California fires: specific architectural qu -anyone know? architects? builders?

[Ineedtogetoutmorereally]

I was very shocked by the pictures of the residential areas showing nothing left at all.

I would expect aftermath of a big wild fire to look more like this:

https://nypost.com/2025/01/08/us-news/before-and-after-pics-show-complete-devastation-of-la-wildfires-photos/#8

with basic brick work, metal features - joists, balconys still intact. These are not fires like 9/11 where you have high combustion airline fuel for example that raises the temperature much higher than a normal fire.

Instead the pictures of the residential areas look like this:

https://i.dailymail.co.uk/1s/2025/01/08/23/93889077-14264179-image-a-179_1736379820030.jpg

This is one example but on the news they were showing swaths of areas with nothing left except a bit of fencing and the odd chimney breast.

So my question is - why is this? what do they build houses out of in this area/in California/USA? is there a trend to not use bricks? what do they use? is this part of the reason there is just nothing left at all of most house structures?

It seems that it is only older buildings - like that shop front - that have any surviving brick work.

American houses are built of wood and drywall (plasterboard) rather than brick.

As above houses in large parts of the US are not brick construction. Just those chimneys you see left behind.

Additionally California is an earthquake zone as well as a fire zone. Brick houses do not fare well in earthquakes.

I thought it was because of earthquakes

It doesn't make sense to build houses with brick in earthquake-prone areas...

I posted this on another thread:

And, yes, earthquakes are also a reason.

Early European settlers in the US built from wood because it was readily available and inexpensive, so even the east coast and the midwest, with much colder climates, have lots of timber houses, including many that were built in the 1700s, so it's obviously fairly durable. It's also sustainable and renewable - bricks are durable but brickmaking isn't exactly environmentally friendly, and concrete is worse, if anything. It's also lends itself well to insulation while retaining breathability. It's faster and more economical to build from and requires less transport. That said, California, where many of the houses are what are known as Spanish or Santa Fe style does have a much higher percentage of non-timber houses than most states.

I suspect now that the fires have jumped from the more populous areas to the hills, with their bigger, more expensive houses, you'll see more that are built from stucco or bricks.

American houses are built of wood and drywall (plasterboard

Ok - thanks everyone. How very strange that stuff that looks so luxurious and expensive (and is very expensive real estate to buy) is just made of cheap burnable tat.

I thought lots of sky scrapers in Japan are earthquake proof but that its about flexible foundations rather than no metal/brick.

I'm very shocked but it explains why there is nothing there.

Thank you.

I've just googled this a bit more and apparently steel reinforced concrete is what you need with flexible foundations for earthquakes! Weird there is so little metal - even metal beams or joists.

wood/timber isn't necessarily tat and is a good choice in many cases. Older timber houses tend to be very well built. Cheaper, newer ones are often built from lesser materials, just as they often are in the UK.

My BIL is building a house in California using these materials.

It’s costing about $5m…

wood/timber isn't necessarily tat and is a good choice in many cases.

I'm sensing 'many cases' don't include areas prone to fire and big winds. No wonder this has just swept through if it's all wood.

It's incredibly sad and really really frightening. All those people who have lost so much.

Wood is relatively locally sourced and suits breathable homes very well . We like well-ventilated houses. If not wood then concrete would be used, not brick. Concrete isn't breathable and it's ugly.

Many of the houses pre-date the massively rapid increase in severity of climate change, when earthquakes were considered the biggest natural hazard on the West Coast. And as a pp has explained, wood is considered a preferred material in earthquake zones. And then there's the fact that, like in the UK, people buy/build what they can afford. Timber is plentiful, sustainable and renewable, easily available and relatively inexpensive.

Like most things, it's more complicated a decision than it looks at this moment.

Stucco or concrete houses in CA are usually actually very attractive as they're Spanish or Santa Fe style, but they're considerably more expensive to build and buy and, as discussed, don't fare as well in earthquakes.

But I do agree about the general positives of wood houses. We have a very old one (1700s) and it's well insulated with none of the condensation/mould/breathability issues that UK houses often seem to have.

I'm in NZ, which is an extremely shaky place. The houses are similar how English houses used to be built, ie, a timber frame, maybe some sort of infill, and an exterior cladding of brick or weatherboard that hides the frame. Plenty of such houses in England that are centuries old. They last if the materials are good quality and they're maintained (as all houses need to be.)

Are you implying that the flames would not have burnt these houses if they'd been built of brick? Or that they wouldn't have needed rebuilding?

Just talked to DH about this as I was curious. He is a construction PM here in the US.

In California for the last decade or so houses are typically built with a steel structure and some kind of wrapping, because the fire risk has increased so much.

He said the whole thing will still burn other than the steel frame, which would then have to be checked over by a structural engineer before deciding whether to take it down and start again or keep it.

Brick has not been used since the 1930s in Cali because of earthquakes.

Are you implying that the flames would not have burnt these houses if they'd been built of brick? Or that they wouldn't have needed rebuilding?

Not necessarily - although if you look there are some properties (one or two) that have survived intact that have brick/concrete walls or a reinforced concrete.

. I think if they were brick (or reinforced concrete) that there would be some structure remaining so the rebuild would have a base to work from but more importantly, fire wouldn't have spread so quickly and been so devastating.

Wood and plaster will burn fast and tonnes of 'bits' of burning stuff (which is light and will fly easily in wind) is going to start a fire in the next door property much quicker than a burning brick building. Obviously standard stuff like they are so assiduous about in Australia (like keeping a vegetation clear band all the way round the property) and not building so close together makes a difference

but a brick building 1 on fire is not necessarily going to start a fire (even in wind) in brick building no 2 next door.

wood building 1 on fire is definitely going to start a fire in wind in wood building 2 next door.

This house surrounded by a concrete/brick and motar wall survived untouched:

https://x.com/ChasenGreg/status/1877478755091767732

There is little vegetation around the house and it has a tempered glass apparently.

Brick is OK if used just for cladding at low heights in earthquake zones. Plenty of brick cladding in Christchurch. The deaths in the 2011 earthquake there (185) were mostly in two modern office blocks that failed, and most of the rest in Victorian buildings with supporting brick walls that were built by people who didn't understand the risks.

in comparison to other parts of the world they have next to no building regulations in that state - as well as being wood build due to the risk of earthquakes. So you have a situation rather like the great fire of London where the timber structures were very close.