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This should be an economics piece, not an environmental piece. The author states that "one of iron’s unalterable properties is that it rusts" yet further on ack
by brutusborn 5y ago
This should be an economics piece, not an environmental piece.
The author states that "one of iron’s unalterable properties is that it rusts" yet further on acknowledges the existence of stainless steel.
There's nothing wrong with reinforced concrete, but the incentives to produce long lasting buildings are not there. The cheapest bidder will generally win and their building will last the "design life" of the building, but often not much more. The simplest way to change this is to extend the design life, which would result in stainless steels or another more expensive material being used in this application.
- minikites 5y agoIs it a good thing for society to directly incentivize the construction of longer lasting buildings?
- sesuximo 5y agoIMO yes; if the materials cost a lot of time/carbon/resources to produce, then we should make them last!
- autokad 5y agoI agree. Its like one of the few things we can give future generations. 'sorry about the debt, but heres some buildings'
- nickff 5y agoYou're implicitly assuming they'll want those buildings, and I'm not sure they will. Perhaps those buildings will be unsuitable for their activities, or the buildings will be found unsafe for some unforeseen reason. If either of these possibilities occur, the additional time, energy, and pollution you incurred to make the buildings rust-resistant are waste.
- renewiltord 5y agoNo, time is not an externality: maybe time under construction yields to disruption to neighbours under construction and we can charge for that. Resources are fully internalized. If a building needs x sand and another needs 2x sand, the second will pay twice for sand. Carbon is externalized, but that's a general problem. How do we know that making a lasting building is better/worse than having the building not exist / exist and having people driver farther / closer? Simple, for externalities, you directly charge for the externality. All these stop-gap "it costs carbon, so we must make it last 50 years" is like placing massive `if-then-else` statements throughout your codebase and then being surprised when the emergent behaviour of your program somehow results in uglier, more carbon polluting, sicker buildings that are now 100 years old and imposing massive costs on society around them.
- mc32 5y agoJapan builds buildings to last 30 years on average. They tear them down and build new ones. Is it good, bad, something else? I don’t know, except not everyone builds for things to last a long time.
- mortenjorck 5y agoPeople quote this figure often, but it really only applies to detached single-family dwellings, which are commonly built for a single owner. Japan certainly doesn't build larger structures such as office buildings for thirty-year lifespans – no one has floated any plans to tear down the Kasumigaseki Building yet: https://en.wikipedia.org/wiki/Kasumigaseki_Building https://en.wikipedia.org/wiki/Kasumigaseki_Building
- mc32 5y agoHave things changed in the last decade or so[1]? Japanese loathe “second hand” stuff if they can avoid it. This includes property. The service life for buildings is 47 to 50 years or so, for depreciation purposes. Totally unrelated, but I love that 1000 year old wooden temples get rebuilt every 20 years or so[2] because of the religious idea of renewal. [1] https://japanpropertycentral.com/2012/06/what-is-the-lifespan-of-an-apartment-in-japan/ https://japanpropertycentral.com/2012/06/what-is-the-lifespa... [2]https://chrispythoughts.wordpress.com/2012/10/19/558/ https://chrispythoughts.wordpress.com/2012/10/19/558/
- jefftk 5y ago> The service life for buildings is 47 to 50 years or so, for depreciation purposes. That doesn't tell you much: in the US the lifetime of a residential rental building is 27.5 years for depreciation purposes, and 39 for non-residential: https://www.irs.gov/publications/p946 https://www.irs.gov/publications/p946
- mcguire 5y agoPossibly. "A recent innovation in the Japanese real estate industry to promote home ownership is the creation of a 100-year mortgage term. The home, encumbered by the mortgage, becomes an ancestral property and is passed on from grandparent to grandchild in a multigenerational fashion. We analyze the implications of this innovative practice, contrast it with the conventional 30-year mortgage popular in Western nations and explore its unique benefits and limitations within the Japanese economic and cultural framework." The 100-year Japanese residential mortgage: An examination (1995) (https://www.sciencedirect.com/science/article/abs/pii/1061951895900047#:~:text=A%20recent%20innovation%20in%20the,grandchild%20in%20a%20multigenerational%20fashion https://www.sciencedirect.com/science/article/abs/pii/106195....)
- Taek 5y agoMaybe sufficient to require that construction put down enough money to cover deconstruction and cleanup when building.
- dan-robertson 5y agoYeah I think this is a better way to put it. By incentivising long-lasting buildings you are better pricing in the amortised (environmental) negative externalities of tearing down and rebuilding. I see two arguments against: 1. Future buildings will be so much better for the environment that increasing costs today for long lasting buildings or having to wait longer for environmentally better buildings is a net negative 2. Old buildings are typically not useful and so we shouldn’t encourage a future full of them (examples: smaller houses in city centres function ok but aren’t well insulated and could reduce total environmental costs of the city if they were replaced with more dense accommodation; many old churches see little use; many old buildings or rooms of them are no longer fit for any efficient purpose and so are wasting resources, eg banks with lots of space for tellers/vaults/deposit boxes or stock exchanges with big trading pits or warehouses which cannot be converted or even the rooms above shops which often seem to be disused. I have also seen other places where good use is still made of old buildings (typically long lived institutions like schools or societies or universities) though perhaps not as efficient use as might be possible. Obviously there are other cultural arguments for keeping old buildings around (but sometimes I worry regulations enforcing this can be too prohibitive, eg freezing an old building that has been changing slowly over many years at the point it becomes protected).
- sokoloff 5y ago> Old buildings are typically not useful. My 95 year old brick house would beg to differ on utility of old buildings. My prior house was over 230 years old and provided 14 years of excellent utility to me.
- dan-robertson 5y agoOld is certainly relative. A 200 year old house fits more into point 1 than 2 above. A 230 year old office block tends to not be such a well suited building.
- lurquer 5y agoGood point. What hubris for a landowner to assume there will be a need for a building 1000 years hence. Buildings aren’t usually demolished and replaced because they are dilapidated; rather, it’s because the new owner has a different need (and a different aesthetic.) A building that takes 1000 to crumble is just as a much a blight — maybe more — as a plastic bottle that takes 10,000 years to crumble.
- bombcar 5y agoArguably for many buildings we should be going the other way - if the average house is remodeled or torn down in 30-40 years perhaps we should be building out of renewable materials that are designed to last long and no more (think hay bales covered with mud).
- lurquer 5y agoWhy do we not make clothing that can last 1000 years, be passed down, etc.? I contend that buildings, with a few exceptions, are consumables. Whether wise or not, humans like to build new things, customizable to their own tastes. An office building that lasts ‘only’ 50 years instead of 500 shouldn’t be surprising. In 50 years time, for most buildings, even if it could last another few decades, it will be torn down and replaced. That’s just what humans do. States differently, even if everyone at the time knew concrete/rebar would only last 50 years and not the 1000+ years, it wouldn’t have made a difference, for nobody — short of a Pharaoh — has any interest in such a permanent structure. Cities come and go, buildings come and go, rivers and shorelines change, etc. it’s not reasonable to assume the desirable center of activity (either residential or commercial) in which one builds will even be there 50 years hence. So why worry about how long the building will last?
- rm445 5y agoThe nice thing about buildings which last a long time is, the good ones can be kept around. It's the good side of survivorship bias.
- brandmeyer 5y agoOne reason to prefer shorter-lasting buildings is to encourage higher density over time.
- matheusmoreira 5y agoHow can I know if a building was designed to last a long time? Is it the materials, the method of construction?
- ajcp 5y agoYes.
- matheusmoreira 5y agoPlease elaborate. Which materials and methods?
- 0xbadcafebee 5y agoThere is no way to know other than to ask the architect. You can make educated guesses but that still won't tell you. Even then it's up to the contractors to have done everything properly. Or if it's made of stone. Stacking giant stones on top of each other is a sure-fire way to make a building outlive you. After that, the longest-lived buildings that I am aware of are made of wood. The catch is they've been rebuilt 50 times, once per time they burned to the ground. After those, the longest-lived buildings are made of Roman concrete that we can't reproduce. (To give you an idea how insane Roman concrete was, you can go kayaking north of Naples, and kayak through a concrete Roman building that is sitting on piles in the Mediterranean sea)
- rootusrootus 5y ago> Roman concrete that we can't reproduce. That claim seems to date to a particular article written in 2017 that wasn't well sourced. Roman concrete is interesting stuff and has useful properties, but humans have since created concrete mixtures that are far superior. But they're expensive, so it's not too surprising we don't see them getting used in buildings that compare less than favorably to a temple built a couple thousand years ago. Survivorship bias taken to the extreme.
- wahern 5y ago> The author states that "one of iron’s unalterable properties is that it rusts" yet further on acknowledges the existence of stainless Even stainless steel rusts, just more slowly. Roughly 10-100x more slowly, judging by https://www.nrc.gov/docs/ML1124/ML112490377.pdf https://www.nrc.gov/docs/ML1124/ML112490377.pdf and https://www.mdpi.com/2076-3417/10/23/8705/pdf https://www.mdpi.com/2076-3417/10/23/8705/pdf.
- peteradio 5y agoThat doesn't smell right. I've got 15 year old knives that have never once shown signs of rust. A pair of old scissors left in the rain rusted in under a day. That puts the factor to closer to >10000 than 10 or 100...
- soperj 5y agoYou leave your knives outside?
- phkahler 5y agoKnives tend to get washed.
- frosted-flakes 5y agoAnd immediately dried.
- thisisnico 5y agoMy knives started showing some rust spots. I thought there must be something wrong with the knives, but I realized after googling, it was something wrong with how I was washing the knifes... I left it in a tub of very hot water and soap for a day, did this multiple times, viola, rust spots.
- deleted 5y ago[deleted]
- quickthrowman 5y ago> The cheapest bidder will generally win and their building will last the "design life" of the building, but often not much more. The simplest way to change this is to extend the design life, which would result in stainless steels or another more expensive material being used in this application. Just FYI, on a ‘plan and spec’ construction project, all material is specified by the architect and engineers. If the project specs say you have to use stainless steel rebar, then even the low bidder will have it included.
- singlow 5y agoBut on big projects, doesn't the architect often work for the bidder?
- quickthrowman 5y agoNo, the architect works for the building owner (or tenant). The bidder is typically a general contractor.
- windthrown 5y agoI think that comment was asking about "Design-Build" projects which are becoming more and more common.
- fsckboy 5y agobut... there is also bidding for selecting architects, is there not?
- mdgrech23 5y agoI'm not in traditional engineering but I always felt like "specs" only tell part of the story. In your example they may use stainless steel but cut corners by using less of it than they really should or maybe just use really cheap stainless steel which leads to other problems. I've noticed manufacturing companies like big auto will try to solve for this by creating more specs for parts provided by suppliers but that's a losing battle as its always a race to the bottom. Plus now you need large testing teams to verify parts meet all these different specs. Maybe some percentage of the parts do - what do you in that case? The whole process can be a mess.
- kortex 5y agoThere's also basalt fiber reinforced concrete. Stronger than rebar and doesn't rust.
- readflaggedcomm 5y agoBut steel's more ductile, so basalt-reinforcement failures are less gradual, providing less margin of safety or ability to patch repair (all things being equal). It's more similar to glass reinforcement (both available in bars, mats, and fibers), which is seeing increased use, but better than glass.
- kortex 5y agoGood point. I've heard similar complaints about engineered wood (glulam and friends) for structures vs regular lumber. In fires, solid lumber fails gradually and makes lots of noises before it does, whereas engineered wood just goes BANG and fails at some point. I don't think this stops these new products from being used, it's just another engineering tradeoff.
- Animats 5y agoStainless steel rebar is quite real, and becoming more common for bridges. It's essential for concrete exposed to salt water, which includes bridged de-iced with sale. Order now.[1][2] There's epoxy-coated rebar, but that's on the way out. Quebec has already banned it. One scratch, water gets in, and corrosion starts. Also, the epoxy can be damaged by UV, like when there's a stack of rebar out in the sun. [1] https://www.outokumpu.com/en/products/long-products/rebar https://www.outokumpu.com/en/products/long-products/rebar [2] https://stainlessrebar.com/ https://stainlessrebar.com/
- triggercut 5y agoTo build on your very important last point. Material handling procedure is something that I haven't seen mentioned here that is a very real issue too. Similar to agriculture or pharma where entire stocks can be thrown out if stored incorrectly, in many construction and manufacturing contexts your steel can be thrown out for not being stored correctly too (i.e. left at the port in the open for extended periods, or mixed with other metals). Not just steel, but lots of building products (like membranes) will usually be specd with how they should be stored before use.
- rsa4046 5y ago"This means that concrete structures, for all their stone-like superficial qualities, are actually made of the skeletons of sea creatures ground up with rock. It takes millions upon millions of years for these sea creatures to live, die and form into limestone. This timescale contrasts starkly with the life spans of contemporary buildings." This description is fairly accurate. The CaCO3 (used as a source of calcium in the cement component of concrete) is completely decarbonated in a 1450°C kiln in the process of cement manufacture, combined with silica (from shale) +/- SO4 (from gypsum) and sintered to form an anhydrous calcium silicate (clinker: e.g. tricalcium silicate, Ca3SiO5, ‘alite’), then powdered (e.g. ordinary Portland cement, OPC). The skeletal limestone is long gone — and the above decarbonation step is the reason cement manufacturing process is a significant GHG source (in addition to fuel consumption by the kiln itself). Mixing water with the powdered clinker generates a very rapid, exothermic, partial dissolution of the primary silicate. The rapid release of silica results in nucleation and growth of calcium silicate hydrate (CSH) plus Ca(OH)2. CSH binds the remaining unreacted solid mass together, giving cement its durability and strength.