So they're banning structures made of 100% biodegradable material that offsets carbon as it grows and is planted exclusively for this purpose, in favor of concrete and steel? Interesting.
"The movement" isn't exactly driven by Big Concrete to begin with though. It shouldn't be a surprise to anyone that there are a lot of people and businesses in the world that don't give a damn about climate change. If there weren't, we wouldn't be in this mess. "The movement" is trying to counter them.
The other thing is earthquake safety. Wood frame is often far more resilient to sheer stress than concrete/brick. Concrete can be reinforced to mitigate that, but I wonder how viable that is for buildings on the scale of SFH, not major developments.
Can confirm lived on tbe Big Island of Hawaii for three years. Almost all homes are made of wood with the houses literally standing on top of the volcanic rock or cement pilings. With frequent earthquakes (largest when I lived there was 6.8) the houses literally move, shake and flex.
It’s not just about reinforcement (like rebar or steel frames) but the concrete mix used. Even though it might not look it, most concrete used in buildings is flexible. The most earthquake proof building in SF is probably the Salesforce tower, which has a concrete core, not a low height timber framed house. Concrete has other great properties as well - it is waterproof, doesn’t rot, and is fireproof. On the emissions side, you can get flexibility and lower emissions by using newer air-crete mixes:
https://www.infrastructurist.com/what-is-flexible-concrete/
I still remember when the primary environmentalist movement was "save the trees"; doesn't more wood use imply more deforestation? The wood that's in buildings won't be capturing CO2, it's the live trees that do.
No, because all or nearly all building lumber in the US and Canada is sourced from sustainably-managed timber lots. In other words, trees are re-planted, and clear-cutting is no longer a common practice.
Wood results from captured carbon. Live trees are captured carbon, as is lumber. Dead trees decompose and release the stored carbon back into the atmosphere. Wood used for lumber, unless it’s some exotic wood from the Amazon, is usually sustainably harvested.
They don't seem to be weighing any factors at all, other than fire safety. Wood is renewable, cheap, cheaper to construct with, much more environmentally benign than concrete, very fire-safe (though not as safe as some), etc., etc.
As was mentioned by other commenters, affordable housing has a value that can be balanced against fire safety. Carbon contribution as well.
Everything has trade-offs. "Safe Enough" needs to be an allowable state.
It's a combination of both. NIMBYs love anything that makes construction more expensive because it limits construction, and also ensures that only the wealthiest can have housing, further driving up the price of their primary asset: land.
Do you mean land or real estate? Because if it's harder and more costly to build on land, that should decrease demand for it, and prices should fall. Demand for already-improved land should rise, though.
When there's a global limitation on what can be done with land, it limits how much use can be achieved by any given but of land. The demand is still there, but it's met by further and further out parcels of land, causing them to go up drastically in value. In addition, this causes all sorts of urban sprawl. Which is exactly what happened in LA. They had a huge downzoning of the entire metro area 50 years ago, driving up the prices of land everywhere, to the benefit of suburban NIMBYs in sprawl.
TL;DR, when the use of land is broadly limited, on the macro scale, the demand still exists and shifts the price of all land up on the supply-demand curve. The dynamics of limiting individual parcels a or small sections of land often have the opposite effect, though.
And at the same time, increasing the amount of a particular asset many in the US seems to love, at least based on the policies in many places: homeless people.
Increase for constructing single story housing, right? Do they normally construct denser housing with wood? Seems silly to mention NIMBYism when it pushes land use to more denser options, no?
It's pretty common these days to build "five over one" construction. This is typically a 3-6 floors of wood frame construction (Type 5 in some codes) over 1 or two floors of concrete (Type 1)[1]. It's a cheap way to build mid-rise buildings which would be banned by this proposal.
[1] Sometimes this is explained as the "five over one" meaning five floors of wood over one floor of concrete, rather than a reference to building codes. Either way the concept is the same.
>The one-plus-five style of buildings exploded in popularity in the 2010s, following a 2009 revision to the United States-based International Building Code, which allowed up to five stories of wood-framed construction.
This is published by an organization known for deceit. Thus, everything they write should be taken with a grain of salt with the full knowledge they engage in deceitful misinformation practices for the purpose of political action.
Yeah, empty about page is a red flag. And then this: “It’s a relief that Americans oppose Congress’s drug pricing proposals once voters learn the true consequences of these misguided reforms,” said Sally C. Pipes, the brief’s co-author and PRI president, CEO, and Thomas W. Smith Fellow in Health Care Policy.”
That this would make new housing more expensive, isn't generally viewed as necessary for fire safety, and is funded by the concrete industry, don't seem to be disputed?
Is there something that you actually believe is deceitful here? Is it the analysis of the impact of expanding the Fire District? Is it the data about the impact on building costs? Is it the claims about whether wood-framed buildings are safe enough?
Refusing to read and consider arguments from people you disagree with isn't a particularly useful strategy for gaining knowledge about a topic.
> Is it the claims about whether wood-framed buildings are safe enough?
This one, for me. I know nothing about it. Without further information, I wouldn’t want to conclude anything from a biased source (other than noting that the issue exists).
This isn't about disagreement. If somebody sincerely, honestly, and without conflict of interest has something to say on a topic, I'm interested. Especially if they have done some hard work around understanding and acknowledging other perspectives.
On the other hand, there are a lot of people out their paid to create and push propaganda. As a general rule, one shouldn't engage with it. If even the writer may not believe something, one isn't obliged to take it seriously. Indeed, I think it's a frequently exploited mistake to bring more credulity and good faith to something than the source itself does.
Much better to spend one's time finding reasonably sincere sources and reading those.
It's hard to find people interested enough to write publicly about something but having no vested interest in an issue. To that end, I still prefer to read things from people who I would disagree with rather than those I agree with, as it forces me to refine my beliefs and examine them more closely: can I actually find clearer evidence to reinforce what I thought I had believed that was in conflict with what I read? Can I refute it? Can I understand why they reached a different conclusion than me?
Sometimes I'll find that they were indeed making up an alternate reality or misrepresenting things. Sometimes I'll find something where the arguments being presented are unrelated to the data being presented. Sometimes I'll find disagreements in values leading to different interpretations of the same data. Sometimes I'll find that I learn something.
It does take discipline to do this, though: with many sources I have to be on high alert for anything that seems like it's trying to invoke my emotions to get me to agree with the article.
In the case of this article, I went and read their source material (the Los Angeles Department of Building and Safety report on this: https://clkrep.lacity.org/onlinedocs/2019/19-0603_rpt_dbs_%2... ), and found that the article fairly reasonably summarized the report. The last two paragraphs of the article are where most of their opinions are interjected, and I view their claims of the motivation of the backers with some skepticism. The claims about safety seem in line with what I could glean from the report, but I'm not very sure I understand the nuances of analyzing fire statistics across diverse neighborhoods.
Spend your time as you please, but you seem pretty cavalier about the risks and practical limitations.
The notion that you're personally always going to be able to see past propaganda is not giving enough credit to people who are good at propaganda. Everybody who falls for propaganda thinks they're smarter than that. Sure, they can spot the stuff that was meant to take other sorts of people in, but everybody has weaknesses.
But even assuming you could, you really can't do the research on everything. The world's too big. No matter what the topic, we all need filtering heuristics. And you give a really good one:
> Can I understand why they reached a different conclusion than me?
Often the answer is, "Because they were paid to." Or, "Because somebody was paid to amplify wacky outliers." For advertising, PR, and propaganda, all of the actual material can be taken with a grain of salt and the conclusions can be ignored, because the conclusions were foreordained.
As an example, take something you aren't personally well-disposed toward. Say, Q. How much time do you spend reading their ever-metastasizing set of theories and beliefs? How much have you personally refined your beliefs based what you read of theirs?
I'd hope the answer here is approximately zero, because a) it isn't worth your time, and b) there is a non-zero chance that it turns any given reader, yourself included, into a believer. That's the point of most propaganda, after all.
When an organization is known for deceit for political purposes, it means I must expend extra effort to determine what information they have twisted, what information they have intentionally left out, and what the angle is. It requires extra effort to attempt to discover where the deceit rests.
Why should I expend that much effort from an organization who's got an agenda and isn't known for their honesty? How much knowledge can be gained from looking through misinformation? Why should I poison myself with potential propaganda? What does it gain me then but an attempt to bait me?
I live in a small eu country... wood-framed housing is practically non-existant here. Not sure why, but we always joke about american houses, that are made out of "cardboard", where you hammer a nail to hang a picture, and break through the wall.
Yeah, you drill a hole, and put one of those plastic achoors inside, and screw a scew in, and hand a photo on the screw.
Our old-school socialist apartment buildings even have internal walls built out of reinforced concrete... drilling a whole to pull an ethernet cable through, means hoping for luck not to hit rebar
As someone who has lived in the US and Europe, I have made similar jokes. That said I've come to realize there's many advantages to the US way and in some respects the house I grew up in was massively overbuild:
Advantages of timber frame:
* Safer in earthquake
* Easier to do remodeling tasks like changing layouts, plumbing, wiring
* Easier to DIY
* Cheaper
Most of the apparent disadvantages can be offset:
* I've never seen it happen, but you are right drywall is easily damaged. It's also easily replaced though.
* Noise and thermal insulation can be added
* Flammability is mitigated with firestops, fire resistant drywall and codes that require multiple points of egress. Larger wood buildings have sprinklers.
That article contains this interesting nugget of information: "the proposal [...] is backed by an organization called Build with Strength. The campaign, led by the National Ready Mixed Concrete Association..."
So it seems this may have more to do with $$$ than actual safety.
this is exactly what regulatory capture looks like, deceptive and anti-progressive (expressly without the typical political association). as such, every ballot measure should be a default 'no' unless you thoroughly understand the second- and third-order implications of the measure, not just because it sounds good on the surface.
Another HN comment [1] notes this source is biased. Do we have an independent source confirming this move would not improve fire safety in Los Angeles?
Playing devil’s advocate, if I’m in a concrete business’s government relations office and I see a fire safety proposal that would help my company’s sales, I’m going to pitch in to help. That doesn’t necessarily mean the proposal was corruptly originated or advanced. (It does merit closer inspection.)
It doesn’t matter if it improves fire safety, since wood frame houses are already safe to live in. There is a point of diminishing returns that a change like this clearly goes beyond.
> doesn’t matter if it improves fire safety, since wood frame houses are already safe to live in
This is tautological. Whether they’re safe to live in is the entire debate. (Wood-frame house in a suburb has a different risk profile from one in a dense neighbourhood by brush.)
Safety standards evolve as the environment changes and our tolerance for risk, mediated by technology, decreases.
Debate #1: Are wood frame houses unsafe in Los Angeles, such that they should either be condemned and razed, or be subject to mandatory annual LA county safety inspections?
Debate #2: Are concrete houses so much safer than wood frame houses, that wood frame houses should be banned?
Right now, the concrete industry is backing a bill that endorses the view "#1 No, #2 Yes". Their detractors think that their view on #2 is biased, and that it is actually "#1 No, #2 No". I think that in reality it's "#1 Yes, #2 No", and that there's not enough political will to evaluate at all whether wood frame houses need more frequent fire inspections.
LA county is also in earthquake, flooding, tsunami, and wildfire territory, so any decisions that decrees one solution for all problems is automatically suspect simply for being incompetent versus the spectrum of safety scenarios available. For example, wood is more likely to survive earthquakes, while concrete is more likely to sustain damage; earthquakes happen constantly in this region, so much so that USGS has an entire California subsite dedicated to it.
Cynically, I expect the concrete industry is trying to say that concrete houses won't burn in wildfires, but by the time a change in building code reaches actual newly built homes in any given area, that area will already have had it's superfire and be relatively low wildfire risk for the next couple decades (since it'll be a long time before that much dry tinder can accumulate again).
The simplest way to counteract this bill would be to demand it require county inspection of all concrete homes after earthquakes, at which point the county would have to consider the real cost of structural collapse of concrete homes in salaried inspector terms, and reevaluate its stance on earthquake risk prevention versus fire risk prevention with respect to building materials. But I don't think anyone's thinking in those terms, which is unfortunate. If you live in LA, write your legislator a handwritten postal letter about it.
I think it would be more effective to require sprinkler systems indoors on wooden homes. I'm seeing prices of $1-$2 per sqft, which is absolutely reasonable (although I anticipate prices are higher in LA, square footage is typically lower).
It's also probably drastically cheaper for everyone than more frequent inspections.
> The simplest way to counteract this bill would be to demand it require county inspection of all concrete homes after earthquakes
They would likely need to be inspected after wildfires as well. Concrete won't burn, but I believe prolonged exposure to high heat can weaken or crack it. That might go doubly so for something like a single-family home. There's a lot less concrete to absorb the heat, and the upper layers have nowhere to vent the heat. I wonder if it would crack at the foundation as the roof expands, but the floor doesn't because it can vent heat into the ground.
Both of your points are relevant to #1, which considers only the safety concerns of wood frame homes.
Neither are relevant to #2, as neither focuses on the relative safety differences of concrete versus wood frame houses.
(Your second point suggests that sprinklers are necessary for all types of frames, whether wood or concrete or other, which removes the first point from consideration as a “wood frame only” cost, at least not without diving further into the comparison.)
Casually discussing #1 is easy, while casually discussing #2 is nearly impossible. For example: which is higher precedence in a relative comparison: fire or earthquake safety?
Assumption-by-framing that precedence is a frequent source of political manipulation by well-funded buyers, and it’s very effective. Identifying such a framing bias in the proposed legislation would be grounds to kill it in committee, if discovery of such a bias were politically unprofitable for the committee.
Safe compared to what? I realised when I moved to the US from the UK that the number of people I heard on a ~weekly basis who lost possessions or even lives in a house fire went from effectively zero to more than zero.
It just seems to be accepted as “ok” that houses are constructed from wood and can fairly trivially burn to the ground - especially given the standard of electrical wiring often found! I for one welcome any ban on wood housing construction and hope it spreads far and wide - and certainly will never spend money on a house that fundamentally represents the second of the Three Little Pigs.
(Edit: Perhaps LA also has earthquakes to consider - that’s fine and a trade-off worth discussing. Where I live earthquakes are non-existent, yet it’s still basically impossible to buy a house constructed properly)
>I realized when I moved to the US from the UK that the number of people I heard on a ~weekly basis who lost possessions or even lives in a house fire went from effectively zero to more than zero.
Where on earth did you move to where house fires are this common? I've never heard anyone talk about the possessions that they lost in a house fire because house fires are so uncommon.
Boston has a fire that displaces residents in a house at least once a week. Maybe every other week at most. And that’s just the city, not counting surrounding cities
I personally know several individuals who've had house (or trailer) fires. It seems entirely plausible that the comment was referring to personal interactions, not media mentions.
The USA also has a much more diverse set of climates than England - nit, your source is studying fires in England specifically, not the whole of the United Kingdom. I'm also curious where your figure for the USA Comparing rates of fires in hotter, more arid climates like Texas or California with England seems like a pretty big leap.
I'm also curious where your figure of 928 fires per day in the US comes from, maybe I overlooked it but I didn't see the USA statistics in your link. FEMA puts the figure at 1.3 million per year, or over 3,500 [1] per day. It's likely that there's a significant difference between the definition of a "fire" between the US and UK sources.
> from the UK that the number of people I heard on a ~weekly basis who lost possessions or even lives in a house fire went from effectively zero to more than zero.
I live in Mexico where houses are made out of concrete. A house fire is even worse, because you end up with a structurally unsound concrete shell that has to be demolished (and is quite expensive to do so). On a wooden home you simply rebuild on top of the ashes.
In 34 years in the US I have never met someone who has mentioned that they personally lost possessions in a house fire. Are you working in a field that causes you to interact with people who had their house burn down or something?
Maybe you live in new neighborhood. Last Summer a house a couple blocks from me burned, and while the fire dept. arrived quickly it was obvious that all the contents of the house were lost. Most of the neighborhood was built around 100 years ago so the structures have been through several generations of electrical wiring.
Also, when I was 13 my family's house had a fire and I lost all all of my possessions. I saw the remnants of my bedroom, but I don't think I ever got a real accounting of all that was destroyed. To this day I take photos of artwork and other objects and have (obviously) offsite data backups in case something happens. Its a very strange feeling to suddenly just have the clothing and objects on one's person.
There was a house fire on my street in Washington, DC, in late 2014. The owners sold it at auction to someone who had it taken down to studs and brick before renovating it. Some time in the ten years before that, an apartment building fire a mile south displaced multiple families, and left nothing but the facade.
> I for one welcome any ban on wood housing construction and hope it spreads far and wide - and certainly will never spend money on a house that fundamentally represents the second of the Three Little Pigs.
Fire safety is great, and if that's what you prioritize buying in your life, all the more power to you.
But focusing so heavily on one variable for something this complicated on a societal level seems like it would lead to a bad outcome because design and engineering always contains multiple competing tradeoffs.
Fire safety is certainly an important consideration when it comes to building, but is far from the only tradeoff to consider: what about building cost, environmental impact, building speed, repairability, and many other variables?
These numbers are pure fiction, but what if improving fire safety by 25 times increases building costs by 4 times, hurts the environmental impact by 5 times, makes the building twice as hard to repair when something breaks, and triples the construction time?
We do get house fires in the UK, as you know - that's what the bloody noisy red Denis lorries are for! To be fair, I don't know directly of anyone who has suffered from a blaze here either. I do have contact with several US citizens who have lost their homes to fire or "weather" (it can get quite breezy in Florida, for example)
Our sticks n bricks will generally get you a longer time to get out than timber only but that also depends on safe methods of egress and lots of other factors. Bear in mind that our floors are mostly wooden joists. On the ground floor (US first floor) we plank with chipboard and finish with carpet or laminate or tiles. The first floor (US second) has joists with wooden planking faced with carpet or laminate or some tiles, the lower surface is plasterboard. Our internal walls are mostly stud wall ie wooden too.
It's the plasterboard (drywalling) that slows fires inside a house. Dense gypsum is a really good way to slow fire down. It won't stop it though. Also you need to consider steelwork. My home has been extensively modified internally and we have a lot of "steels" - mainly to stop the first floor from falling into the lounge and kitchen and to hold the roof up. Ironically, we have a C section steel running along the long axis of the house with wooden props to the roofing purlins to assist with additional snow loading. This is in south Somerset! We have modern insulation in a 1920s house which means that snow doesn't instantly melt on the roof anymore. Some of the original roof insulation was hay - I pulled it out myself.
The UK is generally a lot safer weather, earthquake and wildfire etc wise. However we can't be complacent and neither should you. For fire it is quite easy to form a simple home evacuation plan. It will only take you a half hour. Get a fire blanket for the kitchen. Sort out your fire/smoke detectors and test them occasionally. Get at least one fire extinguisher per floor. You can get "water mist" extinguishers that will cover everything in the home apart from self igniting metal fires. I was recommended them by a Fire Brigade official. Get an escape ladder for upstairs if required. You can get single use ones for about £50 that take up a tiny amount of space in the bottom of a wardrobe and hook onto the window cill. Make sure your windows will permit egress!
It is easy to compare construction methods and see one as better but it isn't that simple. If you live in a place where your home is easily destroyed then cheaper and quicker reconstruction is indicated along with quick evacuation. I should also point out that quite a lot of people around here live in mud huts: wattle and daub (mud/clay with straw and horse piss, OK any piss will do) with thatched roofs and a lot of timber.
If your wood frame house has been on fire on the inside long enough to scorch a wood frame through the drywall or damage the drywall itself, concrete construction isn't gonna be much better for you the owner/resident.
If a California wildfire comes through and ravages the area, your fireproof building will still be there, but the walls will heat soak can and then set things on fire inside a fireproof building.
> If a California wildfire comes through and ravages the area, your fireproof building will still be there, but the walls will heat soak can and then set things on fire inside a fireproof building.
Walls would have to be made of iron to soak enough heat to burn anything inside. Typical walls are made of good isolators, you would need several days of constant fire to conduct that kind of heat. Windows on the other hand are typically what lets the fire inside. They just break after less than a minute of high temperature flame.
You also have to factor in the risk of earthquakes.
Los Angeles doesn't have frequent earthquakes, but because it's near a fault-line, that tail risk has to be addressed (the same way one wears a seatbelt, even though car accidents happen only a couple times in an individual's life).
I never knew that wood construction was considered safer than concrete construction when it comes to earthquakes.
Even the smallest of residential houses here (Serbia) are constructed with reinforced concrete as the base and reinforced concrete pillars, with brick walls filling in between the pillars and floors and ceilings: basically, a house is a reinforced concrete box that can move independently from the ground, and that's supposed to guarantee earthquake stability (it's definitely not done for fire reasons, since roof construction is still predominantly wooden). Construction standards have been heavily modified post-1963 Skopje earthquake (https://en.wikipedia.org/wiki/1963_Skopje_earthquake).
Buildings such as Ušce tower, built in this style, have not survived a big earthquake, but I imagine surviving a couple of tomahawk missiles is a good enough reassurance of stability: https://en.wikipedia.org/wiki/U%C5%A1%C4%87e_Towers#NATO_bom... (though I am fully aware that earthquakes and missiles are completely different when it comes to shocks a building experiences).
Interestingly, concrete based construction is one of the cheapest around here, possibly because most houses are built that way.
So I wonder, how prevalent is reinforced concrete use for houses in USA and esp California? Are there many houses and buildings built with insufficiently-reinforced concrete? I know that wood is a predominant construction choice, but what type of reinforced concrete are you comparing it to?
I'm starting to understand why some people go full "sovereign citizen". If I were American I would eventually go crazy from the sheer complexity of every aspect of life - complexity which is only there because there's a profit motive.
Where I'm from organizations which have both "National"(or adjective referring to the nation in question) and "Association" usually settle on being a corrupt clique - without any influence in matters other than their internal ones.
Doesn’t building using bricks exist in the US, or why isn’t it mentioned?
In my region in several places it was banned to build houses using wood hundreds of years ago and there a lot of beautiful stone houses still stand today. Avoiding wood in dense areas really makes sense I guess.
Earthquakes aside brick is really heavy and extremely brittle, so it is only cost effective if it can be sourced somewhat locally. The only real advantage to brick, aside from aesthetics, is that its a great insulator.
Additionally, brick is superior at weather resistance over time. 50 years from that brick will continue to insulate about the same as a new wall. You won't get that with wood even with lots of treatment over the years.
That site is talking about brick used as siding, not as something structural. And they're only getting an R value of 0.8 (which is minimal) because it is 4" thick.
4" brick gives you less insulation than even 1/4" of foam.
Brick houses in central and eastern Europe are usually build with clay block bricks like Porotherm with ? = 0,1 - 0,133 W/mK.
There are also some with 0,082 W/mK but usual combination is brick+insulation (i.e.: to have wall with U value less then 0,22 W/(m²·K) you can use brick with thickness of 38cm and 10cm insulation. For 20cm concrete wall you would have to use 30cm insulation.)
> The only real advantage to brick, aside from aesthetics, is that its a great insulator.
No it isn’t, the R value of wood is much higher. Imho the real advantage is longevity (doesn’t apply to earthquake areas tho) also when there isn’t wood available
A brick wall has less insulating value than a wood framed home with vinyl siding and drywall without any in-wall insulation. 4” of brick has an r value of 0.8, while drywall alone is at 0.5 before you add the 1-3.0 of the siding.
Nobody builds a house with 4 inches of brick though.
Have you ever been to a very hot country and wondered why they build with stone? Because it insulates.
Also half the comments in this thread are talking about how environmentally friendly wood houses are... and the other half are pointing out that a 'wood' house in the US is really vinyl.
But masonry doesn't work (there or anywhere) by insulating -- they use it for it's high thermal mass, which let's you effectively use the cool night air to keep the building cool during the day.
That's what insulation is - a material which changes its temperature more slowly than another material. You can do that by being a big thermal mass so that heat transfers but takes a long time to have an impact as a kind of thermal 'flywheel', or you can do that by making heat transfer in the material slow by having a high 'insulative value'.
Thermal mass and insulation are not the same concept. For example, if the environment is continuously hot or cold, thermal mass has no impact while insulation still does. This is most apparent during winter in a cold place, where the environment is always colder than you want the interior, and so thermal mass does not help. R and U values measure only insulation, not mass.
> My house is cool in the summer because it's still warming up from the winter.
That makes no sense. The amount of thermal mass you have in a home will help even out temperatures between day and night, but not between entire seasons.
A common 4-inch brick has an R-value of about 0.8, which is just slightly more than 1/2 inch plywood sheeting by itself. Depending on insulation choice, a wall built with 2x4 studs will have an R-value from 13 to 25.
Edit: I see someone else beat me to it. I'm a slow typer today...
Two layers of 4 inch brick with a cavity would be roughly comparable to a normal wood studded wall with drywall on the inside, empty cavity, then a layer of sheathing followed by a layer of siding. In other words, awful. I would hope that in the brick cavity there is some proper insulation.
Masonry structures are practically non-existent, especially in new construction. It's only used as decorative veneer or wall infill for self-supporting steel commercial buildings.
In Italy and Norway, maybe others, I don't know, wood constructions have been pushed quite a lot because they are more environment friendly than concrete and steel, can this be so different in los angeles?
A friend from Spain visited us in Christchurch New Zealand, and they couldn’t work out why all the housing was “temporary”: most of our homes are built of wood which appeared temporary to her. Solid structures also make sense in hot countries, where thermal mass helps keep your home cool without aircon. Another friend bought a large finca in Spain, that is stone (with rubble infill I think) and is hundreds of years old - very comfortable.
Here, wood makes more sense, because of cost and earthquakes. Many brick buildings and brick facades failed during the Christchurch earthquake. I own a home with a broken ring foundation, but completely lovable (edit: liveable) still, because it is a wooden home from the 30’s. The main issue with wooden homes are that they need a lot of expensive ongoing maintenance or they deteriorate. Not so much of an issue in the inner city where buildings get demolished, and replaced by new apartments or town houses.
They are 'temporary' in the sense they are not quite designed to last for centuries.
In Europe, you have 'Post and Beam' framing which means the underlying structure can last 'a very long time' while the non-weight-bearing walls can be replaced. And there's a lot of stone work which can last 'a very long time' as well.
But yes, stone is a problem for earthquakes.
I wish there was more research into modern materials for this kind of stuff.
I would hope that 'wood' would be something we use for decorative things we see, touch or feel, and that something more mundane can go into the framing.
Indeed, with such a 'post and beam' construction, a wooden house can last for 400 years (at least, where I live the oldest houses are around the age).
That said, in 1669, Amsterdam no longer allowed outside walls made of wood due to the fire spreading risk. Though that means that the construction would still be 'post and beam', but the outside walls would be make of bricks.
In Norway we have always built our homes with wood, but the last decade or so there have been a few buildings that would normally be built with concrete instead built with timber. Schools, hotels, apartment buildings and so on. Specifically they are using
This is just goofy. Timber-framed structures do well in earthquakes, and while they catch fire often enough during construction, once fire sprinklers are installed and people live there, serious residential apartment fires in modern construction are really rare. The most recent fire that comes to mind is Grenfell Tower, but it's larger than you'd normally use wood for.
In California that is defined as the “Wildland/Urban Interface”. That zone has been subject to much stricter building codes since 2008. Timber frame homes are allowed, as other factors (venting, roof material, rain gutters, roof material, siding material, landscaping) are dramatically more important.
The vast majority or LA county homes are not in a WUI zone, so wildfire extent can’t be used as an argument for this.
> Timber-framed structures do well in earthquakes, and while they catch fire often enough during construction, once fire sprinklers are installed and people live there, serious residential apartment fires in modern construction are really rare. The most recent fire that comes to mind is Grenfell Tower, but it's larger than you'd normally use wood for
Grenfell Tower was constructed using pre-cast concrete blocks, and was not timber framed [0]. The devastating fire [1] was due to flammable aluminium composite cladding.
Thanks, what a horrifying story. Amazingly bad materials and design - "Combustible panels with polyethylene were put up on top of insulation...made from polyisocyanurate, which burns when heated, giving off toxic cyanide fumes. ...the gap between the cladding and the insulation worked like a chimney to spread the fire."
Also funny if you consider we have "Fachwerkhäuser" (Timber framing houses) here in Germany which are up to about 800 years old. I would be curious if this will hold true for concrete houses in 500-800 years.
It's actually debatable if concrete in (most of) modern construction is on par with Roman concrete that lived to this day.
Sure there are compositions that are in fact better, but are they used in common buildings? I think the answer is 'no,' since costs won't cut themselves.
I am pretty sure you don’t want to depend on gravity to hold your home together in an earthquake. “scientists have revised ground accelerations at the two stations to 1.37g and 1.51g [vertical G force]”.
I agree. My point was that 'build it right' in the Roman definition was to use a lot of concrete, no reinforcement, and gravity to hold it all together. It is not really feasible given our expectations for modern buildings.
For earthquake reasons alone this is completely insane, and clearly a blatant attempt at regulatory capture by the concrete association. Just asinine.
For most of LA (apart perhaps from certain canyons and hill areas) the risk of fire is not significantly different from anywhere else. It's a cityscape. Earthquakes however are an omnipresent threat and wood frame buildings in general do far better. For example - many of the concrete buildings built along Wilshire blvd. in the westside may not survive a big quake.
In Germany, only a small portion of our houses are wood framed. But we have high standards, so our wood frames are protected and escape routes in special are covered by non burning plates. In addition, building stairs with the right wood can make them more sustainable to fire than concrete.
Overall, that's a very bad decision they made or want to make and there are even more technology available to prevent any form of fire in wood framed houses. Example: circuit breakers with lightning detection.
Not sure if you're aware, but America also has high fire standards for wood-framed construction, particularly for multi-family dwellings, which have required firewalls and sprinklers for many decades. Today, all U.S. model building codes now include sprinkler requirements for all one- and two-family homes, but this only became a requirement in the last decade, so many homes still do not have sprinklers. Electrical wiring is also subject to quite strict codes for the same reason.
does this apply to CLT as well? last I heard, CLT construction holds up favorably when it comes to fire resistance while having all the benefits of stick build construction.
-> Overall, it seems like wood construction does somewhat increase the potential risk of fire, mostly by allowing fires that do occur to be somewhat deadlier and more destructive. However, this effect is mostly swamped by other factors such as what state and city you live in, or whether you live in a house or an apartment. For a wood apartment in Salt Lake City, the risk of fire is vanishingly small; for a wood single family home in a tiny town in Arkansas, it’s much larger.
-> The most important factor for fire risk in a home is whether or not it’s sprinklered. Fire sprinklers reduce the risk of fire by an enormous amount, and sprinklered wood construction seems to perform about as well as sprinklered non-combustible construction. And sprinklers are cheap, costing about $1-2 per square foot (much less than it would cost to say, change a wood house to concrete).
-> For wildfires specifically, we see something similar - construction details such as fire protected eaves and class A roofs, along with things like community density, matter far more than whether your home is wood or steel.
Intresting that CA can be for the environment and for concrete (which emits a lot of CO2 during its production [1]) _at the same time_ somehow. Hypocrisy? Incompetence? Corruption? I'll let you decide.
good, now maybe we’ll get decent quality houses instead of garden sheds in CA. maybe something can be done too about all the shitty little craftsman shacks that are being flipped by entitled boomers looking to get a piece of your tech salaries.
There are a lot of relatively low-cost interventions that homeowners can do for hundreds-to-thousands of dollars (rather than the ~50% increase in construction cost of this proposal) that have proven benefits. Keep dry brush and plants more than 5 feet away from the home. Use fire-resistant roofs (which don't have to be expensive; asphalt shingles qualify). Prefer vinyl or stucco siding over wood. Cover attic vents with 1/16" mesh. Clean your gutters.
These are not complicated things, and many are things you should do anyway. They're much cheaper than building out of reinforced concrete, and more effective.
Yeah, no. It might not easily catch fire itself, but it definitely melt off and expose whatever is under it. They have cement composite siding that is probably a much better option if want something that looks and installs like vinyl.
As a structural engineer I almost can’t believe this news. Timber construction is great. Timber is a renewable resource and it has a high elastic modulus-to-density ratio. Steel needs to be transported and smelted down again in order to be re-used, assuming it doesn’t rust away over the years. Properly treated timber can last for hundreds of years.
What kind of treated timber lasts hundreds of years? When I think of treated timber I’m thinking of Bunnings treated pine... what is the industry standard timber for longevity?
Parent poster meant "properly cared for timber", not chemically-treated timber. Timber doesn't have an expiration date. As long as you keep it dry, it will last indefinitely. In fact, it becomes stronger over time. There are many 100+ years timber buildings in US.
For timber used outdoors, e.g. for making decks pressure-treated timber is used. It's a timber treated with pesticide (chromated copper arsenate). In the past creosote was used to treat things like wooden railroad ties and power poles, but it's no longer used because it's toxic.
If timber is properly seasoned with appropriate treatments depending on region it can actually last hundreds of years. We have redgum timber at home which was used some time in the late 1800s.
There is a lot of debate here with wood vs concrete with merit on both sides. I can see using concrete for the foundation but just me personally, I am going with a steel Quonset hut on a concrete foundation. They are cheap, durable, easy to install. These would probably be ugly in a city I suppose unless someone could find a creative way to make them look nice. I am waiting for steel to come back down in price. Two thirds of it will be a workshop/garage. One third will be insulated with either closed cell foam or aircrete, I haven't decided. It gets cold here. Quonset huts are also much less expensive to move around. I'm honestly surprised Los Angeles has not used Quonset huts for the affordable housing or even homeless shelters.
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