into a river during the morning rush. A department store imploded, killing over 500 people. Gas explosions all over the place. IIRC none of the major accidents in Korea were caused by low-grade concrete specifically, but there seems to be a general parallel between what the Chinese have been doing lately and the "build now, worry about quality later" mentality that Koreans adopted during their period of rapid growth. Both result in crumbling buildings 20-30 years later.

It's already happening. There are high-profile stories of bridges collapsing and so on. I live in Shenzhen right now and was looking for a new apartment during the summer last year. My roommate noted that a lot of the landlords all know that the apartment buildings will be replaced and rebuilt in 20-30 years.

If that's true, the expectation is already there. However, my impression is that this belief stems from this idea that construction will always be happening because that's how the economy rolls.

The question is what percentage of the population believes that this cycle really is the end game and what percentage of the population thinks they're investing into infrastructure what will last their entire life.

Most ordinary people either don't understand the cycle, or even if they do, they're powerless to do anything about it.

If what happened in Korea is any indication, the first generation of apartment buildings will be demolished after 20-30 years, homeowners will be "asked to leave" with as little compensation as the construction company can get away with, and a new block of condos will go up that the previous homeowners just can't afford. In Korea, at least we let the previous homeowners file complaints and protest for a while before we send in the bulldozers. In China, the bulldozers will probably go in first, and the GFW won't let anyone else know what happened next.

This is an accurate picture of what happens right now in China, but limited protests are permitted by homeowners to haggle the price. An extra complication is Chinese can only own their properties for a maximum of 70 years anyway, with many having only 30 or 40 years left on the state-granted lease, so even without the demolition cycle Chinese aren't really looking ahead more than a few decades anyway.

I'm not an expert on this and I may be mis-remembering something I read somewhere once, but I believe the Roman formula for concrete was quite a bit different. The reasons we don't use it in modern construction are: it takes a really long time to cure, and it's made with salt water, which might cause rebar to rust.

China had it's own historical cement recipe, including rice. Recently discovered it may have useful properties that can be reapplied today. http://phys.org/news194411869.html

>The Pantheon stands for a millennium, but 30-year-old concrete crumbling?

It took the wealth of a civilization to produce the Pantheon. We could make more durable buildings if we used stone, too, but do you really want to pay $10m for a house?

according to these stats the US did the same in the last 5 years


That was the first thing I thought when I saw this stat posted a little while ago. "Fine, the stat sounds impressive, but there's a lot of other stats that other countries do more of in the last few years than in the 20th Century".

For example, anyone could write a dramatic headline declaring that we've created more computer chips in the last X months than in the 20th century. That doesn't mean much.

In short, this feel like some sort of crappy statistic handpicked to make China look bad, when in fact it's the whole world that's using a lot more concrete, not just China!

Wait why is this bad? I thought it was crappy statistics handpicked to make China look good!?

Why is progress in countries outside the western civilizations a bad thing?

Don't we want the people who make our iphones and oculus rift headsets and shiny usb-c devices to have apartment buildings to live in?

It;s not the progress that would make them look bad. it's that cement production produces a huge amount of CO2.

Don't we want the people who make our iphones and oculus rift headsets and shiny usb-c devices to have apartment buildings to live in?

I'd rather they had nice houses instead.

Why? So that China experience the 'luxury' of endless suburban sprawl and the myriad of problems it brings. Hopefully China can learn from out mistakes, not repeat them

No. Because a house is simply a nicer place to live than a flat.

It's very possible to have nice houses without endless suburban sprawl. They can indeed learn from our mistakes; have nice houses, but without endless suburban sprawl.

First of all I absolutely reject your claim that houses offer a priori simply a nicer place to live than flats. Sure there exists certain combinations of price point, geographic location and life situation where it holds, but it certainly isn't a given.

Secondly how are you going to build nice affordable houses for 1.4 billion people without sprawl. Are you suggesting completely giving up on urbanization and going back to having countless tiny villages?

There are many very nice places to live in the world that are not afflicted with suburban sprawl and provide houses to live in, yet are not tiny villages. I'm not going to sit here and fill in the gaps in your imagination; I suspect you've already made your mind up.

There are many very nice places to live in the world that are not afflicted with suburban sprawl and provide houses to live in, yet are not tiny villages

Absolutely, but they either suffer from rapidly rising houses prices or no appreciable population growth. If you stick to a population ceiling of say 50k or so then many problems are easy

But we are talking about about places that are seeing up to a million new people show up in just a few years. Building everybody a nice house is neither realistic nor, in my opinion, desirable. We've either got to re-think the whole "everybody gets a nice house" or try to reverse urbanization in favour of lots and lots of small town capped at around 50k population.

I would personally contend that flats are much nicer places to live than houses. I would loathe to live in a free standing house.

But the stats you linked show US consumption of circa 100 million tonnes per annum. The article shows Chinese consumption at about 2100 million tonnes per annum.

So: the US did not "do the same in the last 5 years", and with China currently using cement at ~20 times the rate US is, the claim is very believable.

In China every building is built with cement. In US most homes are built with wood.

From the article:

> And where many houses in the U.S. are made of wood, China suffers from a relative lack of lumber. Unlike in the U.S., many people in China live in high- or low-rise buildings made out of cement.

A critical argument, but unfortunately mentioned towards the end of the article. But overall its a interesting article and this gif [0] comparing Shanghai '87 vs '13, from it gives a good perspective of the modernization (akin to images of Dubai).

[0] https://img.washingtonpost.com/blogs/wonkblog/files/2015/03/...

Is it a critical argument though? Even if single-family homes in the US tend to be made out of wood, that sector does not seem to be that big, and would certainly not account for any major portion of the difference (roughly 6 million new dwellings in US built per year, say half of them wooden houses, say 10 tonnes of cement (ie 60 tonnes of concrete) per house = 30 million extra tonnes per annum, about 1.5% of Chinese consumption).

Dams, roads, bridges, factories, shipyards and large malls high-rise buildings is where the cement goes, and China is using ~20 times more than the US... My reading is that they are developing fast and catching up to the Western world in material standards of living.

The interesting question is...: how long will this momentum last, and will they keep going lont enough to overtake the current first world economies? I can see good arguments for both sides of this question.

Why does such a large geographical region lack wood? Really? Maybe they just don't care and are happy with cement buildings.

Most of China was deforested a long time ago in the interest of expanding farm fields. As another reply you received noted, much of the western territory of current China (which historically was sparsely populated and not part of China proper) has always been arid and has never had forests.

Xinjiang has beautiful gold pine trees on its border with kazhakistan. I was surprised, actually, I thought the whole place was a desert but it turned out to be more lush than much of northern China (at least for the northern part I visited).

What on earth is "kazhakistan"? You mean Kazakhstan?

> Why does such a large geographical region lack wood? Really?

History spanning back >5000 years, using either rocks, clay bricks (which require fire) or wood. North America has huge amounts of timber which wasn't exploited much until very recently, and a relatively low population for the size of the territory (even counting just the US, there were more chinese in 1900 than there are USians today, and the 1900 US population was below the Chinese population around year 1000… the two countries have almost identical surface areas).

Europe doesn't build with wood either, ignoring wood not being a very good construction material for high-density urban spaces, there's nowhere near the amount of raw materials you'd need lying around, and not enough room to grow it in the quantities necessary.

Oh and much of the Chinese territory is completely unfit for lumber growth (too arid, too montainous, or both), and what little would be fit is necessary for food production. China already imports ridiculous amounts of timber as it is.

What are you talking about? The whole of northern Europe is pretty much built with wood (perhaps with the exception of Iceland?). It is a great construction material. The downsides are that it's comparably expensive and the international know-how is low, since few countries have the amount of wood required.

It's also hard to fireproof without modern technology. But you can still build in modules and with modern technology the cost difference isn't that great for low rise areas. Not far from here there's an 8 story building completely built with wood, and higher buildings are not unheard of. For detached family sized houses it's the standard choice. I wouldn't be surprised if it's the same throughout Canada, northern US and parts of Russia.

> The whole of northern Europe is pretty much built with wood

Wooden construction for buildings over a certain size has been outlawed in Norwegian cities and all of Norway historically, so it's actually mostly concrete and stone, although small towns have mostly wooden, detached homes.

In Germany, wooden houses are unheard of. Not sure where you are getting your info.

There are some very high quality German self build companies that use timber frame and glass construction. HufHaus and Weber Haus are two but there are others.


> Revisit: Walton, 2008

> Kevin revisits David and Greta Iredale, who replaced their original house which they designed and built themselves with a German built, precision engineered Huf Haus.

> Esher, 2004

> Kevin McCloud follows a couple who have built houses before, but never on this scale. Their new 'Huf Haus' is designed and made in Germany but delivered for assembly in Surrey.

To quote wikipedia: Germany has several styles of timber framing, but probably the greatest number of half-timbered buildings in the world are to be found in Germany and in Alsace (France) (http://en.wikipedia.org/wiki/Timber_framing#German_tradition...)

Not log cabins, but wood framed "Fachwerk" houses are everywhere in Germany, or at least Bavaria.

Here in Australia, a friend tells me of an expat German friend of his. When she visits people, she likes to shake the internal walls of the houses with her hands and (good naturedly) says "you guys can't build houses for shit". Which is true - Australian houses are generally flimsy, cheap stuff. :)

I am non-American, and I do not understand why (most/some) Americans think think the default/superior housing material is wood. If someone can explain, I'd be happy to learn.

I'm perfectly fine with brick-and-mortar houses (and concrete sky-scrapers). Brick houses have less fuel for fires, better load-bearing properties (pros), although they take longer to construct.

> I'm perfectly fine with brick-and-mortar houses

Brick is just siding. What's the frame made out of?

You can use wood, you can use steel, you can use concrete with rebar. Those are your only real options.

In the US, you will frequently see 2-3 story houses framed with wood and with a brick siding. I'm in one right now. Anything higher than 3 stories will be done with steel or concrete.

Wood is cheaper than steel and lasts for hundreds of years if properly cared for, which is why it's preferred for smaller residential structures.

>>Brick is just siding. What's the frame made out of?

Man, that is going to be a shock to my house that has all of the outside walls, and parts of the foundation, made from brick. Just because your house has a brick veneer doesn't mean that's the only way to do it.

In my particular the case the floors and roof are made from wood. The floor joists rest on the brick walls.

> Brick is just siding. What's the frame made out of?

For brick an mortar houses, the "frame" is also made of brick[1]. All the walls are load-bearing, so there is no actual frame + siding: just brickwork. You have a concrete foundation, then you lay your double-thick brick-walls (for all load-bearing sections - all of the outer walls that are expected to support roofing trusses). Internal walls can be a single-brick wide. The only place timber is used is for roofing.

1. https://en.wikipedia.org/wiki/Brickwork

> Brick is just siding. What's the frame made out of?

Brick. It's bricks all the way down...

To be serious: most houses in India are made of bricks.


There are quite a few all stone building from the dark ages made entirely from stone. Nothing but stone. Not even mortar, I think. They look very similar to modern buildings. If you moved into one today, it wouldn't be a lot less comfortable than it was then.

Byzantine & later Turkish architecture used brick domes and arches as roofing in buildings that are still in good condition. If you stand on the roof, it feels more like a hill than a building.

rammed earth and cinderblocks are used elsewhere too, no?

For a frame? How do you make a floor with cinderblock/brick/etc? Even if it's a single story, how do you make a roof? You need some sort of material other than masonry material.

> For a frame? How do you make a floor with cinderblock/brick/etc?

Same way as usual, except you use concrete or metal for beams, and e.g. http://en.wikipedia.org/wiki/Hollow-core_slab between the beams. For brick, archways e.g. catalan vaults, you can do pretty amazing things with brick archs: http://www.lowtechmagazine.com/2008/11/tiles-vaults.html

> Even if it's a single story, how do you make a roof?

You can do them the same way, though a wood bent to support e.g. a tile roof tends to be more common (having just a wood bent is a far cry from a wood house).

One- and two-story wood structures do very well in earthquakes (a consideration for some of us, anyway). It has good tensile strength, it is not brittle, and it is not very heavy.

Unreinforced masonry, by contrast, is a terrible choice for an earthquake zone. It's heavy, brittle, and has approximately zero tensile strength.

Thanks! You are right falling/flying bricks are not a good idea in an earthquake or hurricane situation.

After digging some more, it seems like cost is another factor.

I suspect our backgrounds subconsciously color our opinions though: my childhood home (and 99% of homes I have ever visited) were brick and mortar, maybe that is why I am partial to it.

Rammed earth (common in many areas of the world) is even worse.

A rammed earth building becomes a pre-dug grave when there's an earthquake.

"I am non-American, and I do not understand why (most/some) Americans think think the default/superior housing material is wood."

It's a strange US tradition. It's also regional. Until 2002, New York State prohibited most wood construction, and Chicago still restricts it severely. On the other hand, in earthquake country, unreinforced brick is prohibited.

(I live in a cinder-block house. It was built in 1950 by a commercial builder as his own residence, and he built the structure like a commercial building. It's very solidly built. This is quite unusual for Silicon Valley.)

A surprising fact about wood is that large-section wooden beams can perform better in a fire when there's a lot of flammable material around. They burn slowly from the outside so they take a long time to fail, making it safer for firemen to walk around inside. In comparison, steel fails by softening and that can happen much faster just by conducting heat through the whole section.

Bricks are a problem in earthquake prone regions. Even brick cladding on wooden frames tends to fall off and hit people on the head.

One thing is brick is not so good in earthquake prone areas.

It is not lack of wood. Check the population, both at country level and at city levels. Take a look at China in Google Map or Google Earth. If you would like to do research a little further, check the areas covered by forrest. Then you might get an answer.

A little historical perspective would help as well. Check how many houses are made of wood in New York City. A reminder: a large number of cities in China have a longer history than New York City.

Very large portions of China, particularly all of the Western half (Xinjiang, Tibet and Qinghai) are mountainous and/or very arid.

Even much of eastern China is mountainous, i miss trees in Beijing's winter (they kind of just disappear until spring, not being evergreens).

True, and overall China has little arable land and comparatively even less woodlands.

In Beijing, there are some thujas (cypress-like trees) around but I agree that Beijing winter is not very colourful. And the yellow wind (i.e. sandstorm from Gobi) that you're about to get there just now isn't nice either, despite being a natural phenomenon.

Nothing that could sustain a forestry industry. Heck, beijing is a heavy importer of live tree transplants.

We haven't had real bad dust storms since 2008, though a few days last year were bad. And the wind does blow out the pollution so....

Not just that: China uses lots of unskilled labor that can work with concrete but not very well with steel frames. They also use more concrete per floor (we have thick walls and floors) as a form of over building since the quality isn't that great.

Singapore, a modern city by any other definition, uses concrete in the same way so they can import cheap construction labor from India.

Using more concrete per floor can make a building weaker just as easily as it can make it stronger. There is some complexity here, more isn't simply stronger.

Right. And no one expects these buildings to last even 20 years. They are optimal for the skills of the workers available as well as short term costs, but that's it.

I think it is the opposite. BECAUSE less steel frames were used, they could hire lots of unskilled labor.

Steel was strictly state-controlled. It had a status of "strategy" material. So it was "scarce". The first generation of uber-rich families were created because these families (of highest government officials) could get their hands on these strictly controlled materials. They simply sold the rights of these materials, not the materials themselves, to the manufacturers at a hefty price.

No, steel really does require skilled construction workers, not unskilled farmer labor.

Steel is heavily used in manufacturing and there is a glut of it now. I hope the day of reckoning for the aristocrats is near.

I agree that steel requires more skilled construction workers. What I said is that because steel was scarce, more concretes had to be used in the construction. In turn, they didn't need to hire that many skilled workers to work on steels, and they could afford to hire more workers to work on concretes.

Think of building construction as a jobs programs for unskilled migrant workers, and why China doesn't move up to better more modern construction methods will make a lot of sense. They have the steel, they have the money, but they wouldn't employ as many people (for low wages, but enough to live) and so the entire point would be missed (I've had this explained to me many times by business men in China).

Similar stories have been written about other parts of the world. They didn't have the same impressive aggregate total of concrete (or the ingredient in concrete called cement) used, but there were impressive housing and road construction figures from Ireland and Spain and many parts of the United States before the housing markets collapsed in those countries. China is still at risk for a housing collapse,[1] particularly because workers' incomes are not rising as fast as the cost of newly constructed apartments, and overall national population growth has slowed. Housing construction in China is propelled by many of the same speculative lending practices that propelled the last boom in the United States, and may not result in all those new housing units being occupied by anyone able to pay enough rent to produce a positive return on investment.

[1] http://www.dw.de/chinas-real-estate-market-weighed-down-by-o...




The fundamental difference between China housing price drop and US is majority of Chinese buy properties with cash or get mortgage with very large deposit like 40%. So the risk of subprime crisis is very low.

Speculation is rampant and a people I know are leveraged on multiple properties, lying to banks to get loans.

The risk of a crisis is very real; even if the risk of default is low, the risk of the marketing seizing up because no one wants to buy at a price sellers are willing to sell at is incredibly real.

Rents in Beijing are pretty cheap now, getting cheaper actually, while housing prices remain rediculously high. Heck, my apartment complex is prime but only about 60% occupied (the other units bought but being held for speculation alone). Something has got to give.

That was true 10 to 15 years ago. It's no longer accurate. China has become a massive accumulator of debt at the consumer level. While it's not as bad as the US subprime situation was, it is bad and getting worse.

Since year 2000, China's household debt has gone from 8% of GDP, to now 40% of GDP as a ratio (the US is 75% by comparison). Mortgage debt has become a common problem in China. At the rate household debt is expanding in China, they'll be up to 60% in four years or so.


You still have to put down a 30% deposit for first home and 60% for a second, which is stark contract to 0% down payment or even borrowed down payment in US.

A main reason people buy properties is the lack of other type of investment. The public in general have no confidence in stock market. Housing is the only thing almost guaranteed to make money. As financial reforms such as allowing investing overseas kicks in, we should see money moving away to housing market.

0% down is very rare in the US among total housing ownership. The average person is required to put down 15%-20%. Even during the bubble it represented a very small portion of all housing and lasted for only a few years.

Home equity is about 55-56% in the US for the entire housing market (owner occupied) and has continued to climb since the lows of the post bubble bust.

That is a very big difference between house-buying patterns in east Asia in general and house-buying patterns in the United States, and has been for a long time. But that didn't help Japan avoid a housing bust, because if builders build on speculation, their debt drags down the economy even if house-buyers don't have comparable levels of debt. Speculative bubbles always leave someone holding debts that they can't pay off when the bubbles burst.

But do Japanese builders build using large loans, surely the historical sense of building houses from your own money would extend to make them fear borrowing more than they can afford to lose.

Well... no bubble is the same, otherwise we'd be able to spot them and avoid them every time, right? If there is a common factor in housing bubbles, it's the extent to which housing moves away from its primary purpose (ie. a roof over a family's heads). In China housing has become a massive source of income for local governments, income for developers, and an investment vehicle for rich people. It has all the signs of being a classic bubble and the only question is how/if the government can deflate it. Also don't forget that a lot of people pay cash because they can't get a mortgage or don't trust the banks, but they still borrow money from friends, family, lending circles or other informal sources - there is often still a wobbly chain of debt behind each purchase.

China went through their industrial revolution far later than the US, this is to be expected, especially with a population ~3x as large.

IN 1900 US population was 1/4th what it is today (76M). The US also had access to a lot more wood per person so our homes use far less concrete. Also, US useless more asphalt vs concrete for roads so it's not exactly an apples to apples comparison.

Based on population one might expect 33 years. Would the additional factor of eleven really be expected from the fact that various developments occurred later? ISTM that the Chinese just really prefer concrete as a building material. It isn't as though all new construction in USA is concrete.

China has access to far more information on architecture and technology in general than the US had in 1900, that would shrink the 33 years down a lot farther.

For houses, America is somewhat an outlier. Most of the world builds concrete houses and America uses lumber.

Wood is a popular choice for smaller (1-3 story) residential buildings in areas that have large timber production and therefore cheapish timber. That's a minority of places, but in addition to the U.S., includes Canada, the Nordic countries, and Russia. It gets less practical for taller buildings, though, which is why the Finnish countryside has predominantly timber-framed buildings, but Helsinki doesn't.

Let's not forget Japan. They import lots of wood from Canada and most houses, temples are made of it. Turns out concrete is brittle, which isn't a great property to have during an earthquake. Wood is strong, light, and importantly, flexible.

There is a trade-off between permanence and sustainability. Mostly, though, lumber construction is only feasible in areas with lower population densities.

Take note that about 20% of the country lives in Earthquake Country, where just about all residential dwellings tend to be built of wood.

That would be fascinating to augment this article. Take all the places that the Chinese have used concrete, look at alternative materials, then add those up in the U.S. and China as well.

That said they've obviously been investing at an outrageous rate since 2000 in modernizing themselves. The U.S. has started on that way before and without centralizing planning in the same way has done it more slowly over time (with a smaller population in 2015, let alone 1900. Important to realize the U.S. population has grown a lot over the past century).

Just to add more data pointsto the discussion, here is a discussion surrounding concrete consumption due to roads.


A rough analogue for changes to the environment in regard to the US might be the logging of old growth forests to fuel construction and urbanization.

Typical of exponential population growth. The past few years of any resource usage will be more than all of the resource usage of human history combined.

Population growth is not exponential but actually slowing. This is one of many misconceptions about demographics - an absolutely fascinating and important subject which gets little attention in the media or schools.

Here's a nice intro from Joel Cohen, a longtime leader in the field:


The rate may be slowing (as expected), but the overall rate has been exponential until now. Like it took us forever to get to 1 billion, but getting to 7 billion took no time at all from that point.

If the growth rate is slowing it is not exponential - a constant growth rate is the definition of exponential[1].

After increasing dramatically during the first half of the 20th century the growth rate has declined for the last 40 years. Looking more deeply into the demographics (by country and age group) it is pretty clear that this decline will continue for many decades to come. The video I linked above goes into some of this.

Most experts currently predict that the world's population will peak (i.e. below zero population growth) middle of this century around 9 billion - although a few say as high as 11 billion or as low as 7 billion. These predictions are way down from just a decade ago.

[1] http://en.m.wikipedia.org/wiki/Exponential_growth

well that and their housing will be built with cement while a great amount of US housing is wood frame construction.

Still its a demonstration of unbound budgets. The future cost of maintaining it all will be the test of time. While much has been made of China's ghost towns quite a few are getting people yet I am curious as to the maintenance being done and in a timely manner. There is also the question of quality, there have been a few newsworthy stories out of China of shoddy construction.

It's frankly amazing that people are still going on about population growth. Anyone who looks at the trends - people are getting richer and moving to cities at a massive rate, and when people do that they go from having 6+ children to two or less - knows that population growth is slowing fast, and will continue to. Population growth excluding immigration is already negative across much of the western world, and will be the case everywhere before long.

In fact, the bigger issue in the western world, and eventually the whole would will be dealing with it, is what happens when this slowdown in births happens. Just as when you got a huge economic boom from having many young people, you get a economic drag when all those people age and have less young people to support them.

I wonder how much was used to build their ghost cities: http://www.businessinsider.com/chinas-ghost-cities-in-2014-2...

This always reminds me of people snickering about how much snow is in their backyard whenever the topic of climate change comes up.

If you subtract the 15% unoccupied rate from your link from the 6.6 gigatons of concrete, it's still a lot more than the U.S. used in 100 years.

people ridicule it because it's so different than the american way, which is to severely restrict housing construction to cause enormous increases in price so that nobody can afford to live anywhere without taking out massive loans, while poor people get kicked out of their homes.

That is not the "American way". That is the way certain areas behave as they try to fight urbanization, but is not the way most areas behave.

Can you give some examples of cities that don't do this? Every single city I'm familiar with does this, though Houston does it less than most places.

It's hard to point to examples of cities that don't do it because it doesn't make the news when a new building is put up in Nashville. It doesn't make the news when a law to limit building height is never even proposed in Kalamazoo. It doesn't make the news when Akron's population increases 3% year over year.

It does make the news when San Francisco's residents start getting driven out of the city. It does make the news when Madison limits the height of buildings downtown. Can you give me an example of people who didn't get a flat tire today? Of course not, because that's just called normal functioning.

so what you're saying is, the media distorts and amplifies the exceptions in order to create a perception of widespread dysfunction, thereby generating revenues through public outrage?

but this only happens in the US, right? not anywhere else, like... china?

Poor people get kicked out of their homes in China too - http://www.theguardian.com/world/2007/jun/06/sport.china

Beijing real estate makes San Francisco look like a bargain.

Also, china doesn't have a property tax, so you can just buy an apartment and sit on it forever, there is no economic pressure (as a property tax is) to put it to productive use.

You can't buy land forever in China the way you buy land in the US. You can only get a 70 years 'land use grant'.

No one expects that to hold, but even if it does, the US has property taxes most everywhere, and you'd eventually pay for your land again and again just by owning it.

It is speculated that China will drop the land use grant when they institute a real property tax.

All of which is happening in China plus the wiping out of massive amounts of historically significant buildings with so much as a thought

There has been massive displacement of Chinese peasants too. By a decree. But indeed - if you look at rates of home ownership in Eastern Europe pre changes - socialist systems indeed seem to prefer affordable housing.

I wonder if sooner rather than later, those ghost cities might actually fill up once they bottom out and become affordable like how bad parts of SF or Oakland or NYC used to be cheap?

Ordos is in the middle of the Gobi. Build a ghost city in the middle of say Arizona, why would they come?

When you need a permit to move to a city and you can't get one for Beijing, the middle of Gobi doesn't seem like a bad option.

Moving to a city doesn't majically get you a job and livelihood. There is already plenty of depopulated country side with plenty of livable space, people go where the actual jobs are.

Edit: looks like things have gotten worse for Ordos: http://gizmodo.com/4-instant-cities-that-are-still-completel...

True, but my point was that in China the government exerts a lot more control on where people can go. Wouldn't surprise me that the Chinese gov't could fill an empty city if they wanted to.

I don't think that is true. Sure, there is the hukou system, but migrant workers have been free to move around since the 90s, and they do.

If you handed out hukous in 3rd tier economically depressed new cities, I'm not sure if there would be many takers. And the properties in Kangbashi are all fairly high end anyways, the city hukou-deprived migrant workers probably wouldn't even be welcomed.

China builds a lot of subsidized public housing on the city outskirts of major cities, but no one wants to live there because transportation is bad to where the jobs are.

How much concrete did the US use from 2011-2013?

According to [1], it (cement) has been around ~70 megatonnes in each of those years, while the same site agrees with the article and puts China at around ~2 gigatonnes for each of those years.

Usage in the U.S. took a nosedive in 2008, I assume because of the recession. Pre-2008 shows a local maximum in 2005 of 128 megatonnes; so still an order of magnitude less.

[1] http://www.statista.com/statistics/273367/consumption-of-cem...

cement and concrete are different materials

If you want to be real careful you should say Portland cement.

(because, for instance, the bitumen in asphalt roads is also a cement)

But you need cement to make concrete.

Yes, but if you're comparing usage across countries you probably want to compare the same thing; either concrete or cement.

Indeed but if you want a pretty good estimate you can just whatever mixing factor is most common in China or the US and convert :)

For anyone else that's curious, cement is mixed with water and some sort of aggregate to make concrete.

Don't forget the sand, which is technically an aggregate[1]. Using the wrong sand is a classic mistake being rediscovered in China:


[1]-The concrete recipes I remember always had sand and rocks, gravel and/or pebbles (depending on local availability)

Yes, you want coarsely crushed ('sharp') sand, not sand that has better decorative qualities.

Measuring progress in tons of concrete is like judging programs based on lines of code.

Not really. It's more like observing the number of shipping containers going in and out of a country and deriving some rough figures on the economy from there (or trends).

Lines of code have to be examined in detail to figure out their impact, concrete is the universal component of construction, if more concrete is used there will be more construction going on.

Loads of code means someone put lots of money into it, same as when loads of concrete is poured. It says nothing of the benefit of the program/structure that has been built.

I don't want to dub any specific piece of software the Three Gorges Dam of code. But it surely is out there.

I must see this story come up on the internet at least once a month. Why is this so fascinating to people?

Pound-for-pound, cement is the largest producer of carbon emissions in the world.

It gives a glimpse on the rate of change around us, and out there in the world. This big picture is fascinating to behold at, for many people.


You obviously have never gone out and looked at concrete. How can you not be amazed.

That and it's common usage would probably make it a great linkbait story...

Something like Kurzweil's Law of Accelerating Returns [1] helps explain this ostensibly unbelievable fact. It reminds of a similar statistic about the number of years that passed before a country's GDP doubled. UK did it in 154 years (early 17th century to mid 18th century) and China doubled its GDP in just 12 years [2].

For further reading check out an answer on Quora [3] where I found the McKinsey Global Institute report.

[1] http://www.kurzweilai.net/the-law-of-accelerating-returns

[2] http://www.mckinsey.com/~/media/McKinsey/dotcom/Insights%20a...

[3] http://www.quora.com/What-dont-we-know-about-the-Chinese-eco...

"The growth in any doubling time is grater than the total of all the preceding growth" So maybe any developed country including the U.S. did the same.

How about comparing lumber usage? The U.S. may not have used as much cement, but we probably had more wood available.

P.S. I imagine using cement is more eco-friendly.

Your imagination is wrong, sadly. The cement industry accounts for nearly 5% of global CO2 emissions, about half of which comes from the chemical decomposition of calcium carbonate (which is how you make cement).

so what,as a Chinese I still can't afford a house

I think what is not being discussed is debt. Debt is used to finance this type of growth.

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