Michael Green: Why we should build wooden skyscrapers
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- Опубликовано: 8 июл 2013
- Building a skyscraper? Forget about steel and concrete, says architect Michael Green, and build it out of ... wood. As he details in this intriguing talk, it's not only possible to build safe wooden structures up to 30 stories tall (and, he hopes, higher), it's necessary.
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This video made me fall in love with timber structures, I am a Structure Engineer from Brazil and now a professor of timber structures, I also want to do my Ph.D on this area to build a better and sustainable world.
JuIiana Remor Amazing. I will love to see that vision within the near future. Goodluck to you.
Maybe you should search for Erwin Thoma and Austrian ranger now have a company for wooden buildings
During the video they talked about wood buildings being fire resistant. There are several examples throughout history where buildings and siege equipment were used to make war equipment fire proof I think that if we looked into those solutions than we would be able to fix those problems.
Sure! Also large wooden beams are able to retain their strength even longer than steel in high temperatures. Steel will eventually soften and start to bend, while the wooden beam is still just a bit charred on the surface. So at least the house doesn't collapse as quickly.
Dont forget Bamboo! this material is growing a lot faster than wood and pretty strong too
Isnt bamboo wood?
It's a very fast growing wood substance making it the perfect tree substitute.
Technically bamboo is a type of grass, however it has many irregularities and cannot be used on a scale as structural timber. But small structures can be made of bamboo, the material also can be used as a reinforcement substitute in concrete
@@L0opyProductions I've seen massive structures made with bamboo.
@@orishejuukuedojor2736 It's a type of grass, actually.
wood is a great insulator as well therefore, it will be wise to build more wooden skyscarpers in colder regions of the world.
In addition, warm/hot climate region housing often uses more energy than those of cold climate.
Like everyone else, I was (and am) concerned about fire - as soon as "wooden building" is mentioned, that thought is right there in your head. But he addressed that.
What wasn't addressed is something most Australians are intimately familiar with: TERMITES! OK, so those are not unique to us - the UK has woodworm that also ruins timber structures - but most countries don't have 7' high termite mounds. There's a really good reason a lot of Aus homes are now built with steel frames. You can treat timber with toxic chemicals to stop them, of course, but then you have a toxic building, you've created a big problem with disposing of the material when you pull it down, and the previously-mentioned fire problem has just become a toxic chemical spill.
Whats that mate? The creepy crawly things that want us all dead?
That's not a problem. I studied wood structures in college (civil engineering) and I'm currently doing my graduation thesis about laminated wooden structures, so let me tell you that for every problem you imagen this could have, there's a treatment on the factory for it.
+Rodri Btz Such as?
what about hurricanes?
Rodri Btz oh, huh. Laminated wood, hm.
Great idea, nice speech. I really do hope that this will become reality.
The Japanese built with wood 1000 years ago without glue, screws, nails or magic. Through craftsmanship carved wood with precision and skill still holds buildings from 1000 years ago, even in a seismic area like japan. I'd love to see my kids children life in a save wood house!
+JayFolipurba As a person who studied, does, and loves Japanese woodworking going back to the late 70s, I have to say that the Japanese tradition is not that different from the western one. In the west we made plenty of framed buildings or furniture without nails or glue, using just joinery. The japanese avoid the diagonal brace, perhaps due to seizmic needs, but it makes their structures unfathomably inefficient. By the way, the Japanese, just like us use nails extensively, that just isn't the part you see when making shoji, or timber frames, any more than you would see that in western structures of a similar type. Western frame and panel doors are sometimes held together with just wedges, as an example. But the Japanese still need to hold shingles on a roof, and the carpenter's tool boxes were nailed together. They saved the fancy joinery for the paid work.
here, i dare to squeeze in Korean architecture as well. historically speaking yes, many woodworkings around the world in old times used joinery and wooden pegs. sometimes natural glue from boiled fish was used which expanded and contracted similar rate of wood.
old korean architecture made separated column base parts so you can remove and replace them whenever there is any damage without having the entire building collapsing.
and the oldest method of heating, ondol, is now one of the most popular, efficient, and healthiest methods around the world.
there are so many things we simply cannot ignore but lots of people wont look into it thinking its 'outdated.'
why cant we amplify its core with modern technology?
LOL when you realized most were rebuild
Wood is actually a pretty easily renewable resource and as he said, the population is quickly urbanizing. This all makes sense.
I think to get the most bang for the buck, a composite material would be best though. I'm no engineer, but I'm thinking a laminate of wood with a few thin steel or plastic layers incorporated for extra strength?
Check out Brock Commons or the Earth Sciences Building at UBC Vancouver, that might answer some of your questions about added structural integrity :)
Thing is joining wood and steel is difficult. A joinery is only as strong as the weakest material. A joinery of steel and wood would be weak but wood and wood joinery is strong. It's like to like material when joining different structural members are needed.
That was cool, definitely my favorite building material
wow awesome! I didnt think about this but it makes total sense. Wish you showed us some of the construction panels in pictures.
Spot on! Wood is a really versatile material and the newest technologies are causing a rethink on how we think about this wonder of nature!
Excellent lesson!
Thanks a lot!
Awesome, thank you for correcting myself on that!
I liked the buildings they are truely calming and natural looking :)
Sounds good. Just needs some more attention and planning but it should work!
I wish this talk could go on longer. I'm interested in how they would tackle the other issues.
We have been marketing Vulcan timber for the last 6 years in India and it has changed my belief system about wood completely. This new technology handles the traditional challenges with timber - movement, high maintenance and termites/fungal decay. And that too in a sustainable manner. When you see on the ground projects where natural timber is performing very differently, in the right way, it forces you to change how you think!
That was my exact question. Mr. Green talks about wood taking carbon out of the environment, but trees don't exactly grow fast, and I'm not a fan of logging. Given that 1 acre of hemp is roughly equivalent to 4 acres of trees in fiber. Could you make this composite material out of hemp? I want to live in a weed building - and I'm sure up north from Vancouver in Kelowna they have weed that grows at least a few storys tall
"Do you respect wood? Ya gotta respect the wood". -- Larry David, Curb YE
I've followed the idea of building from wood but, I haven't heard what kind of trees? What are the trees used the most?
So many considerations left out during the talk.
thanks! that explains it very well
On 3.15 you are talking about the 3% and 5% steel and concrete CO2 production, is there a source where I can find this? I'm doing research to the wooden structures in buildings and want to compare them with a steel alternative
The comparisons are very interesting between wood, steel, and concrete. Concrete's carbon contribution is inherent when it cures. But steel's contribution is primarily based on energy production (that is, a lot of electricity is used to produce structural steel). As we move increasingly to renewable energy sources, steel's CO2 production diminishes. In addition, when looking at the wood numbers, the wood industry tends to skip the environmental impact of demolishing a wood building (some wood conceivably could be reused but most of it is either incinerated or landfill -- both of which have a bad CO2 impact. The wood industry also conveniently ignores the wood waste at the point of harvest -- this can represent a significant increase in wood's CO2 impact. There are a lot of other issues that also should be considered. For a more in-depth discussion, visit www.aisc.org/discover and download the whitepaper.
he addresses this in the video...Wood, especially large members, take very long to burn. Steel isnt as strong as you think; it turns to spaghetti under fire conditions.
Nicely put.
Really like this guy's presentation.
Also, people need homes, not apartment units.
very good, thank you.
At first I was skeptical, but he's a great presenter!
I live in a 90 year old 2 story house. Half of it is wood, and I love it.
We had a speaker come in to our training facility (carpenters local 27) regarding this method of assembly in the greater Toronto area.
I look forward to the advances in material science to come. It will be very exciting.
anyone remember the Chicago fires? we go wide spread like this and fires become a MAJOR problem again. reason why arson had the death penalty back in the day and even now it's considered felony.
Yeah I'm sure he went on TED and gave this big speech without having thought about wind and plate tectonics, and discussing such matters with civil engineers.
The problem with wood is that wood burns. When you have a single or double story building the fire risk is very low as the majority of these buildings are unoccupied when they burn down and evacuation is very easy.
If you make a skyscraper out of wood they you have a majestic chimney that will go up like a roman candle. In addition said roman candle will be a danger to nearby wooden buildings.
Solve the fire problem and we can build wooden buildings in cities.
Yes I suppose they could do that. I mean, I did a course in wood construction and I honestly do love the idea of wood structures. I guess this all comes down to the architecture.
Hey which uni did you take this course I was hoping to a apply for a course like this if possible in the summer would really appreciate a recommendation. thanks in advance viewers!
with modern applications of tuned mass dampers the oscillation loading effects can be diminished considerably. This will most likely not present a design issue.
there are 2 questions that he forgot to address:
1-is wood structurally sound and able to face strong winds, earthquakes, and heavy loads?
2- what about moisture and mold? i think even if it was layered and protected with materials, this can be fatal since it's affecting the main structure of a building.
the idea isn't bad but it definitely needs a lot of refining.
That's true; I've heard of banks foreclosing on people's houses (kicking them out) even when they don't technically have the papers proving they own it, and *then* having to pay tons of money on upkeep because they can't sell them.
That's less an issue of environmentalism and more an issue of injustice, but it IS extremely wasteful and should be checked. It doesn't necessarily mean we should stop building new houses.
Span:Beam Depth ratio plz! ^^
I want to start on a model asap
im a termite and i like this idea.
Wood does have more flexibility, and a descent average strength but what i am worried about is the variable strengths in wood. Wood is a product of nature and it is a well known fact that nature is random, i just hope we don't push the limits to far and cause a failure in a skyscraper.
It would be interesting to see some statistics about forestry needs against housing needs in a scenario of high deployment of wooden skyscrapers. So, it takes less than quarter of an hour for N. American forests to build one 18-story skyscraper. How much wood can we reasonably produce and how many people reasonably house. Where?
Very interesting lecture :)
This is a real issue...believe it or not i have been
thinking about this stuff since 2015 after visit form a site situated at hilly area's of Bangladesh....and i want to add up something more...We should really think about limited measurable cubic quantity of top soil, which are using for making bricks" .. the most ironic fact with all the latest technology, we can not create just 1 cubic soil or stone.....on the other hand we can create UNLIMITED cubic wood for our need by limited knowledge and proper planning ......thanks to Michael for bringing this issue upfront.....
There are a large number of hemp-based building materials and products, and yes, it is totally banned in the Land of the Free (tm). There is hemp-crete (with the fibers acting as rebar and the chaff acting as insulation); hemp-based lumber (compressed/glued fibers) and hemp plastic (hemp seeds contain lots of oil). Yes, they are heavily treated and processed, but no more than many wood products (e.g. fiberboard) and grows many many times faster and is much easier to harvest.
I've always thought going up was the wrong idea anyway... why not go down? It makes it easier to maintain heat and cooling in disparate climates, it's less pressing on the ecosystems because there is more of an albedo effect if we can replace space filed with skyscrapers with greenery or other cooling materials, plus you have more versatility with material usage.
With regards to the carbon footprint, he showed us the carbon effect from concrete in the comparison, but did he consider the carbon footprint of the wood from origin to mill to factory to site in that equation? He mentions its stored capacity, but does not mention about the carbon output during the production of the panels, members etc.
Bamboo and carbon fiber would be interesting as well.
Ideally, if we're talking centuries scale, roman-style concrete coating an alternate material.
I'd be concerned about building lifetime and the binding/coating on the wood in order to make those skyscrapers.
Still think this should go forward, because having competitive technologies encourages the creation of completely new solutions.
GENIUS
I was thinking the same thing!
I agree. I'm sure there are fire retardant coatings and baths for lumber, but can these massive building blocks use those and how effective will they be? He says "they burn slow, so it's okay!" I disagree, our skyscrapers are made of metal and concrete, which do not burn. It's not the building material that starts the fire, it's what's put inside. You're basically constructing a log-cabin style fireplace with kindling and tender inside. The fire problem is not fixed.
Its not about solving the problem, its about contributing to the solution where ever we can. Its going to take change in all areas big industry to conquer that problem.
awesome, i want to contribute building green buildings like these
Good point.
I think this is a great issue, but in a tropical country like mine (Venezuela) we don't need chimneys at all because of the high temperature.
This guy is a great speaker.
good presentation
1:16 I've seen how people touch, the wood... lost it xD
I'm amazed he actually convinced me that wood is a viable material for mass construction. Kudos
Inspiring talk.
awesome
That is not really an issue, in current building codes for gauged timber (2x4 etc), wood is derated to 5% of it's typical strength, rightly so, to account for the worst-case defect (knots etc), by laminating 10s, to 1000s of individual sections to form a glulam beam, defects are encapsulated and delocalised, allowing you to build closer to the bulk strength of the timber. You can think of it like rope, the whole is greater than the sum of the parts.
fully agree with You!
I would love to see these buildings in Vancouver. They sure beat the depressing concrete and glass buildings here.
I build houses on the beaches of North Carolina every day. Some flooding and a lost shingle or two is about the extent of most damage.
Those aren't the actual issues. Fireproofing is relatively easy; but it isn't easy making them strong, stable, durable, and uniform enough in those characteristics to reliably plan out a massive project with them. Imagine if one piece would rot out in 20 years, but another would last for 50. If they don't know which piece will last, that means an expensive building would fail along its weakest point, making it a risky choice for building with.
Companies that maintain these buildings will have a constant flow of cash to renew the buildings
how do you keep the wood from rotting?
lam
This is very interesting, and I bet all those obvious questions (deforestation, durability, etc) are being taken into account by specialists. There's one big mistake in his idea though, and that is the misconception of the housing problem having to do with the existing number of houses. The day there's not a single empty house left then we should start worrying about building new ones.
10:25 when he is talking about the first skyscraper, is he talking about the building in the center of the photograph, or the one to the left of it :P
Which is why they used young logs that haven't aged enough to have lots of variability to make "mass timber panels" which increases strength and decreases the problem of variability of strength even further.
이거 혹시 번역되어있는거 있나요..?
Indeed. Steel burns, melts and collapses. Wood buildings burn, char, and in many instances will remain standing after burnout, or at least longer than steel.
You just answered yourself, in the world we're living, is a totally idealistic idea. There's a reason why skyscrapers are not done with wood, besides the fact that wood is not a fitting material for high buildings. This kind of guys are the ones who give architects a bad name, he would be perfect as salesman though.
You're right about that, but even locally that problem exists... In Spain (the closest example I can think of) people are getting kicked out of their houses and ending up on the street, while buildings remain empty. I think he's got a good idea, it's just that more houses aren't the solution for the housing problem.
Striking and so true
Termites I believe aren't much of an issue since he's talking about a manufactured product from wood and not just logs in particular. They could easily pressure treat it with the protection needed to ward off termites, but the warranty is good for 10 years I think (armourwood is an example).
bang on!
It depends upon the Code adopted by the local jurisdiction, but recent editions of both the IBC and NFPA 101 require new high-rise buildings to be equipped with a sprinkler system and an automatic fire detection/alarm system with 2-way communication capabilities. With the advances in fire detection and suppression since the Great Chicago Fire of 1871, the thought of building collapse from fire does not concern me. I'm more concerned about impact resistance in high profile areas, such as NYC.
Revolutionary ... wow!
saw a vid about hemp being much better at storing carbon than wood. also grows much faster.
you can do the same with steal and concrete. btw the core of a skyscraper is usually used for elevators, staircases, installations. most of that stuff can't be accessed from within the floor space you can buy.
e a manutençao ?
Carbon is the building block of trees, aka they convert all CO2 into sugars and other molecules, that create the whole tree. When a tree dies, it actually releases some of this carbon, but most of it remains locked up in the wood. Thus millions of years later this carbon can be released when the wood is burned as coal. So the wood doesn't clean CO2 after it dies, only while it is alive.
As an engineer I believe building with wood is a good idea for aesthetic. It's important to note why the speaker is trying to convince you that building with wood is a good idea. He likes the way it looks and the way people think about it, hence aesthetics. As an architect this is his job and he seems to be doing it well. However, we cannot delude ourselves about the use of wood as a major method of reducing global carbon emissions or any other global issues.
I'm mainly concerned with costs. Is the cost of wood low enough to compete with concrete and steel? Obviously 2x4s are cheap, but what about all the processing required to make these beams structurally sound?
What about longevity, how would we make them last?
There are a few missing facts here. Only a small fraction of the carbon from logged forest is stored in wooden buildings. A much larger fraction of the carbon from logged forests is transferred to the atmosphere.
for an alternative perspective, google: forest carbon climate slideshare
9:31
Can anybody tell me how is wood reducing emission than in case of concrete?
Saumitra Shrivastava concrete produces more Co2 in its production. Trees lock co2 from the air into the wood
I was confused as well. What he's saying our two options are use wood, and soak up 3100 tonnes of CO2 or use concrete and emit 1200. So a +1200 vs -3100. The gap between those two numbers (not the sum) is 4300. So the difference between the choices is a 4300 tonne (4,300,000 kilograms) decision. The gap between the possible outcomes is 4300 tonnes of CO2.
Question would be how do these building act in different climates, for example where in summer you have + 20 degree Celsius and in winter it is - 20. Plus all the wind, rain, snow and other environmental things. I like the thought of this, but this needs more long run technical explanation, or can these buildings withstand all the climates we have around the world and still be safe. I'm guessing they are looking into this. I would be interested to know more.
Well, most houses in Finland are built out of wood and we have winters of -20 celcius and summers of +20 celcius. There are also a lot of new wooden apartment buildings cropping up all around Finland as well and our housing code is super strict. Actually if cities had more wooden buildings they would be cooler during summers since wood doesn't soak in the heat unlike concrete buildings.
Well yes, wooden buildings have been around for centuries. I am thinking more if his proposed concept would work in conditions like this. Because a small hut acts different from an apartment building and again with an sky scraper. I like this concept and that it offers so many possibilities.But still it would be interesting they built something like this in Finland, how it would react to the elements nature trows at it. Well then we can start the argument on - this works as better housing than what we used to have.
Of course glue is used but you have to put it into the right perspective. And I think they actually considered the fire threat if he already mentioned it. I'm not saying there are no problems but I honestly don't think fire is one of them as it is the most obvious and if he wants to seriously sell his concept, fire-safety is one of the most important things to address. If you wanna argue you should have something better, really - not saying it is perfect, it most likely isn't and has its cons.
What about the cost? How could these wood buildings solve the housing problem if they end up costing more than a concrete building? Besides that, what about the durability of these buildings, would that worth in a long-term?
Durability as the same, cost is £797/m2 for timber and £799/m2 for steel frame.
@@lindamizun7805 woods are not weather resistant. My house's rooftop made out of wood is now falling apart. 10 billions people will roam this planet. How many trees do we have to cut down then replant to sustain the constructions ???
that sounds really great, millions of extra trees grown on tree farms!
Just wondering what is Your suggestion from where to take the fertile ground plus water etc. for all these newly needed tree farms with millions of trees?
What would be more suitable: converting farm land which is today used to produce food plants, or converting any natural jungles, rain forests or other natural biodiversity places which would then be transformed to monocultural tree farms?
I do think that this is a good idea but there are some things that needs addressing. He actually talked about deforestation but does he really think that this model he proposed will actually reduce deforestation? We already have an enormous "wooden black market" specially in Brazil were people sell illegal wood to big companies telling them it's chopped in a legal area. That model to me only looks like another thing bad people would use to explore the illegal logging sites and therefore, increase deforestation.
Another question is: Will it resist the weather? We all know that many trees do resist rain but they have a hull to help it. Logged trees lose that essential part since they've been shopped and shaped into something else (ie.: the 2 by 4 block). So is it possible to give it a load of chemicals to make it as so it can resist for many years to come?
I'm not really convinced about the fire safety explanation he gave, and what about humidity and termites?
Interesting.
The carbon sequestration bit piqued my interest/smartassness. If you build a building out of wood, and it can trap carbon dioxide, won't it mostly just trap the carbon dioxide we exhale while occupying the building or is that rather miniscule compared to that wood's overall exposure to carbon dioxide in the air?
Overall, I think it's a great idea. Using natural resources for buildings is the way forward. In the end, I'm sure the environmental impact is far better than mining iron for steel and making concrete.
Yeah, I have to wonder also, but I suspect wood, even in the structural elements described would be at least as cheap as steel, but it is certainly a question that needs to be answered.
On an unrelated note, I wish more skyscrapers would be built so that we could fit everything in them and do away with transportation. With huge skyscrapers you could find everything you ever needed within a 10 block radius. You could walk everywhere and transportation would be taken for leisure. The air quality would be way better, and farms could be really close because we freed up space for them.