[friend_Fernando]

The largest power company in CA is in the process of burying its cables.

The risk level is not just affected by proximity to forests. For offshore (Santa Ana) wind events, the riskiest areas are the SW bottom of hills and near canyons. That's where the current LA fires are.

IMO, a better prevention measure would be to not build houses out of sticks. That's already the case for much of the housing in Europe. Alas, here in the US the colonial and cabin aesthetics still win out, even when fire-resistant options aren't more expensive.

Coffey Park in Santa Rosa was destroyed in 2017, and most properties were rebuilt to lower fire-resistance standards.[1] The second little pig just doesn't wanna hear it.

https://wildfiretoday.com/2019/11/19/after-the-tubbs-fire-ho...

[jandrewrogers]

> IMO, a better prevention measure would be to not build houses out of sticks. That's already the case for much of the housing in Europe. Alas, here in the US the colonial and cabin aesthetics still win out, even when fire-resistant options aren't more expensive.

It is not an aesthetic preference, the US used to construct housing like in Europe through the 19th century.

That style of construction was repeatedly catastrophically destroyed by severe earthquakes, killing many people needlessly, and is now illegal in many regions.

The US became strict about seismic safety after the famous 1906 San Francisco earthquake[0]. A few decades earlier, the 1872 Lone Pine earthquake[1] literally flattened entire towns of European-style construction; some of these are now ghost towns that were simply abandoned and never rebuilt. When you see surviving old masonry buildings, they usually have been retroactively refitted with steel frames to make the masonry mostly decorative.

The regions of the US prone to wildfire are also prone to severe earthquakes, so your options are wood or steel frame construction, neither of which is particularly wildfire resistant but at least it won't collapse during a severe earthquake. Many parts of the US also have to engineer for much higher wind loadings than in Europe.

You can build masonry buildings that meet the seismic standard but that requires a lot of steel and is expensive. Where I live, all modern construction is required to survive a M8.5 earthquake; I've never seen a house in Europe engineered to that standard.

[0] https://en.wikipedia.org/wiki/1906_San_Francisco_earthquake

[1] https://en.wikipedia.org/wiki/1872_Owens_Valley_earthquake

[friend_Fernando]

Your argument only applies to unreinforced masonry, which is no longer allowed by code in seismically-prone areas. For fire resistance you can use reinforced concrete, steel or aluminum framing, or wood framing with non-combustible walls. Or even go exotic with various prefab options and 3D printing.

As for the higher cost, this has become mostly an urban myth. In regions with low construction costs such as the South or the Midwest ($130-180/sqft,) the cost difference is minimal. In areas with high construction costs such as CA ($200-700/sqft,) the difference is either immaterial or negative (thanks to the insurance savings.)

[jandrewrogers]

My argument applies to reinforced masonry as well. You seem to be operating from a naive model of what is required to prevent combustion of buildings. We already use non-flammable walls in a lot of places; it is a speed bump for a serious fire without a lot of additional mitigations.

Most typical reinforced masonry will fail during a severe earthquake, for which there is ample empirical evidence. The cost to reinforce masonry to e.g. a M8.5 standard is not small. The quantity of rebar, ties, etc required is expensive in both time and material. It isn’t cheap nor does the labor exist at the scale required.

I actually live in exotic construction, designed for extreme seismic and wind loads. Lots of steel, not much concrete, and extremely fire resistant (even though that isn’t a requirement here) but much cheaper to build and more seismic resistant (in theory) than reinforced concrete, which is what it replaces (its raison d’être). No structural wood either, but it wouldn’t be economical to construct a typical house this way.

This is an active area of research. If it was an “urban myth” there wouldn’t be so many engineering firms investing in developing new construction techniques that provide seismic resistance without the cost. If reinforced masonry actually worked in a reasonable way, we’d just use that.

[friend_Fernando]

I live in SF. The vast majority of new construction above 3 stories is reinforced concrete, including many high-rises such as the (infamous) 58-story Millenium Tower.[1] Seismically, modern reinforced concrete performs well.

As I explained in sibling threads, "speed bumps" are the most important thing here in CA. It's not about whether your structure can withstand a 1000-degree fire all around it. It's about whether your structure will set fire to three others within minutes of when it goes up in flames.

[1] https://en.wikipedia.org/wiki/Millennium_Tower_(San_Francisc...

[infecto]

This narrative about building houses out of sticks also rubs me the wrong way. It's an extremely naive take on why it happens. The reason most homes in America are wood framed is really down to economics. Europe does not have as vast of a forest stock for lumber as the US/Canada does. Over time we have specialized in building wood framed homes and because of lumber, its cheaper.

These homes would have been destroyed regardless of building material. The bigger issue is most of these homes have probably not properly gone through fire mitigation steps.

https://www.insurance.ca.gov/01-consumers/200-wrr/Safer-from...

[friend_Fernando]

See sibling posts for the cost argument.

> These homes would have been destroyed regardless of building material.

That's just not the case. Fire-resistant construction might not always help the first house at the subdivision's edge, but it will help the rest. One analogy is control rods in a reactor.

As I said in another post, the problem with firestorms here in CA is the rate of initial spread. We always get massive numbers of destroyed structures all at once, and <25% containment until the winds subside. The ignition source for most of the structures are burning wood-frame structures. Early on, firefighters can only help evacuate people.

[infecto]

I don’t think that is entirely correct in the cost angle but it’s ok.

As I said before the homes are of course an issue but the larger issue is basic fire prevention, not the fact that homes are as you say “built out of twigs”. It is certainly a factor but the more important piece are all the other steps that go before as I linked earlier.

[throwup238]

This was a freak event with record wind speeds so basic fire prevention couldn’t help short of bulldozing every other house in the affected neighborhoods and salting the earth. After the Camp fire and the lightning complex fires, California insurers got really serious about fire insurance inspections and mitigation. Problem is that normal mitigation like setbacks and vulcan vents don’t help when Santa Ana winds send fist sized burning embers for up to a mile in front of the fire. Only really expensive and ecologically problematic measures like external Phos-Chek sprinklers would help in that case, which is what saved a few celebrity hokes in the Palisades.

Only well funded commercial and government campuses like JPL or the Getty can afford the kind of fire suppression measures required to defend against a conflagration of this magnitude.

[mschuster91]

> IMO, a better prevention measure would be to not build houses out of sticks. That's already the case for much of the housing in Europe.

The only thing that helps against is hurricanes and other storm events. Once the fire has blown up the windows and embers (or outright flames) enter the interior, it's game over generally. You might be able to re-use a concrete or brick structure after a large fire, but if the fire ran unchecked until it burned out everything, no chance - concrete will have lost rebar integrity and bricks will have soaked up toxic combustion products.

[friend_Fernando]

Here in CA, it's more about reducing the spreading speed than about the resistance level once the fire gets there. All the large structure fires in recent years spread at breakneck speeds during an offshore wind event. In these cases, all that firefighters can do early on is evacuate people.