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Timber Towers Are On the Rise in France (citylab.com)
A reader shares a report: Spurred by concerns over climate change and the negative impacts of concrete manufacturing, architects and developers in France are increasingly turning to wood for their office towers and apartment complexes. Concrete was praised through much of the 20th century for its flexibility, functionality, and relative affordability. In France, the material ushered in an era of bold modernist architecture including housing by Auguste Perret and Le Corbusier. Today, however, wood is lauded for its smaller environmental footprint and the speed with which buildings can be assembled. "Wood had largely disappeared and was seen as a quaint material," says Steven Ware, a partner at the architecture firm Art & Build, whose latest wooden office building opened in Paris's 13th arrondissement earlier this summer. "[But] the energy it takes to put a concrete building up, to run it, and then dismantle it when it becomes obsolete was too much. Using mass timber in office buildings seemed like something we had to do." The production of cement, one of the main ingredients in concrete, generates an estimated 5 percent of the world's carbon emissions. Trees, in contrast, capture CO2, helping offset emissions produced by a typical building process. And then there's the string of other construction advantages that make wood economically appealing. It's lighter, which means digging smaller foundations in the ground. Crane costs come down, as they're no longer hauling blocks of cement hundreds of feet in the air. Driving a nail into a slab of wood requires a lot less energy than driving one into concrete. Months can be knocked off the construction timeline.
Sounds like a good way to have a towering inferno. The stuff we put inside large buildings burns quite readily. But the fire generally stops in a single room. But if you suddenly make everything out of wood, what's to stop the fire from spreading everywhere?
Are they really comparing the energy cost of driving a nail?
Wood has a place but IMO if you want a durable structure use reinforced concrete. Maybe this wave of construction is only expected to stand for 30yrs?
Lumber supply forests are harvested and replanted these days.
>> Today, however, wood is lauded for its smaller environmental footprint and the speed with which buildings can be assembled.
There's no reason we can't just stack IT people in cubes in pole barns. Fortunately, nobody with any talent actually needs to work in a crappy office, so most companies are smart enough not to try this.
If you focus only on CO2 and ignore the annoying forest critters and such, then cutting down (and replanting!) trees is good because young growth sucks up more CO2, which you are going to harvest and use in a building indefinitely.
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Last two /. articles share a theme:
"Timber Towers Are On the Rise in France"
Mysterious Void Discovered In Egypt's Great Pyramid
Death traps
That's actually not so bad, because you simply plant more trees and the problem takes care of itself.
It's long term carbon release of previously sequestered carbon that's the issue.
Recently, as in this week, they completed a low-emission earthquake-resistant timber tower in Portland, Oregon.
Fire risks tend to come from inefficient fire suppression systems and lack of coatings. Or inadequate emergency exits. As we've seen from London, England, concrete towers clad in flammable plastic are more of a fire trap than wood timber buildings are. It really depends on the full architectural design.
-- Tigger warning: This post may contain tiggers! --
I recall a prominent global warming alarmist getting kicked out of the group he was in because he advocated the using of wood as a building material, since using wood in this way is an effective carbon sink.
Using wood as a building material only causes deforestation if people don't plant new trees in their place. No one does that since it's not only bad for business, they'd run out of trees, but it's illegal in any place I can think of. If there is a place in the world that allows for clear cutting of trees and not planting new trees in that space then I'll show you a place that lacks any real government.
Using wood for buildings is good for the environment. If you believe that steel and concrete is better then I'll ask you to show me your math. If you believe that we just shouldn't be building new structures then I'll ask you to show me your age. Saying we shouldn't need new office buildings and homes is something that I'd think would come from a child or someone suffering from senility.
If someone knows who that was that advocated using wood as a building material as a carbon sink, and got shunned for it, then I'd appreciate a reply on who that is.
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CLT and mass timber is the shit. They are also working on LVL veneer based types that are like super plywood vs. the current finger jointed lumber version You trade material cost for labor but you can have a house framed in a day. Also concrete is a carbon emitter for a long time. It is not prone to fire. You can have them CAD CAM all the windows, doors, conduit, and plumbing into the walls at the factory, and it is renewable.
Wood can be grown and harvested sustainably on tree farms where generation after generation of trees selected for structural properties and rapid growth are cultivated. Any such "green" inspired building program should/would ensure that all the timber used comes from such sources. And so yes, building permanent structures out of wood does lock up CO2 as long as the structures stand - whereas CO2 released in the production of concrete is in the air for centuries.
The actual material used for framing a structure has nothing to do with the fire safety (or lack of same) in an inhabited structure. Metal and concrete framed structures are no safer on that count than wood. The fire hazard that threatens life is entirely due to the furnishings and utilities inside the structure. By the time a frame of wood frame building starts to burn the interior is already destroyed, and the inhabitants have either escaped or are dead. Note that modern construction techniques using fire proof gypsum board that isolates the structure from the interior (gypsum does not burn and actually absorbs energy as it decomposes).
Wood is a pretty remarkable material. It is in fact an advanced composite material produced by natural nano-factories. It compares favorably with far more expensive synthetic composites, and beats them all in cost. Used properly (taking advantage of the anisotropic properties of wood beams) a good wood beam comes with a factor of 3 in stiffness/weight ratio of the best performance ofunidirectional carbon fiber epoxy composite, and beats structural steel. Sitka spruce is used in the upper stage of Trident II SLBM missile since it had the best properties for the role, over all other candidates.
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Also there is a fair amount of carbon sequestered in the building itself. That's assuming the building doesn't burn, which is why I won't get into a tall wooden structure.
Don't it Depend on the Tree?
Soft woods like pine grow quick, but the wood is, you know, soft. Wouldn't want to live in a skyscraper made of that!
AFAIK, the hardier the wood, the longer it takes for the tree to grow. That means a long-term investment in your re-planting, and a lot can happen to your plot of re-planted little sprouts (bugs, deer, fires, suburban sprawl, drunk kids on ATV's, massive natural gas deposits) while you wait the lifetime or two for your trees to grow to full size.
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Not really. Most atmospheric oxygen has marine origins.
What's more you can replant forests, although you lose the ecological benefits if the forest you just cut down was virgin as opposed to managed timberland.
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I'm buying termite-related stocks
Table-ized A.I.
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It would be ironic if you write that from a deforestated suburb!
Any sufficiently unpopular but cohesive argument is indistinguishable from trolling.
Termite populations soar as the the rise of timber towers brings the buffet to the buggies!
Wrong. They 'inhale' CO2 and 'exhale' oxygen during photosynthesis. All photosynthetic organisms do so.
Bamboo makes a very excellent building material. It grows faster than traditional forests and can be harvested every other year in most cases and doesn't need to be replanted since it grows in stalks like grass. Every seven years, there is a massive flowering and die-off, but even that isn't an issue since the flowering also seeds the ground.
Processing bamboo into usable beams and planks can be problematic, since the fibers have to be broken and then glued back together in composite forms, and in some techniques, formaldehyde is a toxic component that can remain in the product (problematic to house dwellers if it is released to the building). But when used as a floor covering, it's as hard and durable as hardwood.
For myself, I think the best building material is all the above. Concrete and steel, wood and bamboo, even recycled plastic, that way you get the advantage of the right material in its best application.
The "Insulated Concrete Forms" construction of concrete housing was what I was aspiring to if I ever built a house. Probably won't, unless a tornado knocks this one down, but the advantages were that the ICF house is highly insulated, almost in the class of superinsulated, and it takes a really big tornado to knock it down. What's "inefficient" about that? I don't even live in "tornado alley" any more, but had a "tornado aloft" take down my ham antenna and turn one mighty oak into a very distracted looking oak that somehow survived (but I was betting against that at the time." Didn't touch the house, but if it had knocked it down, an ICF house would have gone up in its place.
Although concrete may seem t to take more energy to put up and take down, what about the maintenance you must do with wood? That requires a lot of materials that take energy to produce also...
Not to mention that unlike a wooden structure, concrete can scrub CO2 from the air after it is built.
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This is absolutely not true, carbonation will only occur where the concrete has access to the outside atmosphere. Deeper in the pour there will be no carbonation unless the concrete is cracked. In fact, carbonation is one of the main problems that a reinforced concrete structure faces, as it contributes to corrosion of internal rebar by raising the pH of the surrounding concrete.
That's solid wood, however, possibly dense old-growth wood. These are modern composites. I have no idea if that makes them more or less durable over a century.
What it likely makes them is hard to repair, unless the particular composite method they used becomes the dominant one. With a quick skim, I see about 4 competing technologies for pre-engineered, mass-produced wood composites. If you build with one and it falls out of favor, it might be tricky in the future to do any repairs. If nobody is making nail laminated timber and you need to sub in cross laminated timber, what are the ramifications?
Velociraptor = Distiraptor / Timeraptor
I saw a construction project in Hainan that used bamboo and coconut fiber to reinforce concrete. They still used some steel rebar, in addition to a mesh of bamboo. The coconut fiber was dumped into the mixer. According to the foreman, the result was lighter, cheaper, and more resistant to seismic shear. But less resistant to compressive force, so it was only used for buildings of 3 stories or fewer.
But the carbon is released again when the buildings burn to the ground.
Wrong. They 'inhale' CO2 and 'exhale' oxygen during photosynthesis. All photosynthetic organisms do so.
Only when the sun is out. Most plants consume O2 and expel CO2 at night.
Nevertheless, trees are a net producer of oxygen (and a very good carbon-capture device) if you don't account for them rotting after they die. But oceans and marine plants are a more important producer of oxygen.
If it weren't for deadlines, nothing would be late.
Learn a little bit about the forest/timber industry before spouting off. They have what are essentially farms where trees are grown for this stuff now.
The trees capture the carbon and it's then stored in that structure. Plant more trees, capture more carbon.
Think about it.
I've seen a lot of this in my area, generally what they call podium construction, where you have a 1 to 3 stories of concrete construction and then build wood frame up to the maximum height allowed, typically 5 stories of wood. As TFA outlines, it is cheap and very fast compared to all concrete, and has become a go-to for mid rise residential. Unfortunately, it makes it possible to cut corners to an even greater degree when it comes to flooring, and fire safety is entirely dependent on active suppression. I have actually seen one of these buildings survive a fire during construction (with a great effort by the fire department), but afterwards it was demolished back down to the podium.
In the end it comes down to labor cost, concrete is surprisingly labor intensive and labor costs are a huge part of construction in first world countries. I've seen some beautiful concrete work done in South America that would be impossible in the US simply because of labor costs - Imagine a 20 story concrete facade entirely finished by hand: Beautiful, but impossible to do in the states.
Also there is a fair amount of carbon sequestered in the building itself. That's assuming the building doesn't burn, which is why I won't get into a tall wooden structure.
The type of wood buildings they're making nowadays don't burn very easy. (not talking about timber framed houses like the US, but the kind used for taller buildings such as this article). They take wood- cut it in strips, arrange the strips in alternating directions (for added strength) and then glue them together with a fireproof glue.
They're actually more fire-safe than steel buildings. Steel will melt or lose strength with fire (as in 9/11 twin towers)- the modern timber buildings resist fire at higher temperatures than it takes for steel to lose integrity.
"That's the way to do it" - Punch
How long can a concrete and steel building last?
How long do even well engineered wooden structures last before succumbing to rot or burning down?
Well... There are wood buildings that are 1,500 years old. A properly taken care of wood building can last a long time. Wood doesn't rot if it is not exposed to water. The secret is proper waterproofing. As for fire, the modern wood buildings use flame retardant glue and are safer than steel at high temperatures.
Wood is also more earthquake resistant because they sway easier. Wood is more resistant to wind damage.
"That's the way to do it" - Punch
You're on the right track to some of the "devil in the details".
Soft woods like pine grow quick, but the wood is, you know, soft. Wouldn't want to live in a skyscraper made of that!
Calling pine a soft wood, and implying that it wouldn't serve well in a structural sense, is perpetuating a myth. SPFs (spruce, pine, fir) are highly regarded for their structural properties. Douglas fir, Southern Yellow Pine, Sitka Spruce, Hemlock...all have excellent MOE/MOR ratings, while yes, having low Janka Hardness ratings. Along with time-to-yield and price, these structural properties are why SPFs rule the US stick-built construction supply.
AFAIK, the hardier the wood, the longer it takes for the tree to grow. That means a long-term investment in your re-planting, and a lot can happen to your plot of re-planted little sprouts (bugs, deer, fires, suburban sprawl, drunk kids on ATV's, massive natural gas deposits) while you wait the lifetime or two for your trees to grow to full size.
Harder wood trees, do "generally" take longer to grow. However, today's new-growth trees pale in comparison to the mostly gone old-growth trees from a properties comparison. The hardness may be there, but their MOE, MOR, and density are usually lower, and their stability and durability are much more volatile. But, again, those are generalities. The science behind wood is quite fascinating; much more in depth than I imagined when I got into woodworking.
The Wood Database is a great resource.
On top of that, there is a class of concrete that actually ABSORBS CO2 of its surroundings.
Yes, there is such a concrete. It is very expensive and no one would ever consider using it in a large project. It will come up once in a while as a show house where people want to demonstrate a "green" future construction. They often look very posh, will claim having a very small (or even negative) carbon footprint, but very little will be said about how much it costs or if there is any study on the building meeting the CO2 output claims.
I had a conversation with a professor that was studying a way to absorb CO2 from the air by mining basalt and spreading it out over cropland. The claim was the the lime content in the basalt would be a nutrient for the crops and bind with CO2 in the soil. I asked if this would also be a good replacement for current sources of lime used in cement, he said it would. However, the energy requirements of mining this basalt would be much higher than current lime. Current lime is made by mining the much softer limestone (still a hard rock but easier to mine than the granite-like basalt) and "cooking" the limestone in furnaces to drive off the CO2 in the mineral, creating lime. For the mining of basalt to make sense we'd need an energy source that is quite energy dense, works day and night (because once a mine opens they want to keep going), is obviously low in CO2 output, and is cheap enough that it can compete with current lime production. What could that be?
These CO2 absorbing cements are typically made with naturally weathered basalt "sand". This is not very common as the lime will wash out over time if there is any rain. It is very dense so it's not going to be cheap to ship anywhere. As such this lime rich sand exists in just a few desert valleys in the USA. I'm sure it can be found in many other places in the world but the only sources of this in the USA are out in the Rocky Mountains. The basalt rock though is everywhere, it's probably under your feet right now, wherever you are reading this. More accessible outcroppings are quite common.
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I don't think you quite understand how fire works. Anything hot enough to melt steel will cause the wood to outgas its volatiles and add more fuel. Neither situation has a happy ending for the building.
How many years does it take for a newly planted tree to get back to the same size as the one cut down, and therefore consume the original amount of CO2? Decades?
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Driving a nail into a slab of wood requires a lot less energy than driving one into concrete
Seems like a desperate attempt at coming up with advantages... Does the energy of driving a nail into concrete really have some measurable impact? How many nails are driven into concrete in modern buildings?
Just to reinforce dj's point - hardness and strength are two completely different engineering qualities and usually have very little to do with each other. Aluminum for example is both fairly soft (the surface deforms readily in response to concentrated pressure) and fairly strong (in bulk it can withstand fairly impressive compression and tensile pressures)
In addition, hardness does tend to correlate with another, far less attractive quality: brittleness. The more rigid something is, the less it can temporarily deform in response to sudden stresses, which causes much higher spikes in the forces involved, and a much greater chance of breakage. Glass is actually very strong, but also very hard, and any sudden impact causes it to shatter. Oak has a similar weakness - it's not nearly as brittle, but an equivalent strength worth of SPF will survive considerably more abuse.
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It doesn't have to get to the same size to consume the same CO2 since the process of growing actually sequesters CO2
Sand and sandstone are literally the most abundant materials on the Earth's crust. No one's running out.
Of course concrete burns - even diamond burns.
More relevant to the low temperatures in your average building fire - concrete rapidly cracks and weakens in response to heat, while even without fire resistant treatments wood forms a layer of insulating protective char.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
In TFA it mentions that they come prefab in panels. A panel goes bad somehow, pop a new one on. Also, I wouldn't lay money on the laminate rotting easily.
You know it's gonna happen..
Concrete sequesters CO2 as it cures. That was what tripped up Biosphere 2; the relatively new concrete absorbed CO2 out of the atmosphere so the plants didn't have any to recycle into O2.
Got Wood?
Time between harvests on most "farmed" forests average 25-30 years. Might be some with faster growing tree, but even that is about 15 years.
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Wood is a really scarce resource. What are the French going to do, cut down even more trees to build tall buildings? Trees are a necessary part of the ecosystem as they do big things like help to reduce carbon dioxide and they provide shade. So cutting down trees to save the environment is like fucking for virginity.
yep, NYC's study of their trees is the most interesting thing I've read on this. https://www.nycgovparks.org/su...
Now I'm not the original guy but I think it's a choice of words here. Some of the newest treated wood ignites at 500C. Now steel won't melt at that temperature, not even close, but at 550C it loses 50% of its strength. So I sort of get where guy is coming from but yeah, it's an iffy argument. However, I think we can all agree that at either temperature, no one is going to exist very long. That said, I'm not sure about France's standards but I would assume that the level of planning that has to go into the fire suppression system before the blueprints are okayed has to be dizzying to say the least. However, I don't know the linked article is really shallow on information and I'm at work so I don't have the time to look it up.
consume the original amount of CO2
The CO2 is trapped in the cut down tree. So long as the wood isn't burned or rotting away, the CO2 is sequestered inside the frame of the house or building or whatever. Same goes for if you take a chopped down tree and get it to sink in a body of water. That's a carbon sink quite literally. Anytime you prevent wood from burning or being decomposed, that removes carbon from the atmosphere. Now the act of cutting the wood does release some CO2 gas, not in just the thing that's cutting the wood, but in the actual cutting.
Sure, all commonly used cements used in concrete will absorb CO2 over time. Perhaps I misunderstood the original claim but the implication I got was that it absorbed more than that was used to create it. The lime in cement will slowly turn to limestone as it absorbs CO2 from the air, but this will be no more CO2 than what was cooked out of it after being mined from limestone.
If people want to get CO2 negative cement that's actually affordable then they should to do as that professor proposed, use nuclear power and mine basalt for its lime content.
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"wood is lauded for its smaller environmental footprint and the speed with which buildings can be assembled"
This is something only someone very bad at math would say, or someone with a bias or agenda.
I do sustainable logging so you would think my bias is towards wood but I built my house, farm buildings and USDA/State inspectable butcher shop out of concrete.
The reason is that concrete has a far lower carbon footprint, lasts far longer, makes for far more energy efficient buildings and at lower costs. Both the short term and long term cost of my buildings are lower because of my use of stone -concrete is almost entirely stone plus a small amount of cement.
Wooden buildings don't last as long, don't have the build tin thermal mass of masonry (concrete) and cost more as well as actually having a higher carbon footprint.
Anyone who claims otherwise is hoodwinking you with their agenda.
Show me the standing wood building on Barbuda. On the otherhand using concrete and steel one can easily build a building that will withstand a category 5 hurricane unscathed.
But the CO2 in the building is relatively sequestered too.
If 20 year old growth is cut to make a building that lasts 30, that's net extra sequestration.
once equilibrium is reached (buildings taken down vs trees grown) there is more overall sequestered CO2 than if steel was used.
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The production of cement, one of the main ingredients in concrete, generates an estimated 5 percent of the world's carbon emissions. Trees, in contrast, capture CO2, helping offset emissions produced by a typical building process.
It sounds like dead trees aren't such a bad idea after all.
The idea can be carried forward to things like books. Why read obsolete and impermanet ebooks when you can, for often the same price, get a book printed on paper? The paper book encourages tree production, which captures CO2, helping offset emissions produced by server farms and the factories producing ebook readers.
You don't rate a fire-resistant structure by its ability to sit baking indefinitely at a certain temperature, but by the number of minutes or hours it provides safety while people evacuate and/or extinguish the fire. And once you have a fire-safe structure that doesn't collapse and compromise its egress paths, you worry about fire safety of the building which includes ventilation, fire suppression, and materials to avoid asphyxiating the occupants in a poison gas chamber.
Thick timber chars on the outside when exposed to extreme heat. This is almost a self-healing, temporary insulation to slow the heat transfer to the rest of the wood on the inside of the timber. That's why a big log in your fireplace burns for many hours and doesn't immediately explode your house from over-pressure. The timber continues to be able to bear most of its rated load while this outer surface is burning.
Meanwhile, steel will quickly conduct heat throughout and soften until it suffers a load failure, long before it has reached its liquid phase. The twin towers didn't collapse because the steel was solid one minute and liquid the next. It collapsed because it became soft enough for large horizontal spans to sag and separate from their supports, fall a whole story, and exceed the load-bearing capability of the level below.
Steel structural members have to have fire insulating layers to mitigate this type of problem and allow people to escape. The violence of the plane impacts in the twin towers destroyed egress routes, trapping people. It also tore away a lot of the fire insulation (asbestos) meant to protect structural steel, so the collapse happened sooner than it might have in a typical fire.
"Yes there is such concrete. It is very expensive..."
So are various high-strength mixes used in high rise construction. And while current processes make it unfeasible outside of academic, experimental testing, there's no guarantee that this will remain that way, as testing is ongoing.
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"Wood is more resistant to wind damage."
Tell that to a hurricane or a tornado.
Down in areas where this sort of thing is problematic, consistently, the only houses that generally survive with more than cosmetic damage are concrete structures.
Also, if you're worried about concrete structures being able to move, there are additives which improve can increase a building's ability to sway and withstand cracking.
And, at the same time, there are building techniques for isolating such a structure to minimize sway.
Also, you use the term "properly taken care of". Take your 1500 year old example. Now, how many SIMILAR buildings of the same era are still standing.
THEN tell me about percentages of buildings that would properly be maintained...
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Cross Laminated Timber (CLT), which is what the article is talking about, and Oriented Strand Board (OSB) are very different products. CLT is more like plywood, but 5 inches thick with 1-inch plys.
As an example, Stadthaus / Murray Grove in London is a 9 story building of CLT, with no other structural materials. The walls, floors, lift shafts, etc. are all entirely CLT. I'm sure CLT is used in some US buildings, but I doubt it's very common (yet).
And how many "sibiling" structures in the area are the same age.
Sure. If you take extremely good care of a building it'll last a lot longer.
Do you REALLY expect this sort of in-depth care from modern society ON EVERY BUILDING? And do you expect the kind of care in construction from modern "Throw it up FAST!" builders?
I invite you to sample multiple seasons of the television productions of one Canadian by the name of Mike Holmes.
Not saying it CAN'T be done. Simply that concrete is just a superior building material in terms of ease of use, longevity (the world's oldest concrete structure is sneaking up on its 1900th birthday) and maintenance.
Right now, the AVERAGE rated lifetime of a stick-built building is 50 years.
The average rated lifetime of a WELL BUILT stick-built building is 150 years.
The average rated lifetime of a concrete building is 200 years.
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If you're lucky. In many places they don't bother to replant unless the government forces them to, in which case they complain about excessive regulations hurting their get-rich-quick schemes. Even int he US the timber industry prefers clear cutting as it keeps the expenses low.
Not saying it CAN'T be done. Simply that concrete is just a superior building material in terms of ease of use, longevity (the world's oldest concrete structure is sneaking up on its 1900th birthday) and maintenance.
It'd be nice if we hadn't forgotten how to make that kind of cement mix.
My house is over a hundred years old, the concrete foundation is crumbling in places. Other than one corner where some idiots hadn't properly sealed the new porch, the wood frame is doing fine.
On top of wood being flammable, termites don't eat concrete ...just saying ...
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And after those US companies clear cut a tract of land they immediately replant it so that in 15 - 20 years they can clear cut it again.
I've planted hundreds of thousands of trees. How many have you planted?
The place was always subject to earthquakes, so during the nineteenth century buildings were made of wood. It was found that New Zealand kauri pine was an ideal material: it was strong enough to build high, grew straight and knot-free for hundreds of feet, and was flexible enough to resist the strongest earthquakes. By the end of the century, the entire city was made of kauri.
Two problems arose. NZ realized that a kauri takes a thousand years to grow, and that their export rate was totally unsustainable. They stopped exporting it just in time to save the species. One day in 1906, the other problem became evident: kauri was earthquake-proof, but not fireproof.
You're on the right track to some of the "devil in the details".
Soft woods like pine grow quick, but the wood is, you know, soft. Wouldn't want to live in a skyscraper made of that!
Calling pine a soft wood, and implying that it wouldn't serve well in a structural sense, is perpetuating a myth. SPFs (spruce, pine, fir) are highly regarded for their structural properties. Douglas fir, Southern Yellow Pine, Sitka Spruce, Hemlock...all have excellent MOE/MOR ratings, while yes, having low Janka Hardness ratings. Along with time-to-yield and price, these structural properties are why SPFs rule the US stick-built construction supply.
Especially the old growth stuff like what my 1950's house is made of. I have no problem driving nails and screws into recently made pine studs but these old original ones in my house tend to break drill bits if I'm not careful and pilot holes are needed for even the smallest of nails.
This is certainly true, but the but comes from the Boston area where I live and not one, not two, but three mid-sized (~10 storey) wood-framed structures burned last summer while under construction without having all of the fire suppression systems installed yet and a major fire in a densely built neighborhood of woodframed two-storey structures about a year ago. Apples and oranges to some extent, but something about building big and dense with wood sets off alarm bells.
I believe the preferred troll-spelling is 'AmeriKKKa,' or at least that's what I recall from BHO's favorite pastor.
Which is not necessarily a good way to do it. It would act similar to a wildfire, in that for a few years there is bad erosion. It also has the same type of tree in that plot instead of a mix, and so forth. Especially if this is a national forest, loggers should be required to do what's best for the forest, it's not their land after all. Yes, it is much harder to pick just some of the tallest trees and dead trees, because once they've built the logging road into a patch they want to cut it all down to justify the expense.
Not saying it CAN'T be done. Simply that concrete is just a superior building material in terms of ease of use, longevity (the world's oldest concrete structure is sneaking up on its 1900th birthday) and maintenance.
It'd be nice if we hadn't forgotten how to make that kind of cement mix. My house is over a hundred years old, the concrete foundation is crumbling in places. Other than one corner where some idiots hadn't properly sealed the new porch, the wood frame is doing fine.
Actually, I hear we recently rediscovered it--and it's basically 'use saltwater.' Sometimes, it's the stupidly simple things... (The salt changes the structure of the concrete, I suspect somebody more interested in concrete can find the article.)
Actually we know exactly how the Pantheon was built and the type of concrete used.
And yes, we can reproduce it today.
Chas - The one, the only.
THANK GOD!!!
I don't think you quite understand how fire works. Anything hot enough to melt steel will cause the wood to outgas its volatiles and add more fuel. Neither situation has a happy ending for the building.
You don't have to melt steel for it to lose integrity. Steel becomes weak and pliable and collapses long before it melts.
"That's the way to do it" - Punch
You actually think that houses in the US don't make use of OSB? You actually think that we don't use ISO adhesives?
Ignorance abounds. All it would take is 30 seconds on any construction site, or even seeing one picture of a construction site, or browsing any construction goods store like Lowes or Home Depot.
OSB is used in flooring and roofing. It is not used to construct wall frames or supporting structures.
"That's the way to do it" - Punch
Have you ever seen a wooden ship or building that's burnt but the main beams are still mostly intact?
It's called ablation. Educate yourself.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
During the day, they store sugar. At night, they burn it. When growing, they bind it up as cellulose (material) or starch (storage).
Leaves fall, rot, and release CO2 as bugs and bacteria burn them for oxygen. Fruit falls and rots, although new plants mean new growth. These things don't sequester carbon for very long. Non-fruiting trees sequester carbon for a day when they're not budding new leaves.
Basically, if it's not forming stable mass, it's not sequestering carbon.
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That was my point - they come prefab in panels. What happens when the tech changes and those panels are no longer made? In the future, how will one modify the current prefab panels to fit them into a 50 year old prefab structure if the prefab sizes are different?
Structurally, how does one incorporate a different panel with different physical properties possibly modified to fit into existing prefab construction? Remember, we're not talking about 2 story houses here - we're talking skyscrapers. Sure, one different panel won't make it fall down, but at what point do repairs reach the point where you need a structural engineer on site?
Pure wood is easy, because you can just cut it to fit. And how you stick wood to wood is pretty well understood. Sticking a wood laminate to a 50 year old other type of wood laminate I'm guessing is slightly more complicated.
And no, laminate probably won't rot. But will the binder deteriorate over time? Will it become brittle after 50 years? We understand wood extremely well, and when it fails it's easy to fix. This could be stunningly good multi-century technology, or 50 years from now we may need to be tearing them down, because we've moved away from the technology used to build them and can't repair them.
Velociraptor = Distiraptor / Timeraptor
Still very rare in the US. But starting to get some use. Portland will get an 11 story CLT building.
http://www.oregonlive.com/busi...
Russian wood is not very common on the Western European market.
Plenty of Russian wood on PornHub.
To have a right to do a thing is not at all the same as to be right in doing it
I don't think you quite understand how steel works. Steel gets dramatically weaker as it gets hotter. At a temperature of merely "too hot to hold", it's already lost a measurable amount of strength. By the time you hit the ignition point of wood, your typical structural steel will have lost about half its strength (and will stretch like taffy, making materials testing an exciting proposition).
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
seawater and volcanic ash
http://www.popularmechanics.co...
Using wood for buildings is good for the environment. If you believe that steel and concrete is better then I'll ask you to show me your math
Everything is a trade-off. Which stands up to a hurricane better? Wood or steel/concrete? Which is more flame retardant? Ever read the children's story of the 3 Little Pigs?
We'll make great pets
It would be ironic if you write that from a deforestated suburb!
This is a very poor argument. Where I am located and my choices for where to live are independent of this logical fact. It makes no difference. It is independent of me. This is probably hard to grasp for the narcissists around here.
We'll make great pets
That article claims that concrete reabsorbs up to half the CO2 that was used to make it, I'd hardly classify it as "scrubbing CO2". (And, by comparison, when you "make wood", you grow a tree, cut it down, and grow another tree in its place, so wood really does constitute a CO2 sink.)
Making concrete is actually one of the worst carbon dioxide production systems out there. It's horrible stuff. If there are ways to make wood do what we need it to, we really need to switch back to it.
You are not alone. This is not normal. None of this is normal.
That article claims that concrete reabsorbs up to half the CO2 that was used to make it, I'd hardly classify it as "scrubbing CO2"
That's even just normal concrete - there is concrete that has been developed that really does scrub CO2, and a lot more of it.
And, by comparison, when you "make wood", you grow a tree, cut it down, and grow another tree in its place
Yes but as I said you are expending a LOT of energy, and a lot of chemicals, on maintenance of that wood - even in dry climates you can't simply leave wood out and untreated. Concrete requires much less maintenance, so in balance I'm not sure the wooden structures are any better from an environmental standpoint. However I would say wood (to me anyway) sure does look a lot nicer generally...
Making concrete is actually one of the worst carbon dioxide production systems out there.
Look into wood treatment products and the chemicals involved, I would argue they are much worse in terms of sheer pollution (which you should care about more than CO2).
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Customer: "I need a nanofabricated, self-assembling, self-perpetuating 300 ft tall photo-voltaic tower. For free."
Human Contractor: "Are you crazy? Even if that technology existed, it would cost a fortune."
Nature: "Text me."
Concrete actually gets harder over time. It's a fantastic material that we should be using more not just in construction.