Once I had the idea for a project (never completed) to analyze the differences in pictures accompanying articles across Wikipedia's languages. The results were about what you might expect. For their respective articles on "Food", you'll find:
- English: a photograph of vegetables, meat, bread, beans, and milk
- Japanese: a room full of tuna at a large fish market, white rice, and water
- Russian: potatoes, onions, spices
- Italian: a 17th century painting of some food
- Esperanto: the cover of an Esperanto book about food
- German: bar charts tracking food prices (and no pictures of any actual food)
It's interesting how Wikipedia makes it easy to jump between languages, yet each language's maintains its own identity and conventions. I've heard people propose to just start copying photographs from English Wikipedia into others (which tend to have far fewer pictures), and editors for those languages asking people to please stop.
Wikipedia has a list of tallest wooden buildings, very few of which are actually complete: https://en.wikipedia.org/wiki/List_of_tallest_wooden_buildin...
I recently read about the one in Tokyo which is supposed to be 350 meters tall for a forestry company's 350-year (!) anniversary. The article claims it will be 90% wood, 10% steel: https://e360.yale.edu/digest/tokyo-plans-to-build-1-150-foot...
What? I hold this belief that isn't. I understood the point about keeping its structure well while burning, but it doesn't make it "fireproof"!
Wood obviously isn't fireproof. But we have regulations that say that in buildings "fireproof" just means it will last some amount of time before burning or degrading/collapsing.
Ex: if you're in an office with a wooden door in the US, go check the side of the door where the hinges are. Most will have a small metal plate indicating that they're rated for some amount of time for fires.
It will look like this: https://www.google.com/search?biw=1903&bih=898&tbm=isch&sa=1...:
Note that the trees are all still there. Wood is surprisingly difficult to burn, and if it does, it will do so very predictably, slowly, with relatively low temperatures, while maintaining structural integrity.
This video makes the difference very clear: https://www.youtube.com/watch?v=G-J86Ka9MkQ . It's not that wood can't burn, it's that it won't burn significantly.
I wager that if we built forest like structures out of steel and concrete they'd be far more fire resistant than natural, wooden, forests even if the amount of fuel at ground and canopy level was kept constant.
This whole wooden building thing is great for a variety of reasons. That doesn't mean it's not inferior to steel/concrete when it comes to resisting a major fire. Just because it's inferior doesn't mean it can't still be "good enough". Trying to claim that a wooden structure has superior fire resistance to a steel/concrete/masonry structure is an exercise in mental gymnastics.
CLT or Mass Timber buildings are very different, there's basically a crapload of wood and it is very dense, so dense it can't burn well because oxygen can't get to it very well.
It is essentially the difference between trying to burn kindling vs a single large log.
Depends on the type of wood. There are some trees like Aspen that are natural fire barriers because they don't burn well. Unfortunately they're not worth much, so in places like BC that have a big logging industry they spray them with Round Up after the major forest fires. It's one of the real reasons that fires here have become so massive lately.
Plasma, cutters, on the other hand, cut by melting.
Plasma cutting liquefies the metal with electrical current then blows away the molten metal with air.
Take an oxy/fuel torch to a piece of wood and you will quickly have a self sustaining reaction even once the extra oxygen supply (torch) is removed.
Never the less, very exciting to see wood so prevalent in new construction.
There was this recent discussion on new wood frame midrises being very prevalent.
glulam = glued laminated timber AKA pieces of regular timber stacked & glued together
CLT = cross-laminated timber AKA glulam but instead of stacking the lumber, you lay it out in perpendicular layers and glue it together
LVL = laminated veneer lumber is like the above, but made like plywood out of wood bits instead of solid lumber, with a hardwood veneer on the outside
The wood is also treated to be fire, moisture, and insect resistant
It sounds like gluing, treating etc. etc. would really impact the "greenness" of this building
However, I was thinking that for a highrise timber building, you might need way larger column cross sections than what we're used to seeing (24"x24" - 36"x36" or larger). The typical wood frame construction method of using a ton of load bearing sheathed stud walls scattered throughout doesn't work with these taller types of buildings. You start to see post and beam/panel type framing, which means higher compressive loads, which means larger member sizes.The spruce/pine/fir trees slated for harvesting softwood lumber here in Canada don't seem to reach that size. Hence, you probably need engineered wood products. As a bonus, you also get better and more consistent mechanical properties.
In any case, anything is better than concrete.
- My diagnostics table can support a load of 2000lbs. You could park a golf cart on it.
- my Stronghold work bench will handle up to 8000lbs of load. You could park an F250 on it.
both of these are maple top/butcher block.
I wonder what the limit is for wood?
"the masonry walls were braced with an interior frame of cast and wrought iron"
There's a building boom going on around my office. The steel and concrete office tower next door is by far "sprouting" the fast. On the other side is a residential tower where half of the building is a 20+ floor concrete tower, and the other half is a 5-floor wood frame structure.
The concrete tower is going up faster, despite this being the same construction project. Perhaps what I'm missing is that a CLT build is more similar to steel construction than a wood frame building. Perhaps a real civil engineer can weigh in...
In the last few seasons, in particular, a bunch of the houses use pre-built wall (and even floor) "cassettes", also called closed-panel frames, that come with everything from the factory -- not just structural framing, but layers of insulation, breather membrane, vapor barrier, etc., complete with inside-facing gypsum drywall -- and simply lock together.
There are also lots of examples of custom off-site-engineered steel or wood pieces that are CNC-machined (almost always shipped from Germany or Switzerland), and also very fast to install, partly because they can machine them to a high precision. At the construction site, it's just assembly.
Another fun fact - alot of that nice looking wood had to be covered up with drywall for fire code compliance.
Fun fact, UBC has like 3 18-19 story dorms with million dollar views of the entire surrounding area.
So the claim for taking less time than a _concrete_ building is plausible for this location (I assume it's pretty cold compared with other climates). However like you mentioned, a _steel framed_ building would be similar in build time, since the elements can be hoisted and joined in the same way as a CLT building.
But that also depends what your slabs are. Most steel framed buildings use concrete slabs, which need to be poured and set, but with high early strength concrete and propping, this takes less time than a conventionally formed concrete building.
Concrete buildings can go up really fast, I've seen 5-6 day cycles on jobs. It depends on the complexity of the structure and again the ambient temperature (among other things). So yes concrete can go up faster than CLT as you noted.
As an interesting side note, the article mentions that the top floors of this CLT building use concrete for mass to limit swaying.
Although if you don't like the "Scandinavian" school of design. You are probably not going to like it anyway.
Winters are always tough, but climate change seems to be exacerbating it. Where, once upon a time, it used to get cold and stay cold, now the temperature bounces back and forth across the freezing point, and, from what I can tell, it's taking a serious toll. The streets are increasingly a giant mess of potholes and spalling, the sidewalks are a mess, and even the buildings are starting to fall apart. Yesterday I heard about a person in my neighborhood being hit in the head by a falling chunk of masonry.
Any news on how it is going?
There aren't even many 18 stories tall buildings in Oslo.
I grew up in one that was about 100 years old and where the exterior was all timber covered with plank. Originally there was sawdust added as insulation, but that was replaced at some point in the 1980's due to the fire hazard.
Of course this building is all specially treated wood, and the structure is under a lot more strain, so it's not guaranteed that it translates well, but wood that's treated properly can last a long time.
Granted, it's only 6 stories, but I think we can forgive that, given that it's 500 years old.
People also ask about fire resistance, but the outermost layer gets charred which then protects the inner for quite some time, compared to traditional steel beams where the heat makes the steel soft. So even though the steel doesn't burn, it needs special fire protection to stay stable for long enough for people to evacuate.
What? Tensile strength of steel is like 400-1200MPa, Bamboo is < 100 MPa.
"Although, the tensile strength of steel is 2.5-3.0 times higher than bamboo and the specific gravity 6-8 times that of bamboo; but by counting their tensile strength/unit weight (bamboo vs steel), the tensile strength of bamboo is 3-4 times that of steel."
As we were looking at a return capsule I noticed that the interior surfaces were finished with some kind of wood, which struck me as odd, and I asked if it was for aesthetics.
The astronaut standing near me explained that wood had the best trade-off of many criteria including weight and durability, and the goal was not to look like an 80s station wagon dashboard.
The current recommendation is 2x6 exterior framing with 24 inch spacing. This results in a durable and energy efficient home.
I know metal roof tiedowns ("hurricane clips") were created to solve the issue of roofs being peeled off wholesale by high winds catching them under the eaves and lifting.
Building codes in hurricane prone areas basically require you use all manner of various stamped steel plates and hangers to hold things together to compensate for the fact that nails tend to rip out of things if you pull in the right direction.
Here's a clickbaity-but-useful-article showing some different designs, and the Welsh Preseli community is particularly interesting for there sharing of designs. A quick google will find you lots of resources for all budgets.
Your local lumber yard. Wood is cheap. The easiest way to make a robust structure out of wood is to just use more material than you normally would.
If there's no such thing as objective beauty measures, then please explain to me why European cities with predominantly traditional architecture have vastly higher numbers of tourists than European cities with predominantly modern architecture. You can't argue it's due to lack of history, or culture, or any other measure, as Europe is vast and diverse, and you can control for all of those other variables.
There's weirdos who actually enjoy Brutalist architecture. But the vast majority of us clearly do not. That by itself should give you a hint that there is such a thing as "more beautiful" and "less beautiful".
I also find a few brutalist buildings attractive. My soft spot for brutalism probably comes because as a kid I played on a brutalist playground, so it kind of just feels like the “natural order” of things to me, whereas someone who grew up around a different set of architecture might feel more at home in their “natural habitat.”
Just not the majority of us. If it were otherwise, Moldova would be overflowing with tourists. As it stands, it's by far the least visited country on the planet. Sure, there are other reasons for that as well (political, cultural, economic), but to fight me on this point is ludicrous, in my opinion.
Do the vast majority of people go to Moscow to visit the Kremlin, or do they go to visit a random Brutalist neighbourhood. You and I both know that most tourists just don't do that. Why? Because they find it unattractive.
Therefore, people do make value judgements about beauty, and when a vast number of them say something is beautiful, and something else is ugly, I'd say there's objective data to be extracted from that.
Edit: Outside of how ridiculous this statement is, how does one bring a charred wooden high-rise back up to code?!
I think it was in relation to the San Francisco fire department.
Aluminum is one of the butter metals.
Trusses on the other hand are quite dangerous in a fire.
Truss roofs are made from steel of various shapes, even I-beams, and wood. I'm only asking for clarification if all truss designs regardless of material are problematic in a fire.
It's also easier to repair, as you can just replace the damaged wood. With concrete that's not so easy, and in some cases it can be hard to even gauge how damaged concrete is from fire damage.
The standard of workmanship (particularly in the installation of plasterboard or sheetrock) is a critical component to the necessary fire resistance
Many factors when thinking about which is better.
Dirty water and a bad choice of steel will lead to corrosion, so don't use those. Purify the water and/or use a different type of steel.
For a dramatic demonstration of how shallow a fire actually penetrates wood over a short period of time and how well it insulates, see here:
(Promotional, but informative nonetheless)
I would never choose to live or work in a multi-Tennant hi-rise due to fire risk.
From the internet:
Average building fires reach temperatures of 700 to 1000°C.
Steel weakens dramatically as its temperature climbs above 230°C, retaining only 10 percent of its strength at 750°C.
Wood generally does not ignite until it reaches 250°C. Once it catches fire, wood develops a protective insulating char layer.
After 30 minutes a large wooden beam will have lost around 25 percent of its strength in a 750°C fire and retain structural integrity – a steel beam will have lost 90 percent strength and will have failed.
But the comment above is referring to a specific treatment of wood by charring the outer layer to make it act as a fire retardant.
It's charred, but not charcoal. And yes, mostly it just makes the ignition temperature go up. But that's half the battle for fireproofing. You're mostly not trying to stop it from ever burning, but giving people enough time to evacuate, or the firefighters to put it out with water.
Also steel production procduces a lot of CO2. So much in fact that some steelworks are switching to hydrogen instead of coalbased for its steel.
TL;DR: carbon sink, pulp wood rather than old growth, trees get replanted.
I think that is all fine and dandy, but I personally would prefer an article simply describing the building. I don't think it's necessary to go the "this is green" or "better than concrete" route. For me good is good, that's it. Don't need to play towards a debate.
In other places, the greenest building is the one that is already standing. Even if it may be made from concrete.
Every place has it's own most adequate materials. In Norway it may be wood, in Japan it may be bamboo, but in many places it is concrete or some upgrade thereof.
I didn't like that the article is basically an advert.
I stopped reading at that sentence. They went too far.
I suppose we could get into the weeds of 'sustainability', in that case, unless you're proposing to stop all construction of any decent height, this is probably the best we can reasonably expect.