I reply here since I see no reply under the right message, sorry
> Source? This says otherwise, especially if you take into account you'll have to do less km in a dense city. If you go by bike it's even less.
Personal considerations and experience, I think no such real study exists mostly because it should be really large. Taking into account all the variable in a real life case ALONE demand much effort. For first you should find data for a significant timeframe, let's say 10 years, measuring the raw materials needed to build a metro in some city, and I think no such data exists, you can get some projects but not a trustable bill of material. Secondly you have to track all buses and trains and their average consumption. Done this you have a generic measure of "how much it cost in capex and opex the public transport system of YouNameIt city", what you miss is a "YouNameIt city" spread equivalent with only private vehicles. In this case you can only measure a large number of people consumption in a spread area, count the cost of the original road network witch likely exists since so much time no one can count and their operational costs. Even if you reach such goal you have just a "first degree measure", you need to take into account resources needed to produce the resources you used to build the city and the spread area transport network, some are easy, let's say cement and sand, some others are far harder, like steel. And so on. You probably need an decade to craft a working model for a state like North Korea (a good one because due to it's politics (Juche) anything there is mostly "domestic", they do commerce of course but much less than other countries and they still have cities and spread are, though get real data on NK might be a bit hard).
To cut it short the "carbon footprint" is a nonsense, sometimes useful but not an answer: a train travel it's far less energy intensive on a modern rail than a truck travel, the material travel, but thing change if you have to count resources needed to build and keep rails vs roads, including exchange nodes, because we do not have rails on the home front door or aside of a cultivated field. If you just count how many tons of steel you can start imaging what cost more and what less. At this scale we have no simulation, non real scientific study, only "I like it let's try" without possible comparisons.
> You're comparing with a new build house, compare with a new/renovated apartment.
I do on purpose because my new home was built in around two months, rebuild the building of my ancient apartment is practically impossible because not only you have to relocate ~53 families for an year or more but also because it's in the middle of a dense EU city where such large demolition than construction size would destroy the traffic of a significant part of the city for an year or more, such EU buildings was simply built considering an eternal useful life, and that's a bubble waiting to explode with damage not much different than those of a nuclear war. In USA something similar have happened with certain big condos collapsed or at least damaged enough to be beyond repair but USA cities tend to be far less dense and younger than EU one so MAYBE some might be rebuilt.
The point is essentially that small buildings with enough ground around can be practically rebuilt, dense area can only be rebuilt in batch like relocating all the people from NY to another place and rebuilt the whole NY, witch I bet no one think it's doable or at least reasonable to do...
> You still need them with spread, only more roads to spread everything around.
Not exactly the same thing, yes, maritime commerce need harbors and having many little harbors and many little ships it's not much sustainable, so you need some "hubs" in the logistic network but having much more room for local production you can do them, and the rest of the logistic network is spread anyway so MUCH simpler and cheaper to be build and evolve. A simple example around me there are enough potential farm to have cows for meat, milk and cheese for the nearby residents, it's definitively not enough for modern living but in a hypothetical spread society it would be normal and actually it was normal in a not so far past where at least milk was generally local instead of import in from 1000-2000km away simply because there it's cheaper than here even with the needed logistic. Do so on scale and it's easy to view you need much less resources. We would anyway import shrimps from South America and India, but the volumes changes much.
> it's in the middle of a dense EU city where such large demolition than construction size would destroy the traffic of a significant part of the city for an year or more
This is completely wrong. They renovate buildings here in Tokyo all the time (normally every 20 years), and it doesn't affect traffic at all. They just cover the entire building in a mesh netting and go to work.
The rest of your anti-cities screeds read like someone who thinks that everyone can be a remote worker.
Renovate like you say means just restore damaged "skin", not rebuild the entire building because it's concrete have reached a reasonable end of life and it's design it's not suitable anymore for the modern time, for that you need to destroy the old building to the ground, evacuate the enormous amount of scrap material, than rebuild and no, not in Tokyo or anywhere else it's doable if the density is too high. Is a common misconception thinking concrete is forever, one we lost decades ago.
Living spread is permitted by remote work, but thanks to remote workers those who are not can WFH in many other cases, like a dentist who can work in the basement while living at the first floor in a small village of single family homes. Thinking this is for remote workers only is a common misconception typical in cities where people often have issues imaging a life outside the city. I was in one dense city, I know the feeling, than I go outside and I understand was false.
>Renovate like you say means just restore damaged "skin", not rebuild the entire building because it's concrete have reached a reasonable end of life and it's design it's not suitable anymore for the modern time, for that you need to destroy the old building to the ground, evacuate the enormous amount of scrap material, than rebuild and no, not in Tokyo or anywhere else it's doable if the density is too high.
1. No, "renovation" means making major changes inside the building. In a condo, this usually means ripping out the kitchen and bathroom fixtures and replacing them all, redoing the walls, etc. This doesn't mean replacing the building; that's called "rebuilding".
2. Yes, buildings here in Tokyo are demolished and rebuilt all the time. It's extremely common. There's apartment blocks near me being demolished and replaced right now. Obviously you've never been here, or any place where they know how to demolish and replace buildings regularly. Buildings here generally don't last more than 40 years because of earthquake standards.
The lifestyle you're suggesting is utterly crazy. You can't have tens of millions of people spread out and driving to various rural destinations all day long; the traffic would be non-stop.
1. witch is useless when the main structure reach the end of life... And it's useless for energy saving purposes, because you can't change the overall design to get more low Sun in the winter and less high Sun in the summer and so on. Rebuilding means demolishing the whole structure to create a new one, with a different design for different purposes;
2. I was in Tokyo for a project and before as a tourist, I've not seen large buildings totally erased and rebuilt but it doesn't matter I was there for a too little timeframe for that, but enough to see how many issues of high density Tokyo have, even the the Japanese have put an immense effort to handle many of them.
About the lifestyle I suggest, here in EU:
- Nederland, 425.4 humans/km², 81.3% live in single family homes
- Belgium, 381.79 h//km², 77.6% in single family homes
- France, far less dense, 62% in single family homes
- Ireland even less dense, 89.4% in single family homes
While some others like Italy or Spain do the opposite. Accidentally I'm Italian and I'm living in France switched from a dense city to the mountains and have no intention to came back, as many, many others, essentially all that have tried this way, so well, working it does work, it's not crazy, and local services are spread as well offering local jobs to many people in far better living condition than dense cities in the same country. It's a matter of choice, and I bet the late night Tokyo metro show the effect of density on humans.
It's not a matter of choice; your lifestyle is a luxury. If everyone lived like that, there wouldn't be enough liveable land on Earth for them all, and enough land to grow food to feed them. Get a clue.
> people who actually have crunched the numbers come to different conclusions.
Do they? Because so far I still have to find a complete analysis witch show to be something different than interested PRs...
Also I observe that some countries, like the Nederland, with a very high population density are among the biggest producer of meat and co in EU, while 81.3% of the population live in single-family homes...
> Source? This says otherwise, especially if you take into account you'll have to do less km in a dense city. If you go by bike it's even less.
Personal considerations and experience, I think no such real study exists mostly because it should be really large. Taking into account all the variable in a real life case ALONE demand much effort. For first you should find data for a significant timeframe, let's say 10 years, measuring the raw materials needed to build a metro in some city, and I think no such data exists, you can get some projects but not a trustable bill of material. Secondly you have to track all buses and trains and their average consumption. Done this you have a generic measure of "how much it cost in capex and opex the public transport system of YouNameIt city", what you miss is a "YouNameIt city" spread equivalent with only private vehicles. In this case you can only measure a large number of people consumption in a spread area, count the cost of the original road network witch likely exists since so much time no one can count and their operational costs. Even if you reach such goal you have just a "first degree measure", you need to take into account resources needed to produce the resources you used to build the city and the spread area transport network, some are easy, let's say cement and sand, some others are far harder, like steel. And so on. You probably need an decade to craft a working model for a state like North Korea (a good one because due to it's politics (Juche) anything there is mostly "domestic", they do commerce of course but much less than other countries and they still have cities and spread are, though get real data on NK might be a bit hard).
To cut it short the "carbon footprint" is a nonsense, sometimes useful but not an answer: a train travel it's far less energy intensive on a modern rail than a truck travel, the material travel, but thing change if you have to count resources needed to build and keep rails vs roads, including exchange nodes, because we do not have rails on the home front door or aside of a cultivated field. If you just count how many tons of steel you can start imaging what cost more and what less. At this scale we have no simulation, non real scientific study, only "I like it let's try" without possible comparisons.
> You're comparing with a new build house, compare with a new/renovated apartment.
I do on purpose because my new home was built in around two months, rebuild the building of my ancient apartment is practically impossible because not only you have to relocate ~53 families for an year or more but also because it's in the middle of a dense EU city where such large demolition than construction size would destroy the traffic of a significant part of the city for an year or more, such EU buildings was simply built considering an eternal useful life, and that's a bubble waiting to explode with damage not much different than those of a nuclear war. In USA something similar have happened with certain big condos collapsed or at least damaged enough to be beyond repair but USA cities tend to be far less dense and younger than EU one so MAYBE some might be rebuilt.
The point is essentially that small buildings with enough ground around can be practically rebuilt, dense area can only be rebuilt in batch like relocating all the people from NY to another place and rebuilt the whole NY, witch I bet no one think it's doable or at least reasonable to do...
> You still need them with spread, only more roads to spread everything around.
Not exactly the same thing, yes, maritime commerce need harbors and having many little harbors and many little ships it's not much sustainable, so you need some "hubs" in the logistic network but having much more room for local production you can do them, and the rest of the logistic network is spread anyway so MUCH simpler and cheaper to be build and evolve. A simple example around me there are enough potential farm to have cows for meat, milk and cheese for the nearby residents, it's definitively not enough for modern living but in a hypothetical spread society it would be normal and actually it was normal in a not so far past where at least milk was generally local instead of import in from 1000-2000km away simply because there it's cheaper than here even with the needed logistic. Do so on scale and it's easy to view you need much less resources. We would anyway import shrimps from South America and India, but the volumes changes much.