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99PI's coverage of forest fire policy and design was really provocative: https://99percentinvisible.org/episode/built-to-burn/ https://99percentinvisible.org/e

99PI's coverage of forest fire policy and design was really provocative: https://99percentinvisible.org/episode/built-to-burn/ https://99percentinvisible.org/episode/built-to-burn/ 1. Our entire approach to fighting forest fires may just be making them worse. 2. Smart and simple design decisions can save houses. A house can be thirty feet from an entire forest on fire and never burn down. We learned this through hardcore experiments in Canada where they built homes to test and lit forests on fire nearby. One of the immediate takeaways was to change roofing materials to resist embers, but there are other options for materials and landscaping that could make homes basically impervious. The problem is probabilities. Fires are common, constant. They are exceedingly rare in any one location though. So fire resistant design is no one's urgent problem, fires are always something that seems like it will happen to somebody else.

athenot 8y ago
That's the same problem in the South East with tornadoes. They happen nearly every week (in summer) and can destroy neighborhoods. Yet we build lightweight framed houses and rely on insurance because the overall odds are low.
- danielvf 8y ago
  I agree with your general point. Though we are talking many, many orders of magnitude less damage from tornadoes in the Southeast when compared with California forrest fires. My state gets an average of 20 per year, and almost all of these hit uninhabited areas. If a tornado destroys four houses, it makes state news.
  - js2 8y ago
    A better comparison is hurricane prone locations. After Hurricane Andrew in 1994, Florida conpletely revised its building codes to require homes to withstand a major hurricane. It’s possible to build a home on the beach to even withstand a catastrophic hurricane, but at possibly double the construction cost. https://www.nytimes.com/2018/10/14/us/hurricane-michael-florida-mexico-beach-house.amp.html https://www.nytimes.com/2018/10/14/us/hurricane-michael-flor... I recall after there were bad fires in the Everglades many years ago there had been some work to build a foam that could be sprayed on a home to protect it in advance of an approaching fire. I think the person who came up with the idea was inspired by the amount of liquid diapers can hold. I wonder what came of that. Edit: http://www.spokesman.com/stories/2006/jul/19/gel-inspired-by-diapers-may-be-firefighting-tool/ http://www.spokesman.com/stories/2006/jul/19/gel-inspired-by...
    - Klathmon 8y ago
      I know some people in South Carolina whose beach house (on stilts and everything) withstood Irma just fine, however it had to be demolished because the beach had eroded enough that it was basically over the ocean now, and it was infeasible for them to dump enough sand there to have it be over dry land again. It's absolutely possible to build solid safe housing from most natural disasters, but it costs money, and often a lot of it.
- cortesoft 8y ago
  I mean, are we sure that isn’t the right choice? Depending on the difference in cost and probabilities, it might make economic sense to act this way.
  - neilc 8y ago
    "Insurance policies for extreme weather-related losses -- especially for floods and for coastal wind damage associated with hurricanes -- are not priced to reflect the real risk ... as a result of government intervention in property insurance markets, through either rate regulation or direct government provision of subsidized insurance, private markets no longer generate price signals regarding the cost of living in severe-weather regions." https://repository.law.umich.edu/cgi/viewcontent.cgi?article=2751&context=articles https://repository.law.umich.edu/cgi/viewcontent.cgi?article...
- pixl97 8y ago
  Tornadoes are rather improbable at any one particular spot. Wildfire occurs at regular intervals.
  - rconti 8y ago
    Pretty much every wildfire I remember since I moved to CA has happened in a place that hasn't burned before. I'm not sure your theory holds up. In particular, because a truly burnt-out area is VERY unlikely to burn again any time soon.
    - pixl97 8y ago
      This is why we use data and not your memory.
iambateman 8y ago
That 99PI episode was one of their best. The image of a mudslide happening because of denuded mountains was terrifying. I’m reading antifragile right now and he’s talking about systems which improve with a certain amount of volatility and stress. It seems forests are “antifragile” on their own, and our efforts may in fact introduce fragility.
- curiousgal 8y ago
  >I’m reading antifragile right now I commend you for that, I just find his writing style to be so annoying that I can't even finish reading a simple article of his.
  - claytoneast 8y ago
    His books are less grating than his short pieces.
    - stouset 8y ago
      They really aren’t.
  - iambateman 8y ago
    Totally agree. I lived with a guy from the Middle East for several years, and it actually helps to imagine his voice when I read Taleb.
- gowld 8y ago
  Seems obvious that if you expose a system to stress, whatever survives will be stress-proof; while if you hide stress from a system, it's a disaster waiting to happen. Same story with allergy immunities and used cars.
  - darkerside 8y ago
    What's the used cars example?
dbetteridge 8y ago
See also http://www.as3959.com.au http://www.as3959.com.au And the australian BAL standard for bushfire rating houses
- roel_v 8y ago
  I'm working in an Australian research project (for the Bushfires Crown Research Center) in which we're modeling risk, from bushfires but also earthquakes and flooding, using (amongst others) upgrading BAL levels as an intervention option. It's incredible how little is known about bushfire modeling at scales that are relevant for policy making, our work is met with a a lot of interest at e.g. firefighter's conferences. The crux of the issue is though (from a policy perspective) that defending against low recurrance interval events is most cost effectively done by restrictive zoning, which is (politically) a very hard sell. Observed preference is that people actually prefer band aids over real solutions. It's a hard problem.
Amezarak 8y ago
The article doesn't mention it, but controlled burns are actually a regular occurrence in the east and southeast US. I always assumed it was some decision by the Californian state government to not do so. The rest of the country is not stuck in the mindset described in the article. Fires are necessary for ecological reasons. You can either start them on purpose and control them, or you can wait until they happen anyway and watch them get totally out of control. Exacerbating the situation, I heard on NPR this morning that some POAs in California forbid cutting down trees on your property. Something has to change. Even if you put a complete stop to human-caused fires somehow (not possible) and stop climate change tomorrow, you will still have fires from lightning strikes, etc. You can either thin forests and underbrush (incredibly labor intensive) or you can have controlled burns.
- sgc 8y ago
  I have not heard of extensive controlled burns in any western state. It is just too large and the forests here burn too hot and fast in terrain that is too rugged. Of course there are some controlled burns in California and other states, but the large scale burns required are not practical by any measure. California is considered to have one of the most advanced firefighting forces in the world. They inform the fire control decisions, and know the importance of controlled burns. Maybe it is just a tougher nut to crack rather than assumed incompetence?
  - Amezarak 8y ago
    > I have not heard of extensive controlled burns in any western state. It is just too large and the forests here burn too hot and fast ...Because of the lack of controlled burns combined with weather conditions. California is not larger than the eastern US. We do very large controlled burns here in rugged terrain. As far as I can see, it's a lack of political will and funding, combined with the reality that it's gone so long that its much more difficult than it should be. There are a few prescribed burns done in California, they're just not anywhere near the necessary scale. California can either bite the bullet now and dramatically increase the number and area of controlled burns, or watch as things get worse and worse. There is no alternative. I'll repeat again: fires are a natural part of the ecology, with or without human intervention. You can either do it yourself and lessen the impact, or wait for nature to do it and have regular disasters. EDIT: Just to get a sense of scale, the southeast burns eight million acres in prescribed burns annually. The west burns about three million. California looks to be only in the tens of thousands. The Camp fire has burned approximately 138,000 acres at the last report I can find. http://www.stateforesters.org/sites/default/files/publication-documents/2015%20Prescribed%20Fire%20Use%20Survey%20Report.pdf http://www.stateforesters.org/sites/default/files/publicatio...
Cthulhu_ 8y ago
> A house can be thirty feet from an entire forest on fire and never burn down. That test in Canada seems to have been done under pretty much zero wind conditions though; the California ones (as also mentioned in the article) deal with high winds as well.
- microcolonel 8y ago
  Add in some sort of tarp, maybe. If you don't have whole rows of houses on fire at the same time, you can actually fight those fires.
- fouc 8y ago
  The linked article mentions a 100 feet buffer zone, perhaps to take that into account.
  - deleted 8y ago
    [deleted]
  - asah 8y ago
    These does are affecting urban areas of California, not just wilderness. 100 feet of urban California real estate costs substantially more than the house - houses are often built right up to the property line, and lots are measured in sqft, not acres.
    - gnud 8y ago
      Presumably, if space is that expensive, there's not vegetation next to your house, but another house.
    - nostrademons 8y ago
      The article mentions that as a problem. Dense urban areas have a compensating advantage, though: it's much more economically efficient to set up a firebreak and prevent the fire from reaching 100,000 residents in a densely-packed neighborhood, than it is to set up a perimeter around the one wealthy person's home built in the middle of the forest. The article seems to be suggest (but doesn't explicitly state) a policy like this: "Use public resources to provide a fire protection around the urban growth boundary of major cities, but if you're a homeowner outside that boundary, you're on your own. Design your structure to survive a fire in the surrounding wilderness. We won't suppress fires within the wilderness anymore." In other words, instead of shooting for containment, where the firefighters attempt to control the size of the fire and eventually put it out, they just let the wilderness burn periodically and protect habitation. The added benefit of this is that once the brush is cleared out, future wildfires will be less strong, since there's less fuel. Also makes sense in economic free-market terms, where public resources are used only when they can defend many properties at much lower cost than the property owners defending them themselves, and property owners who are not situated to benefit from these efficiencies of scale are responsible for defending their own property.
gowld 8y ago
If an individual house can fireproof itself, than it should fall out of insurance rather easily -- if you want to save $1000/yr or something on home insurance, build to the insurance code, or declare that you are happy paying a higher insurance rate.
ortusdux 8y ago
Great episode. I talked to a friend that is an environmental scientist/forester about it. She is doing more and more fire risk surveys for homeowners. She said their portrayal of the situation was very accurate. Another relevant podcast episode is this one from planet money: https://www.npr.org/sections/money/2018/02/16/586600540/episode-825-who-started-the-wildfire https://www.npr.org/sections/money/2018/02/16/586600540/epis... They explore wildfire investigations and the legal fallout. It is a great explanation of why PG&E's stock lost 1/3 of its value.
onetimemanytime 8y ago
>>A house can be thirty feet from an entire forest on fire and never burn down. We learned this through hardcore experiments in Canada where they built homes to test and lit forests on fire nearby. Fires in CA apparently went as high as 300 feet (~100m) so no, that would not have helped. Heat alone, with zero wind would probably melt everything with xx meters. If they want to build, don't build in forests or clean out a zone and build a 50-100m buffer. If it was not burned today, it will be burned tomorrow.
- fouc 8y ago
  Height doesn't necessarily imply width. The linked article does mention a 100 feet buffer zone.
  - onetimemanytime 8y ago
    width or not means that there's a LOT of material to be burned and to collapse into the next lot. I've burned wheat fields after 90% of straw was removed and I can tell you that in certain days it rises to 10 feet and you cannot stay close to it, it's unbearable. Not necessarily flames but heat, that barely visible thing. A week later you see trees 20 feet away with burned leaves. The other thing you learn when you clean canals and lots is that fire is unpredictable. Very. Now imagine real forests with underbrush and 150 feet tall trees.
- nostrademons 8y ago
  Air is a ridiculously bad thermal conductor - it's thermal conductivity is 0.024 W/mK, so to deliver the same heat flux as a 100W light bulb through a meter of still air would require a temperature difference of about 4000 K. Most heat transfer through air occurs through convection (wind). Even then, if you can keep a 5 foot buffer zone of still air between combustible material and the raging inferno, you're fine. This is how you see pictures of scientists standing 5 feet away from a moving lava flow. As the article states, though, it really is all about the embers. If you keep burning material from landing on other combustible material, fire is not going to start. That's why it suggests using non-combustible materials for roofing, avoiding areas where embers can catch, and keeping treetops away from structures.
nradov 8y ago
The building code for high risk fire areas should require roof top sprinkler systems. Those exist but haven't been widely installed. Keeping the roof and exterior walls wet is usually sufficient to keep a building from catching on fire unless the fire is very close and hot.
- s0rce 8y ago
  The house I rent part of has sprinklers on the roof. The owner installed them after the 91 Oakland Hills fire (we're just down the hill a little from the edge of that fire), as a newcomer to California this was somewhat frightening, but seems like a good precaution. Depending on where your water pipes are and how big your house it it doesn't seem like a huge project.
- briandear 8y ago
  Not these current California fires. Anyone who thinks sprinklers will help hasn’t seen this hell-fire inferno up close. The Camp Fire was spreading at up to 80 acres per minute. It grew to 17,000 acres in 5 hours. High risk fire areas should be made lower risk by proper forest management — forest management that has been ridiculously incompetent in California for a long time.
  - rblatz 8y ago
    I've suddenly started hearing the assertion that forest management is incompetent. But I've not really heard any details as to what is actually wrong and what should be done. Can you please elaborate?
    - nostrademons 8y ago
      The other weird part about this assertion is that forests in which the Camp Fire started are federal land (Plumas National Forest), under the responsibility of the Forest Service. So while it's entirely possible that forest management in California has been incompetent, that responsibility lies on the federal government.
    - 8y ago
crazynick4 8y ago
I didn't notice anyone mention shipping container homes. If built with fireproofing in mind (ie the builder refrains from adding any flammable materials to the outside walls), I'd imagine they'd be fairly impervious by default. Granted, they're not very pretty 'by default' (although they can be made so and still remain flame-proof) but as far as practicality/value/safety goes, that is what I would do if I was buying/building a home in a place like CA.
- skybrian 8y ago
  I'm not sure what "fairly impervious" means but this article looks interesting: “We know from the experience of the 2009 Victorian bushfires that some people did perish in what they thought were bushfire shelters that they’d built themselves. Whether it was secondary to a wine cellar or it was some sort of building container, shipping container, they died. And it wasn’t necessarily they died because of fire; they suffocated. The oxygen was extracted out of the bunker because it wasn’t air-tight or the heat essentially killed them.” https://www.gatewaycontainersales.com.au/shipping-containers-for-fire-protection/ https://www.gatewaycontainersales.com.au/shipping-containers...
  - crazynick4 8y ago
    Right, I should have been more specific, you definitely wouldn't want to stay inside if there is a fire outside in hopes that it will insulate you, the containers are definitely not air tight. What I meant is that the interior of the house would have been protected from burning up, so any inanimate things inside would have been safe.
  - Pinckney 8y ago
    Right, you would definitely want some oxygen candles if you were trying to hunker down and ride out a fire. https://en.wikipedia.org/wiki/Chemical_oxygen_generator https://en.wikipedia.org/wiki/Chemical_oxygen_generator
dbcurtis 8y ago
> A house can be thirty feet from an entire forest on fire and never burn down. In zero wind. The fires in Santa Rosa were driven by 60 mph (100 kph) winds. Even 30 mph winds will pick up the top 15 meters of a burning Ponderosa Pine and carry it 400 meters away and start a new fire. After the Santa Rosa fires I saw newspaper photos of melted barbeque grills. A fire hot enough to melt cast iron is going to light or melt any roofing material I can think of.
- xenadu02 8y ago
  No one is claiming you can fireproof a house; did you even look at the link? With some simple actions you can change the odds of 100% of homes burning down to 10-50%. This isn’t made up, these are facts proven by evidence and experiment. Your comment is like saying no one should bother building basements in tornado country because a strong F5 will kill you anyway. The vast majority of tornadoes aren’t strong F5s so taking some precautions absolutely will save lives and property. The biggest ones are: - fire-resistant roofing; the vast majority of homes that burn in these evens are set on fire by embers long before the fire line even gets close, which makes firefighting efforts basically pointless - fire-resistant siding; if a fire is near this makes it much less likely that the siding will catch from brief contact or by being heated to its ignition point. If the side walls catch the house is a goner. - keep tree tops 30-60 ft away from structures. Fires often leap from treetop to treetop, then from there to the structure. - use non-flammable landscaping near the home.
  - briandear 8y ago
    Keep tree tops 30-60 feet away from structures is certainly good advice, but the environmental extremists are virulently opposed to any efforts to permit homeowners from being able to do that sort of tree management on their own property. Here is a page from such a group attempting to oppose a measure that would allow private citizens to cut down trees on their own land, if that land is under 300 acres in area: http://winewaterwatch.org/2018/08/kill-ab-426-allowing-road-building-and-cutting-of-large-trees-without-a-permit/ http://winewaterwatch.org/2018/08/kill-ab-426-allowing-road-...
nixpulvis 8y ago
My best friend in high school lost his house to a fire in the mountains of CO. The house was made out of clays and other highly fire resistant materials, to the point it was designated the safe house for the fire crew of the area... when the four mile canyon fire swept through it was so hot it even melted all the metals like copper and steel. There was nothing left. I'm sure there are lots of ways to build houses to resist fire more, and we should be doing that, but "basically impervious" is an overstatement.
- thaumasiotes 8y ago
  > The house was made out of clays > when the four mile canyon fire swept through it was so hot it even melted all the metals like copper and steel. There was nothing left. But exposing clay to really hot fire just hardens it into fired clay. Hence the term. What happened there?
  - zhengyi13 8y ago
    Fire resistance would be orthogonal to structural stability, I expect. If the steel beams melt, and they're what's holding up the clay, clay/structure can certainly collapse, even if you can still say nothing burned, as such.
    - deleted 8y ago
      [deleted]
  - chrismorgan 8y ago
    FYI, if you expose clay to really really hot fire, it still melts. A mere 4,000°C will even melt everything in https://en.wikipedia.org/wiki/Ultra-high-temperature_ceramics https://en.wikipedia.org/wiki/Ultra-high-temperature_ceramic.... I have no real concept of the sorts of heats involved in fires like the one described above. But even if the clay isn’t melting, it’s fun to know that ceramics aren’t magical non-melting, non-burning things—they just require unusually much, typically impractically much, heat to achieve it.
tlrobinson 8y ago
Some new housing developments in wildland-urban interfaces are built and maintained such that it's considered safer to "shelter-in-place" than evacuate in some circumstances. Here's a document explaining Rancho Santa Fe's approach (PDF): https://www.rsf-fire.org/wp-content/uploads/2016/09/SIP_for_web.pdf https://www.rsf-fire.org/wp-content/uploads/2016/09/SIP_for_... Some of the requirements: * Boxed or Heavy Timber Eaves * Non‐Combustible (Class‐A) Roofing * Fire Sprinklers * Ember‐Resistant Vents * Landscaping * Roadway Width * Defensible Space * Spark Arrestors * Tempered Windows * Water Supply
- londons_explore 8y ago
  > safer to "shelter-in-place" https://en.wikipedia.org/wiki/Grenfell_Tower_fire https://en.wikipedia.org/wiki/Grenfell_Tower_fire
abandonliberty 8y ago
Trees are a crop that have a nasty habit of burning. Firefighting is another example of government subsidy for industry.

athenot 8y ago

That's the same problem in the South East with tornadoes. They happen nearly every week (in summer) and can destroy neighborhoods. Yet we build lightweight framed houses and rely on insurance because the overall odds are low.

danielvf 8y ago
I agree with your general point. Though we are talking many, many orders of magnitude less damage from tornadoes in the Southeast when compared with California forrest fires. My state gets an average of 20 per year, and almost all of these hit uninhabited areas. If a tornado destroys four houses, it makes state news.
- js2 8y ago
  A better comparison is hurricane prone locations. After Hurricane Andrew in 1994, Florida conpletely revised its building codes to require homes to withstand a major hurricane. It’s possible to build a home on the beach to even withstand a catastrophic hurricane, but at possibly double the construction cost. https://www.nytimes.com/2018/10/14/us/hurricane-michael-florida-mexico-beach-house.amp.html https://www.nytimes.com/2018/10/14/us/hurricane-michael-flor... I recall after there were bad fires in the Everglades many years ago there had been some work to build a foam that could be sprayed on a home to protect it in advance of an approaching fire. I think the person who came up with the idea was inspired by the amount of liquid diapers can hold. I wonder what came of that. Edit: http://www.spokesman.com/stories/2006/jul/19/gel-inspired-by-diapers-may-be-firefighting-tool/ http://www.spokesman.com/stories/2006/jul/19/gel-inspired-by...
  - Klathmon 8y ago
    I know some people in South Carolina whose beach house (on stilts and everything) withstood Irma just fine, however it had to be demolished because the beach had eroded enough that it was basically over the ocean now, and it was infeasible for them to dump enough sand there to have it be over dry land again. It's absolutely possible to build solid safe housing from most natural disasters, but it costs money, and often a lot of it.
cortesoft 8y ago
I mean, are we sure that isn’t the right choice? Depending on the difference in cost and probabilities, it might make economic sense to act this way.
- neilc 8y ago
  "Insurance policies for extreme weather-related losses -- especially for floods and for coastal wind damage associated with hurricanes -- are not priced to reflect the real risk ... as a result of government intervention in property insurance markets, through either rate regulation or direct government provision of subsidized insurance, private markets no longer generate price signals regarding the cost of living in severe-weather regions." https://repository.law.umich.edu/cgi/viewcontent.cgi?article=2751&context=articles https://repository.law.umich.edu/cgi/viewcontent.cgi?article...
pixl97 8y ago
Tornadoes are rather improbable at any one particular spot. Wildfire occurs at regular intervals.
- rconti 8y ago
  Pretty much every wildfire I remember since I moved to CA has happened in a place that hasn't burned before. I'm not sure your theory holds up. In particular, because a truly burnt-out area is VERY unlikely to burn again any time soon.
  - pixl97 8y ago
    This is why we use data and not your memory.

iambateman 8y ago

That 99PI episode was one of their best. The image of a mudslide happening because of denuded mountains was terrifying. I’m reading antifragile right now and he’s talking about systems which improve with a certain amount of volatility and stress. It seems forests are “antifragile” on their own, and our efforts may in fact introduce fragility.

curiousgal 8y ago
>I’m reading antifragile right now I commend you for that, I just find his writing style to be so annoying that I can't even finish reading a simple article of his.
- claytoneast 8y ago
  His books are less grating than his short pieces.
  - stouset 8y ago
    They really aren’t.
- iambateman 8y ago
  Totally agree. I lived with a guy from the Middle East for several years, and it actually helps to imagine his voice when I read Taleb.
gowld 8y ago
Seems obvious that if you expose a system to stress, whatever survives will be stress-proof; while if you hide stress from a system, it's a disaster waiting to happen. Same story with allergy immunities and used cars.
- darkerside 8y ago
  What's the used cars example?

dbetteridge 8y ago

See also http://www.as3959.com.au http://www.as3959.com.au And the australian BAL standard for bushfire rating houses

roel_v 8y ago
I'm working in an Australian research project (for the Bushfires Crown Research Center) in which we're modeling risk, from bushfires but also earthquakes and flooding, using (amongst others) upgrading BAL levels as an intervention option. It's incredible how little is known about bushfire modeling at scales that are relevant for policy making, our work is met with a a lot of interest at e.g. firefighter's conferences. The crux of the issue is though (from a policy perspective) that defending against low recurrance interval events is most cost effectively done by restrictive zoning, which is (politically) a very hard sell. Observed preference is that people actually prefer band aids over real solutions. It's a hard problem.

Amezarak 8y ago

The article doesn't mention it, but controlled burns are actually a regular occurrence in the east and southeast US. I always assumed it was some decision by the Californian state government to not do so. The rest of the country is not stuck in the mindset described in the article. Fires are necessary for ecological reasons. You can either start them on purpose and control them, or you can wait until they happen anyway and watch them get totally out of control. Exacerbating the situation, I heard on NPR this morning that some POAs in California forbid cutting down trees on your property. Something has to change. Even if you put a complete stop to human-caused fires somehow (not possible) and stop climate change tomorrow, you will still have fires from lightning strikes, etc. You can either thin forests and underbrush (incredibly labor intensive) or you can have controlled burns.

sgc 8y ago
I have not heard of extensive controlled burns in any western state. It is just too large and the forests here burn too hot and fast in terrain that is too rugged. Of course there are some controlled burns in California and other states, but the large scale burns required are not practical by any measure. California is considered to have one of the most advanced firefighting forces in the world. They inform the fire control decisions, and know the importance of controlled burns. Maybe it is just a tougher nut to crack rather than assumed incompetence?
- Amezarak 8y ago
  > I have not heard of extensive controlled burns in any western state. It is just too large and the forests here burn too hot and fast ...Because of the lack of controlled burns combined with weather conditions. California is not larger than the eastern US. We do very large controlled burns here in rugged terrain. As far as I can see, it's a lack of political will and funding, combined with the reality that it's gone so long that its much more difficult than it should be. There are a few prescribed burns done in California, they're just not anywhere near the necessary scale. California can either bite the bullet now and dramatically increase the number and area of controlled burns, or watch as things get worse and worse. There is no alternative. I'll repeat again: fires are a natural part of the ecology, with or without human intervention. You can either do it yourself and lessen the impact, or wait for nature to do it and have regular disasters. EDIT: Just to get a sense of scale, the southeast burns eight million acres in prescribed burns annually. The west burns about three million. California looks to be only in the tens of thousands. The Camp fire has burned approximately 138,000 acres at the last report I can find. http://www.stateforesters.org/sites/default/files/publication-documents/2015%20Prescribed%20Fire%20Use%20Survey%20Report.pdf http://www.stateforesters.org/sites/default/files/publicatio...

Cthulhu_ 8y ago

> A house can be thirty feet from an entire forest on fire and never burn down. That test in Canada seems to have been done under pretty much zero wind conditions though; the California ones (as also mentioned in the article) deal with high winds as well.

microcolonel 8y ago
Add in some sort of tarp, maybe. If you don't have whole rows of houses on fire at the same time, you can actually fight those fires.
fouc 8y ago
The linked article mentions a 100 feet buffer zone, perhaps to take that into account.
- deleted 8y ago
  [deleted]
- asah 8y ago
  These does are affecting urban areas of California, not just wilderness. 100 feet of urban California real estate costs substantially more than the house - houses are often built right up to the property line, and lots are measured in sqft, not acres.
  - gnud 8y ago
    Presumably, if space is that expensive, there's not vegetation next to your house, but another house.
  - nostrademons 8y ago
    The article mentions that as a problem. Dense urban areas have a compensating advantage, though: it's much more economically efficient to set up a firebreak and prevent the fire from reaching 100,000 residents in a densely-packed neighborhood, than it is to set up a perimeter around the one wealthy person's home built in the middle of the forest. The article seems to be suggest (but doesn't explicitly state) a policy like this: "Use public resources to provide a fire protection around the urban growth boundary of major cities, but if you're a homeowner outside that boundary, you're on your own. Design your structure to survive a fire in the surrounding wilderness. We won't suppress fires within the wilderness anymore." In other words, instead of shooting for containment, where the firefighters attempt to control the size of the fire and eventually put it out, they just let the wilderness burn periodically and protect habitation. The added benefit of this is that once the brush is cleared out, future wildfires will be less strong, since there's less fuel. Also makes sense in economic free-market terms, where public resources are used only when they can defend many properties at much lower cost than the property owners defending them themselves, and property owners who are not situated to benefit from these efficiencies of scale are responsible for defending their own property.

gowld 8y ago

If an individual house can fireproof itself, than it should fall out of insurance rather easily -- if you want to save $1000/yr or something on home insurance, build to the insurance code, or declare that you are happy paying a higher insurance rate.

ortusdux 8y ago

Great episode. I talked to a friend that is an environmental scientist/forester about it. She is doing more and more fire risk surveys for homeowners. She said their portrayal of the situation was very accurate. Another relevant podcast episode is this one from planet money: https://www.npr.org/sections/money/2018/02/16/586600540/episode-825-who-started-the-wildfire https://www.npr.org/sections/money/2018/02/16/586600540/epis... They explore wildfire investigations and the legal fallout. It is a great explanation of why PG&E's stock lost 1/3 of its value.

onetimemanytime 8y ago

>>A house can be thirty feet from an entire forest on fire and never burn down. We learned this through hardcore experiments in Canada where they built homes to test and lit forests on fire nearby. Fires in CA apparently went as high as 300 feet (~100m) so no, that would not have helped. Heat alone, with zero wind would probably melt everything with xx meters. If they want to build, don't build in forests or clean out a zone and build a 50-100m buffer. If it was not burned today, it will be burned tomorrow.

fouc 8y ago
Height doesn't necessarily imply width. The linked article does mention a 100 feet buffer zone.
- onetimemanytime 8y ago
  width or not means that there's a LOT of material to be burned and to collapse into the next lot. I've burned wheat fields after 90% of straw was removed and I can tell you that in certain days it rises to 10 feet and you cannot stay close to it, it's unbearable. Not necessarily flames but heat, that barely visible thing. A week later you see trees 20 feet away with burned leaves. The other thing you learn when you clean canals and lots is that fire is unpredictable. Very. Now imagine real forests with underbrush and 150 feet tall trees.
nostrademons 8y ago
Air is a ridiculously bad thermal conductor - it's thermal conductivity is 0.024 W/mK, so to deliver the same heat flux as a 100W light bulb through a meter of still air would require a temperature difference of about 4000 K. Most heat transfer through air occurs through convection (wind). Even then, if you can keep a 5 foot buffer zone of still air between combustible material and the raging inferno, you're fine. This is how you see pictures of scientists standing 5 feet away from a moving lava flow. As the article states, though, it really is all about the embers. If you keep burning material from landing on other combustible material, fire is not going to start. That's why it suggests using non-combustible materials for roofing, avoiding areas where embers can catch, and keeping treetops away from structures.

nradov 8y ago

The building code for high risk fire areas should require roof top sprinkler systems. Those exist but haven't been widely installed. Keeping the roof and exterior walls wet is usually sufficient to keep a building from catching on fire unless the fire is very close and hot.

s0rce 8y ago
The house I rent part of has sprinklers on the roof. The owner installed them after the 91 Oakland Hills fire (we're just down the hill a little from the edge of that fire), as a newcomer to California this was somewhat frightening, but seems like a good precaution. Depending on where your water pipes are and how big your house it it doesn't seem like a huge project.
briandear 8y ago
Not these current California fires. Anyone who thinks sprinklers will help hasn’t seen this hell-fire inferno up close. The Camp Fire was spreading at up to 80 acres per minute. It grew to 17,000 acres in 5 hours. High risk fire areas should be made lower risk by proper forest management — forest management that has been ridiculously incompetent in California for a long time.
- rblatz 8y ago
  I've suddenly started hearing the assertion that forest management is incompetent. But I've not really heard any details as to what is actually wrong and what should be done. Can you please elaborate?
  - nostrademons 8y ago
    The other weird part about this assertion is that forests in which the Camp Fire started are federal land (Plumas National Forest), under the responsibility of the Forest Service. So while it's entirely possible that forest management in California has been incompetent, that responsibility lies on the federal government.
  - 8y ago

crazynick4 8y ago

I didn't notice anyone mention shipping container homes. If built with fireproofing in mind (ie the builder refrains from adding any flammable materials to the outside walls), I'd imagine they'd be fairly impervious by default. Granted, they're not very pretty 'by default' (although they can be made so and still remain flame-proof) but as far as practicality/value/safety goes, that is what I would do if I was buying/building a home in a place like CA.

skybrian 8y ago
I'm not sure what "fairly impervious" means but this article looks interesting: “We know from the experience of the 2009 Victorian bushfires that some people did perish in what they thought were bushfire shelters that they’d built themselves. Whether it was secondary to a wine cellar or it was some sort of building container, shipping container, they died. And it wasn’t necessarily they died because of fire; they suffocated. The oxygen was extracted out of the bunker because it wasn’t air-tight or the heat essentially killed them.” https://www.gatewaycontainersales.com.au/shipping-containers-for-fire-protection/ https://www.gatewaycontainersales.com.au/shipping-containers...
- crazynick4 8y ago
  Right, I should have been more specific, you definitely wouldn't want to stay inside if there is a fire outside in hopes that it will insulate you, the containers are definitely not air tight. What I meant is that the interior of the house would have been protected from burning up, so any inanimate things inside would have been safe.
- Pinckney 8y ago
  Right, you would definitely want some oxygen candles if you were trying to hunker down and ride out a fire. https://en.wikipedia.org/wiki/Chemical_oxygen_generator https://en.wikipedia.org/wiki/Chemical_oxygen_generator

dbcurtis 8y ago

> A house can be thirty feet from an entire forest on fire and never burn down. In zero wind. The fires in Santa Rosa were driven by 60 mph (100 kph) winds. Even 30 mph winds will pick up the top 15 meters of a burning Ponderosa Pine and carry it 400 meters away and start a new fire. After the Santa Rosa fires I saw newspaper photos of melted barbeque grills. A fire hot enough to melt cast iron is going to light or melt any roofing material I can think of.

xenadu02 8y ago
No one is claiming you can fireproof a house; did you even look at the link? With some simple actions you can change the odds of 100% of homes burning down to 10-50%. This isn’t made up, these are facts proven by evidence and experiment. Your comment is like saying no one should bother building basements in tornado country because a strong F5 will kill you anyway. The vast majority of tornadoes aren’t strong F5s so taking some precautions absolutely will save lives and property. The biggest ones are: - fire-resistant roofing; the vast majority of homes that burn in these evens are set on fire by embers long before the fire line even gets close, which makes firefighting efforts basically pointless - fire-resistant siding; if a fire is near this makes it much less likely that the siding will catch from brief contact or by being heated to its ignition point. If the side walls catch the house is a goner. - keep tree tops 30-60 ft away from structures. Fires often leap from treetop to treetop, then from there to the structure. - use non-flammable landscaping near the home.
- briandear 8y ago
  Keep tree tops 30-60 feet away from structures is certainly good advice, but the environmental extremists are virulently opposed to any efforts to permit homeowners from being able to do that sort of tree management on their own property. Here is a page from such a group attempting to oppose a measure that would allow private citizens to cut down trees on their own land, if that land is under 300 acres in area: http://winewaterwatch.org/2018/08/kill-ab-426-allowing-road-building-and-cutting-of-large-trees-without-a-permit/ http://winewaterwatch.org/2018/08/kill-ab-426-allowing-road-...

nixpulvis 8y ago

My best friend in high school lost his house to a fire in the mountains of CO. The house was made out of clays and other highly fire resistant materials, to the point it was designated the safe house for the fire crew of the area... when the four mile canyon fire swept through it was so hot it even melted all the metals like copper and steel. There was nothing left. I'm sure there are lots of ways to build houses to resist fire more, and we should be doing that, but "basically impervious" is an overstatement.

thaumasiotes 8y ago
> The house was made out of clays > when the four mile canyon fire swept through it was so hot it even melted all the metals like copper and steel. There was nothing left. But exposing clay to really hot fire just hardens it into fired clay. Hence the term. What happened there?
- zhengyi13 8y ago
  Fire resistance would be orthogonal to structural stability, I expect. If the steel beams melt, and they're what's holding up the clay, clay/structure can certainly collapse, even if you can still say nothing burned, as such.
  - deleted 8y ago
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- chrismorgan 8y ago
  FYI, if you expose clay to really really hot fire, it still melts. A mere 4,000°C will even melt everything in https://en.wikipedia.org/wiki/Ultra-high-temperature_ceramics https://en.wikipedia.org/wiki/Ultra-high-temperature_ceramic.... I have no real concept of the sorts of heats involved in fires like the one described above. But even if the clay isn’t melting, it’s fun to know that ceramics aren’t magical non-melting, non-burning things—they just require unusually much, typically impractically much, heat to achieve it.

tlrobinson 8y ago

Some new housing developments in wildland-urban interfaces are built and maintained such that it's considered safer to "shelter-in-place" than evacuate in some circumstances. Here's a document explaining Rancho Santa Fe's approach (PDF): https://www.rsf-fire.org/wp-content/uploads/2016/09/SIP_for_web.pdf https://www.rsf-fire.org/wp-content/uploads/2016/09/SIP_for_... Some of the requirements: * Boxed or Heavy Timber Eaves * Non‐Combustible (Class‐A) Roofing * Fire Sprinklers * Ember‐Resistant Vents * Landscaping * Roadway Width * Defensible Space * Spark Arrestors * Tempered Windows * Water Supply

londons_explore 8y ago
> safer to "shelter-in-place" https://en.wikipedia.org/wiki/Grenfell_Tower_fire https://en.wikipedia.org/wiki/Grenfell_Tower_fire

abandonliberty 8y ago

Trees are a crop that have a nasty habit of burning. Firefighting is another example of government subsidy for industry.