Sustainable Building Effort Reaches New Heights With Wooden Skyscrapers (knowablemagazine.org) 98
The University of Toronto is constructing a 14-story building using mass timber, one of the largest and most recent projects to employ this innovative building technology. "Mass timber is an appealing alternative to energy-intensive concrete and steel, which together account for almost 15 percent of global carbon dioxide emissions," reports Knowable Magazine. "Though experts are still debating mass timber's role in fighting climate change, many are betting it's better for the environment than current approaches to construction. It relies on wood, after all, a renewable resource." From the report: Today, the tallest mass timber building is the 25-story Ascent skyscraper in Milwaukee, completed in 2022. As of that year, there were 84 mass timber buildings eight stories or higher either built or under construction worldwide, with another 55 proposed. Seventy percent of the existing and future buildings were in Europe, about 20 percent in North America and the rest in Australia and Asia, according to a report (PDF) from the Council on Tall Buildings and Urban Habitat. When you include smaller buildings, at least 1,700 mass timber buildings had been constructed in the United States alone as of 2023. [...]
In principle, mass timber is like plywood but on a much larger scale: The smaller pieces are layered and glued together under pressure in large specialized presses. Today, beams up to 50 meters long, usually made of what's called glue-laminated timber, or glulam, can replace steel elements. Panels up to 50 centimeters thick, typically cross-laminated timber, or CLT, replace concrete for walls and floors. These wood composites can be surprisingly strong -- stronger than steel by weight. But a mass timber element must be bulkier to achieve that same strength. As a building gets higher, the wooden supports must get thicker; at some point, they simply take up too much space. So for taller mass timber buildings, including the Ascent skyscraper, architects often turn to a combination of wood, steel and concrete.
In principle, mass timber is like plywood but on a much larger scale: The smaller pieces are layered and glued together under pressure in large specialized presses. Today, beams up to 50 meters long, usually made of what's called glue-laminated timber, or glulam, can replace steel elements. Panels up to 50 centimeters thick, typically cross-laminated timber, or CLT, replace concrete for walls and floors. These wood composites can be surprisingly strong -- stronger than steel by weight. But a mass timber element must be bulkier to achieve that same strength. As a building gets higher, the wooden supports must get thicker; at some point, they simply take up too much space. So for taller mass timber buildings, including the Ascent skyscraper, architects often turn to a combination of wood, steel and concrete.
No thanks (Score:3, Informative)
I live in a three story wood frame building and the cheapness and lightness of this structure worries me daily. The whole building rattles when the outside door closes. My dishes clink together when people go up stairs. You can hear everything.
Sure, if you build an experimental structure with no cost accounting and take your time to build massively, it might work.
In the real world, as soon as you let the unsupervised "free market" build these things, you'll have every corner cut and end up with toothpick structures built from crooked 1x3 stored outside from Home Depot.
Also, concrete and steel last much longer.
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Sounds like you live in the ElCheapo version there.
Re: No thanks (Score:1)
In the People's Republic of Quebec, housing construction is unsupervised. As a buyer you look at the plans and you have to understand that no one gives a fuck what the plan says.
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At least you have plans :P
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That sucks. Maybe move someplace else?
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Re:No thanks (Score:5, Informative)
Are you talking about mass timber or just traditional wood construction? Mass timber commonly involves thick beams of cross-laminated timber (CLT) forming entire walls, not just a wooden frame "skeleton".
I live in a newly built CLT house. It's only one story (though tall), but it's in an intensely windy location, which gets hit by hurricane-force storms usually multiple times per year, and where one year I had a storm with cat-5 strength gusts lift up and toss around a steel shipping crate (full of steel beams, timber, cast iron stove, glass, etc etc) like it was a child's toy (it's now anchored in place with boulders). The house is like concrete. Doesn't budge a bit, or even creak, in the strongest winds. You could drive a truck into it and the truck would get wrecked, not the house. My main concerns in the wind are the windows (either blowout, shattering from impact, or - commonly - being sandblasted by debris). The walls are going nowhere.
Here's a picture [naturallywood.com] of such a building going up (not mine) (and another [rezult-timber.com], and another [katus.eu]). All the wood that you see is solid all the way through to the thickness you see. Zoom in on the edge of those panels and look at the number of laminations. Each layer is oriented 90 to the previous layer, making use of the highly orientation-dependent strength of wood to give it strength on all axes. It's immensely strong. Remember also that breaking strength rises with thickness squared, and resistance to bending proportional to thickness cubed (which is why I-beams are shaped as they are).
The pieces arrive precut on flatbeds, are hoisted into place by a crane, and are attached together by frequent zigzagging bolts; assembly can be done in as little as a few days. I did the finishing on my own house; the main challenge (apart from a few bolts that penetrated through and had to be cut off and then filled as best I could) was that while the panels fit together amazingly well for prefab, generally under a centimeter, and sometimes just a millimeter or so off... that still means a huge amount of planing and sanding work to hide the seams, and there's a seam every meter or so on every wall and the roof. And then after that there was a LOT of wood to seal ;) And a lot of gaps to fill (sometimes sizable ones at the sealing), and bolts to hide. But the effect is lovely. Because it's real wood, not like particle board or something. One thing I actually found kind of touching was, the wood was so fresh, that there were some spots where it exuded little droplets of resin - felt like a personal connection to the trees themselves, and I left the resin droplets as a reminder.
There is of course no drywall and the walls are not hollow, so it does change how you have to build. In my place, it means that the wiring and plumbing is in the foundation and outside the walls (but under the insulation and roof cladding). I'm not sure what the typical approach for multistory houses is. For certain things like sinks and showers they had to put a groove in the wall for the pipes (but this was then hidden by tiling or fixtures). On the upside, everywhere is "a stud"; you can anchor huge amounts of weight anywhere you want on the walls and ceilings.
The wood has such a high mass to surface area ratio, and such a thickness, that it's not very flammable. It's still wood, and can still burn, but isn't prone to very aggressive fire spread, with panels usually being rated for 30, 60, or 90 minute exposures, and (unlike steel) remains structurally stable at high temperatures (its damage is through ablation). The outside chars and then insulates the thick interior. With traditional wood framing, beams have
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** at the ceiling.
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I want to be clear, I don't think mass timber is some sort of universal replacement for steel. You're not going to be building 100 story CLT skyscrapers. But it's a pretty impressive new product (it was only introduced in the 1990s, which is a blink of an eye in the famously change-resistant construction industry), and its usage is spreading pretty quickly. For good reason, IMHO.
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I wonder about the freshness you mention. That sounds like the wood is going dry and shrink as it ages, which may leave you with a plethora of surface cracks.
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Yes, that is a natural part of the aging process. The wood starts off with a completely smooth look (the seams between individual boards are nearly invisible), but takes on a somewhat "boarded" look with time.
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Yes, that is a natural part of the aging process. The wood starts off with a completely smooth look (the seams between individual boards are nearly invisible), but takes on a somewhat "boarded" look with time.
That appearance could be very attractive, if you're expecting it. And, I imagine that there's nothing preventing the home owner who wants drywall-like flatness to add a 1/4-inch sheet to achieve a traditional look.
What is known about potential heath risks for the resins used to laminate the boards? There's a lot of material, so even a small rate of outgassing might end up being significant. For that matter, is there a fresh wood smell, and does that dissipate?
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Either way surface checks can be fixed once, but as those big panels expand and shrink there will be constantly opening and closing gaps at the seams and between each solid piece of wood. The reason plywood doesn't do this is because it is relatively thin veneers, but full size lumber glued like plywood won't be so lucky. Keep that HVAC humidity steady in that building
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A normal stick frame building wouldn't stand up in my climate, so why even bring it up? It's CLT or concrete, take your pick. You can't just neglect the loads that the structure will experience.
The laminations opening up is a natural part of aging. It just gives it a slightly "boarded" look. It does not allow airflow through the panels.
CLT houses are insulated on the outside. It has no impact on the insulation. From inside to outside, it's: panels, barrier, plumbing/wiring, insulation, barrier, claddin
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(And as for the resin, I found like four tiny drops, each the size of an insect egg. We're not talking about it raining sap here)
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If the drywall doesn't go up fast enough, then some of the boards will have to be bent back into place [youtube.com], which actually happens in most such houses.
If the wood is too dry, it splits when the nails go in. Screws can be used in dry wood, but are more expensive and slower.
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My parents bought an new but unfinished house and spent the next 15 years putting drywall up. I do not recommend.
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Thanks for the pictures, that's interesting. Sheathing used to be structural on some old houses in the US, stick-builds are a semi-modern cost phenomena. It kind of amuses me that the state of the art in some areas is going back to basically synthetic log construction. Whats old is new again.
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There is of course no drywall and the walls are not hollow, so it does change how you have to build.
Just curious about the drywall. Sometimes drywall is nice to have in terms of paint, textures, drilling holes and then completely replacing the drywall, etc. So, wouldn't it be possible to simply put a traditional wooden frame on the inside of rooms to allow drywall to be put up? Wires and pipes going from room to room still need to be placed beneath the floor, but within the rooms, traditional wires, outlets, and plumbing could be used. Is that possible?
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To me, getting rid of the drywall is one of the best aspects of it. Why would you want drywall? Why would you want paint instead of stained wood? Why would you want flimsy drywall anchors instead of vastly stronger wood anchors? I don't get it. Drywall is awful. And as for replacement, you just sand down CLT, restain (blending with the existing stain around the sand point), and it's like new. Why would you want to have to rip out and replace a ton of drywall in the process? Drywall is also a black m
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"Mass timber or just traditional wood construction" are not the only two options. Glulam [wikipedia.org] and related engineered wood beams are the major part of this turn in skyscraper construction. This is definitely not "traditional wood construction" but does use normal beam construction (as in steel or pre-stressed reinforced concrete beam construction methods).
Mass timber construction is just a variation on Glulam beams, with a different form of beam, made practical by the low density of wood.
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I live in a three story wood frame building and the cheapness and lightness of this structure worries me daily. The whole building rattles when the outside door closes. My dishes clink together when people go up stairs. You can hear everything.
That's called "living in the projects".
Re: No thanks (Score:2)
Re: No thanks (Score:4, Interesting)
The massive laminated beams being discussed here are less vulnerable to the effects of fire than structural steel, which loses strength in a hot fire starting at only 300 C. Steel beams need protection from heat in a skyscraper -- the beams are commonly encased in lightweight concrete or other insulation for fire protection. A key reason that the Twin Towers collapsed was that the aircraft impact tore the insulation from the steel framework.
The outside of these engineered beams build up a thick layer of char that protects the interior of the beam, self-insulating. They don't burn up.
The risk of fire in any building is not the frame of the building, but the interior furnishings. By the time any fire attacks the frame of a building the interior is already gutted and the inhabitants have either escaped or been killed.
A little knowledge can be a dangerous thing, as the saying goes.
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The Roman apartment building was called an insula. [wikipedia.org] The better ones have survived to this day. The ones that burned down or fell down were notorious death traps.
Building codes and inspectors aren't great, but laissez-faire construction has its downsides.
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You should realize that the IBC (International Building Code) that everyone in North America adheres to since 1974. That does not mean every jurisdiction treats it as law, but if every builder follows IBC, then they are safe from being sued or having to redo expensive work.
That said, sometimes this get's applied incorrectly. For example California building code is only applicable to San Francisco and San Diego areas, because they are super dry climates, the only other place that might adapt the same buildin
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You can hear everything.
Your building was built incorrectly with poor isolation and no consideration to resonance. That's not a problem with wood, that's a problem with your building. I also live in a multi story wood building and everything is dead silent.
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No, that is a problem expressly caused by using wood, because the developers want to build cheap tiny unlivable "investment property". For every corner you take by choosing wood, you need counter measures for fire, sound, moisture ingress, that you would not need for concrete.
I've lived in multiple buildings to date:
- Wood frame 2 story house
- Wood frame 1 story house
- Wood frame 2 story apartment building
- 25 story Concrete Condo tower facing a park
- Wood frame 3 story townhouse building
- Wood frame 2 stor
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I live in a three story wood frame building and the cheapness and lightness of this structure worries me daily. The whole building rattles when the outside door closes. My dishes clink together when people go up stairs. You can hear everything. Sure, if you build an experimental structure with no cost accounting and take your time to build massively, it might work. In the real world, as soon as you let the unsupervised "free market" build these things, you'll have every corner cut and end up with toothpick structures built from crooked 1x3 stored outside from Home Depot. Also, concrete and steel last much longer.
So much this.
Many of the newer multi-story apartment buildings in my area are full wood construction. Watching them go up, they are really concerning. rather large buildings with a lot of mass, all resting on some 2 by 4's.
And we've experienced that this wood - it does burn well. And if the fire starts at a first floor apartment, it will consume the building all that quicker.
Granted, wood is a nice structural material. But a wooden skyscraper? My single story residence is wood framed. That works v
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And we've experienced that this wood - it does burn well. And if the fire starts at a first floor apartment, it will consume the building all that quicker.
Before they get the sheetrock in, those things burn like torches.
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And we've experienced that this wood - it does burn well. And if the fire starts at a first floor apartment, it will consume the building all that quicker.
Before they get the sheetrock in, those things burn like torches.
Yup, pine is an amazing wood, very easy to work with. But flammable AF.
And one of the components of the glulam glue is formaldehyde. https://rosboro.com/wp-content... [rosboro.com] I remember when there was a big to-do about getting formaldehyde out of things. I worked with it in some photographic darkroom chemistry. They seemed to be in a hurry to get it out of the processes.
And this is considered safe? https://csengineermag.com/glul... [csengineermag.com] Great - perhaps they should burn the glulam beams before installing them. 8
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As much as I want to care/like timber construction...
1. It does not belong anywhere that gets forest fires.
2. It does not belong anywhere with high winds
3. It does not belong anywhere that get's >M4.0 Earthquakes
4. It does not belong anywhere that get's humid
5. It does not belong anywhere that get's snow or >5mm of precipitation/mo
If any of those are true, the exterior walls and foundation must be concrete, and the roof must be angled to prevent precipitation from pooling. If you've lived in areas whe
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So you really don't anything at all about laminated beam technology. None of these five "reasons" are valid.
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There have likely been millions and millions of sturdy three-story (and taller) structures built throughout history out of wood and other traditional building materials. 14 stories is quite a different matter, but a three story building should not be a problem. You're dealing with a uniquely shoddy structure.
but one woodpecker (Score:5, Funny)
Re:but one woodpecker (Score:4, Informative)
The Japanese have been building large wodden structures for centuries, in an area prone to large earthquakes. They are actually more durable as the ability to move helps them survive the shaking. A lot of of them don't even use nails.
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This is a much more important reason than CO2 emissions.
For CO2 reductions I believe there is already chemical process fixes for both concrete and steel.
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Fire (Score:1)
Wood has a teensy problem as a building material - it burns. Sure, you can inject it full of fire retardent but given long enough t'll still catch light. If its a 2 or 3 story building not a problem, you'll be able to get out in time. In a skyscraper? I'd rather not take my chances thanks.
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See the above [slashdot.org] about CLT (last paragraph).
Re:Fire (Score:5, Informative)
Steel and concrete lose strength in fire, too. The Twin Towers didn't come down on 9/11 because airplanes smacked into them; they fell because the ensuing fires weakening the steel. The Grenfell tower in London - made of concrete - was a veritable death trap when it burned in 2017 [wikipedia.org]. Some materials handle fire better than others; but that's no guarantee - proper design counts for a lot more.
If you had bothered to actually read the article, you would have seen your concern addressed over several paragraphs:
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It wasn't the concrete that was burning in the Grenfell disaster, or the more recent similar disaster in Valencia, Spain. As you say, proper design is what counts, and that has to take into account not only what material is bearing the load but what other materials are used for thermal insulation, acoustic insulation, decoration, etc. and how the geometry channels airflow. Fast-burning plastic which creates poisonous gas can kill the residents long before a thick piece of wood burns through.
Check your facts (Score:2)
Grenfell only burnt because of the highly flammable insulation mounted on the outside a few years before.
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If you had bothered to actually read the article, you would have seen your concern addressed over several paragraphs:
When those multi-story apartments occasionally burn in my area - perhaps that weren't made out of wood after all, but the bastard contractors made them out of metal? 8^/
One of the side concerns is that if you have say, a 4 or 5 story wooden apartment building, the exterior walls are likely to be vinyl siding. So when something gets all excited and starts burning, the siding melts and burns. Then it spreads the fire rather nicely. But of course, a wooden skyscraper won't be having a vinyl siding - I just
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I do love when armchair engineers come in to drop an incredibly obvious point that they somehow think is a unique insight rather than something well known to experts in the field.
Wood burns, eh? I been no one ever though of that before! That's is for wooden buildings. Nothing else more to be said, Viol8 has spoken.
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Great sarcasm. Got anything useful to add or is that all you can manage?
Re:Fire (Score:4, Insightful)
When you add anything to the discussion beyond pointing out the astoundingly obvious that's already in TFA, I will have something to respond to. Otherwise, your post warrants little more than sarcasm.
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So thats a no then. Thanks for clearing that up.
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It's basically impossible to give a sensible reply to a sufficiently stupid post. So given your post I shall indeed admit defeat in being able to give a sensible reply.
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Wood has a teensy problem as a building material - it burns. Sure, you can inject it full of fire retardent but given long enough t'll still catch light. If its a 2 or 3 story building not a problem, you'll be able to get out in time. In a skyscraper? I'd rather not take my chances thanks.
It rots as well.
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This a teensy imaginary problem. And it also means that you do not understand the fundamental of fire hazards in buildings (unfortunately most people don't). Fires start with the interior furnishings of a building and the framework of properly constructed buildings are protected from that fire. It is only in the late stages of an uncontrolled fire, when the building interior is gutted that the fire has an opportunity to attack the structure. Long before that happens you have either already escaped the struc
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If (for the sake of argument) it were valid to lump it in with timber, however, then the fire threat absolutely couldn't be ignored,
Nice gimmick, but very ambiguous. (Score:2)
Re:Nice gimmick, but very ambiguous. (Score:5, Informative)
The Stave Church at Urnes is still on its original structural beams from the 12th century, and even contains some wooden elements fro the earlier church that stood before it. Ground beams, sills, corner posts, wall planks, aisle wall plates, roof, and various other elements are all original. The exterior cladding has certainly had to be maintained, but thick wood, properly protected, can last ages.
This is unlike most modern concrete, which contains a veritable time bomb. CO2 steadily soaks into the concrete and reacts with the high-pH environment to form calcite, lowering the pH; once the process gets all the way down to the rebar, and the pH drops at the rebar, it's no longer passivated, and very quickly begins to rust - not only robbing the concrete of its tensile strength, but expanding to ~6 times its original size, causing the concrete to spall out. Most concrete has a hard lifespan of 50-100 years. Thicker concrete resists this (the time to get down to the rebar is relative to the thickness squared), but the thicker the concrete, the more internal stresses act on it as it hardens. Solutions to this (as used in dams) get very complex and are not practical for normal buildings. Epoxy-coated rebar was hoped to solve this but does not appear to work in general. Stainless rebar works but costs like 5x as much. GFRP and BFRP rebar are relatively cheap, but have significant limits on how they can be used due to very different mechanical properties from steel, and still suffer degradation (though mostly fast initially and then slowing with time, vs. slow-then-fast with steel). CFRP (epoxy-coated), broadly similar to GFRP and BFRP rebar, has comparably little degradation and is even stronger, but makes even stainless rebar look cheap. Another option for steel is cathodic protection; active is generally considered more viable than passive, but even still that's an extra cost to set up the ribbon electrodes before the concrete pour (and ensure no shorts), and then requires continuous (though low) DC current after that. Lastly, can always go the Roman approach of "no rebar", but I'd recommend you look at the wall thicknesses on e.g. the Pantheon before you decide on that option ;) (also, when non-reinforced concrete fails, it fails all at once)
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I don't have the specialty knowledge to speak on any of those numbers. One thing though: It was my understanding that CO2 leaks from concrete, not in
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Your understanding is incorrect. You are probably confusing that with the production process of cement, which is very CO2 intensive (using heat to driving off CO2 from a mixture of what's mainly limestone, aka calcium carbonate, to produce calcium oxide**). Over long periods of time, the concrete basically undoes much of what was done to it in its production - recreating, to a degree, limestone. But in the process, it lead
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Curing concrete absorbs CO2 (Score:2)
This came up with the "earth ship" experiments where they tried to run a giant sized closed system terrarium with a crew inside. At least the first attempt they ended up having to do air exchanges due to missing factors in life cycle stuff and one of the factors was the concrete absorbing CO2.
Making Portland cement involves baking it and releasing lots of CO2. Then when you wet it and it cures, it reabsorbs 50-75% of the CO2 released in making it.
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That's normally a fairly safe assumption, but both concrete and steel are both egregiously carbon intensive because they use carbon for chemical purposes as well as for energy.
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As we all know, nobody tests construction materials and building designs for fire safety standards before approving them, right?
*eyeroll*
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As we all know, nobody tests construction materials and building designs for fire safety standards before approving them, right?
Not in the UK we don't.
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As we all know, nobody tests construction materials and building designs for fire safety standards before approving them, right?
*eyeroll*
OSB and engineered lumber. I remember on the news watching the Avalon Edgewater (in NJ) fire, that shit burns fast. Granted it wasn't helpful that they neglected to put fire breaks in that would have compartmentalized the fire somewhat, but we see it time and again, this stuff burns faster and hotter than conventional lumber. It puts adjoining and nearby structures at risk from the radiant heat, puts fire fighters at danger (the middle part of I beams burning away leaving only the flimsy top/bottom), and
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14 floors? Pffft! Amsterdam did 20+ (Score:2, Informative)
This energy-positive timber-hybrid tower will strengthen community in an under-construction Amsterdam neighbourhood [mvrdv.com]
In Amsterdam, a wooden residential tower by MVRDV and Space Encounters [domusweb.it]
The two firms join forces to design a tower of 22 stories featuring a wooden structure and a positive energy balance.
https://hautamsterdam.nl/en/ [hautamsterdam.nl]
I would so paint the last 3 floors red (Score:1)
Giant match!
14 Stories (Score:3)
Is 14 stories really a skyscraper?
Re: 14 Stories (Score:5, Funny)
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For very low levels of sky yes
Well played sir, well played indeed! 8^)
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The definition is arbitrary but Europe's first "skyscraper" was a 10 story building. The Home Insurance Building was widely considered the first skyscraper which was also 10 stories. But then the Equitable Life Building is considered by some to be the first skyscraper because it had elevators and it was only 9 stories.
Does the distance between the building and the sky change because someone built something different?
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Ignoring challenges of maintaining perfect external weatherproofing, human spaces also involve plumbing, and leaks happen from time to time. Water rapidly destroys most wooden structural integrity.
Oh hell yeah. Let me set up the scene.
Single story structure. My living room used to have barn board walls and real barn beams in the ceiling.
Whoever did the roof shingles, left a small hole in one of the valleys that was not sealed. About a centimeter. Every time it rained, some water got into it, and rotted out that bit of sheathing, then continued down the frame. Eventually it rotted a large section of the wall.
When I discovered it, the only thing holding the roof up on that side was the anci
Concrete is renewable, though (Score:2)
Its laid out ever so succinctly here :
https://youtu.be/tTJVbSEIqzE
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But not wood. (Score:1)
So for taller mass timber buildings, including the Ascent skyscraper, architects often turn to a combination of wood, steel and concrete.
That's not a wood building, it is a building containing wood.
Also glulam beams or panels are not just wood, they are glue! And it isn't Elmer's that you ate as a kid, it's just as bad as you would expect a modern glue to be for the environment.
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If we want to be more specific, we're talking about resins like melamine formaldehyde, phenol-resorcinol-formaldehyde and resorcinol-formaldehyde. The formaldehyde in all of them is a health hazard in uncured resin but not cured (except possibly in inhaled dust, but sawdust itself is carcinogenic, so...). They all have very strong bonds with the formaldehyde.
Melamine resin is heat-cured and low VOC; the other two cure at room temperature and have more VOCs.
Melamine is made from industrial urea, like a lot o
Sustainable? (Score:2)
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Concrete is very much recyclable and reusable.
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\o/ (Score:1)
"Timber Towers Spark Debate: Are We Fanning the Flames of Progress?"
"Wood You Believe It? New Skyscrapers Ignite Controversy"
"Smoke on the Horizon: Timber Towers Change City Skylines"
"Flammable and Fabulous: Wooden Skyscrapers Heat Up Urban Design"
"Smokin' Hot Architecture: Wooden High-Rises Spark Debate"
Glulam construction from the inside. (Score:2)
https://www.uidaho.edu/dfa/aux... [uidaho.edu]
There are a few nice pictures of the construction in that link.
If you insist on worrying worry about glue failure. Or that the glue is derived from oil.
North of Moses Lake WA along Highway 17 there is a line of glulam power poles. They are bigger than the usual residential power line, and smaller that the double-pole with cross-bar high voltage power lines. The larger single tree trunk poles are getting hard to find and power company is experimenting. They have steel tube po
there have been lessons learned why NOT to do this (Score:2)
There have been lessons learned why NOT to do this - key one is the points where the glulam are joined are notorious for catastrophic failure. The beams may be strong, and with enough glue and material, might be able to support as much weight as a steel beam... but when it comes to joining those beams, they can't support the forces, are very susceptible to moisture/temperature changes and FIRE. Don't need a materials science degree to know these simple facts.
They tried to be clever... They did this with br
No thanks (Score:2)
You couldn't pay me to live on top of 12 stories or more of firewood.
It's not wood anymore (Score:1)
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Cross-laminated timber emits 1/4th the CO2 [sciencedirect.com] as an equivalent concrete slab, cradle to gate.
No worries here (Score:2)
I'd love to work/live in what is essentially a giant bonfire. You could be the next "burning man".
Laminated wood production (Score:1)
Since it says they are using wood laminates, I have some concern because if production of that is anything like what a friend experience at a factory in Ukiah California, then production is very toxic to the local environment around the plant, from both liquid and gaseous pollutants.