Michael Green: Why we should build wooden skyscrapers

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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[@juiianaremor8893]

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.

[@cooldog3014]

JuIiana Remor Amazing. I will love to see that vision within the near future. Goodluck to you.

[@CUBETechie]

Maybe you should search for Erwin Thoma and Austrian ranger now have a company for wooden buildings

[@TheThompson425]

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.

[@haijyvelho]

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.

[@solrac18619]

wood is a great insulator as well therefore, it will be wise to build more wooden skyscarpers in colder regions of the world.

[@juholaaksonen7455]

In addition, warm/hot climate region housing often uses more energy than those of cold climate.

[@Kyoooooog]

Dont forget Bamboo! this material is growing a lot faster than wood and pretty strong too

[@orishejuukuedojor2736]

Isnt bamboo wood?

[@nickilovesdogs8137]

It's a very fast growing wood substance making it the perfect tree substitute.

[@L0opyProductions]

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

[@orishejuukuedojor2736]

@@L0opyProductions I've seen massive structures made with bamboo.

[@patrik5123]

@@orishejuukuedojor2736 It's a type of grass, actually.

[@CyberiusT]

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.

[@LJLancaster]

Whats that mate? The creepy crawly things that want us all dead?

[@Rodriguito123456]

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.

[@77Night77Shade77]

+Rodri Btz Such as?

[@emmabila3480]

what about hurricanes?

[@naiknaik8812]

Rodri Btz oh, huh. Laminated wood, hm.

[@louisswanepoel1614]

Great idea, nice speech. I really do hope that this will become reality.

[@aion2177]

wow awesome! I didnt think about this but it makes total sense. Wish you showed us some of the construction panels in pictures.

[@satinderchawla3669]

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!

[@ThomasMVAX]

Excellent lesson! Thanks a lot!

[@DAVET0NE]

That was cool, definitely my favorite building material

[@spanfloors]

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!

[@JayFolipurba]

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!

[@HondoTrailside]

+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.

[@elee9056]

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?

[@sky-nf5tm]

LOL when you realized most were rebuild

[@sladkajes]

I liked the buildings they are truely calming and natural looking :)

[@masonkane5884]

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?

[@pandoratypography]

Check out Brock Commons or the Earth Sciences Building at UBC Vancouver, that might answer some of your questions about added structural integrity :)

[@agupta2k1]

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.

[@aboood578]

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.

[@FinallyGotATubeName]

Nicely put.

[@mckeighanjoshua]

Really like this guy's presentation.

[@fullfist]

thanks! that explains it very well

[@jampozbear]

Awesome, thank you for correcting myself on that!

[@MazeFrame]

Sounds good. Just needs some more attention and planning but it should work!

[@jackdan91]

I wish this talk could go on longer. I'm interested in how they would tackle the other issues.

[@imwithstupid086]

So many considerations left out during the talk.

[@mauricioecheverria3345]

We had a speaker come in to our training facility (carpenters local 27) regarding this method of assembly in the greater Toronto area.

[@fullfist]

very good, thank you.

[@TimesNuRoman]

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.

[@HiAdrian]

I look forward to the advances in material science to come. It will be very exciting.

[@khaledbenaida3532]

Very interesting lecture :)

[@becnicjac3]

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?

[@xapemanx]

good presentation

[@TheRichardlin23]

At first I was skeptical, but he's a great presenter!

[@davidhoggan5376]

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.

[@DaRealMidnight]

Inspiring talk.

[@Yibble100]

"Do you respect wood? Ya gotta respect the wood". -- Larry David, Curb YE

[@johnleeb]

Uncomfortable with mother nature controlling the patent? More likely that corporations can't patent it themselves and then demand lots of royalties! Until Monsanto develops a GM version that will be patented.

[@barthazewinkel2515]

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

[@scottmelnick7654]

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.

[@austininflorida]

Good point.

[@michaeljames1585]

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.

[@anikan865]

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!

[@DynamicUnreal]

This guy is a great speaker.

[@westerlySojourner]

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

[@michaelmcgovern7139]

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?

[@BOZ_11]

GENIUS

[@izrafeil]

awesome, i want to contribute building green buildings like these

[@u1b2]

im a termite and i like this idea.

[@JRPeyesatsne]

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.

[@fred08830]

Revolutionary ... wow!

[@Maddolis]

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.

[@michaeljohnston7958]

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.

[@amranhasan4020]

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.....

[@bangalorebobbel]

fully agree with You!

[@LyuLyuSt]

I live in a 90 year old 2 story house. Half of it is wood, and I love it.

[@erikwaanders8219]

Striking and so true

[@TnEEn]

Span:Beam Depth ratio plz! ^^ I want to start on a model asap

[@nantukoprime]

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.

[@MrKdnas]

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.

[@xguidroz1]

I was thinking the same thing!

[@Ausermac]

I'm amazed he actually convinced me that wood is a viable material for mass construction. Kudos

[@jbiasutti]

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.

[@imwithstupid086]

Also, people need homes, not apartment units.

[@Naglak2008]

awesome

[@Preator497]

with modern applications of tuned mass dampers the oscillation loading effects can be diminished considerably. This will most likely not present a design issue.

[@pdoylemi]

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.

[@mjss1984]

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).

[@bangalorebobbel]

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?

[@mjss1984]

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.

[@MrKdnas]

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.

[@noyansancar7767]

Sustainable material, if well managed environmentally. Plus, good heat insulation , naturally. Plus, absorbs moisture. i.e. very healthy especially in humid regions. Plus, a well designed CLT roof structure of a say, sports hall is safer than a steel roof even with fireproofing because in case of a fire timber may burn into charcoal but still maintains stability whereas steel tends to yield at at 1100 degrees centigrade. Noyan Sancar, Istanbul

[@metaljacket1983123]

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

[@swunt10]

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.

[@JRPeyesatsne]

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.

[@HondoTrailside]

This makes sense to me after 40 years building advanced structures in wood, though certainly not skyscrapers. One quibble is over the natural aspect of all this. The wood structures shown when he was describing human response were real sticks of lumber, or possibly glue lam beams that most people think are "natural". But these products are from the trees he promises not to cut. The stuff he is proposing is going to be as natural as a sheet of osb. I think we are talking Franken products here that may not be huggable but could be quite useful. We are also probably getting some Franken forests with heavy GMO engineered wood.

[@HobbyBots]

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.

[@mon2liu]

I would love to see these buildings in Vancouver. They sure beat the depressing concrete and glass buildings here.

[@BUILDINGWITHLOGS]

bang on!

[@biohazardx]

The Hybrid Super Tree can grow up to 35 feet in one year, and can be harvested after 1-2yrs, for pulp, woodchip or landscaping logs (it re-grows from the stump at a faster rate again, providing multiple harvests and marketable yields for years to come).

[@BenCrews]

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.

[@Preator497]

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.

[@socccerPlayerz]

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.

[@lmk10000]

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.

[@LanttuLoL]

1:16 I've seen how people touch, the wood... lost it xD

[@JRPeyesatsne]

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?

[@melnais11]

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.

[@cresentum]

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.

[@melnais11]

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.

[@vin3646]

my question is damage. If there is a huge or small damage how is that repaired?

[@pkzrdabest]

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.

[@misterchill]

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.

[@nonchalantd]

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.

[@user-nd8kz3pu1k]

이거 혹시 번역되어있는거 있나요..?

[@3ik3ik]

I believe the structure can be strong enough at the very least a mix of the other two+wood with big% going to wood can be tough as nails. Furthermore the relatively short longevity is beneficial the need to rebuild would drive a continues cycle of carbon trapping plus a never ending flow of work for the builders. Not to mention the fact that by side effect no one would end up living to long in out of date houses that waste energy compared to progression of varies technological advances.

[@renatochamlian815]

e a manutençao ?

[@HandsomeAlex25]

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.

[@akly88]

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.

[@MassDynamic]

saw a vid about hemp being much better at storing carbon than wood. also grows much faster.

[@Lintary]

He is on to something here as wood can be grown rapidly and sustainable I mean IKEA has been doing it for years and years now, cut 1 spot down, replant and move to the next, 10 years later arrive at the same spot to cut it down again. Also with the oils we have these days maintaining wood is extremely easy, just spraying on some oil once every 5 years will do the trick.

[@xxhellspawnedxx]

As he stated, the wood used is young wood. If I were to dare a guess at specifics, I'd guess he was using what is commonly termed "energy wood" because of it's extraordinarily rapid growth rate. In only 4-5 years, these trees can grow to be 15 feet tall, so plant these in abundance and presto, you'll have the old woods left in peace.

[@thexstupidxlamb]

Coming from the standpoint of someone who's studied environmental science, this is true. Since all life forms are carbon-based, any decay results in the release of CO2. The "fertilization" aspect comes with the nitrogen in the tree is also released back into the ecosystem to be cycled again. Forests and tree wood are huge "carbon sinks", and when building with wood, preservation techniques keep them from rotting and keep the CO2 from escaping into the atmosphere.

[@DeoMachina]

I was skeptical, but if an architect tells me wood is good enough, who am I to argue? I wish him the best of luck. Nice work using creative commons too.

[@vlakieste]

I did some quick, rough calcs and the amount of carbon in 1 m^3 of wood is between 0.2 tonne for a soft wood and 0.6 tonne for a dense hardwood. So, if he's rounding up, he's sort of correct, but it's a stretch...

[@zapfanzapfan]

1 tonne of CO2, not carbon. Lose an oxygen and add a hydrogen and you have the average formula for long chained carbohydrates. 1 tonne of CO2 ->0.65-ish tonnes of wood.

[@whocares2087.1]

how do you keep the wood from rotting?

[@orishejuukuedojor2736]

lam

[@meeeee9407]

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.

[@Germanbiscuts]

I was just simplifying it. You actually need a bunch of other materials that one must rip out of the Earth to get. Plus, you'll need an enormous blast furnace, and other things with it, all in one giant facility. Also, slag forms and you'll need to get rid of it. Finally, you must shape it in various ways that also require a great deal of energy. Then, there is the matter of transport (though, I do admit that all materials need to be transported, so I shouldn't include it.)

[@candl286]

What about longevity, how would we make them last?