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by nicole_express·2y ago·view on hn ↗
I'd like to see more discussion of the safety impact; I know the article makes the point that fire deaths per capita are lower in Europe, which lacks the requirement, but it also notes that US housing stock is also much more wooden and therefore at higher risk to begin with. (Wood construction is generally a good thing from a sustainability perspective)

Whenever I see this proposed my brain immediately goes to the Grenfell Tower fire in the UK. I guess that may just be an outlier due to the myriad of other causes, but it gives me pause.

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>US housing stock is also much more wooden and therefore at higher risk to begin with.

Fire compromising the structure of a building, or the structure itself burning is almost never the cause of death or injury. The primary killer in structure fires is hydrogen cyanide gas. Wood does emit hydrogen cyanide but the primary source is synthetic materials like upholstered furniture, wall and floor coverings, cabinetry, and other personal belongings.

If you have two houses, one made of gypsum-covered 2x4 walls and the other made of stone and steel and a faulty space heater ignites a sofa or some polyester curtains, the buildings are equally lethal. The hydrogen cyanide will have killed you long before the fire burned through the drywall. Non-flammable walls don't even necessarily slow a fire's spread if synthetic materials are involved. The high heat of by their combustion and their dirty combustion causes flashover which ignites all flammable materials in a given space.

I have been a volunteer firefighter for almost 20 years. I have experienced too many fatalities but none of them have ever burned to death. All victims have been dead due to asphyxiation (CO/CO2) or cyanide poisoning.

The differences in death rates aren't as stark as the author contends (for example 0.2 deaths per fire in Great Britain, 0.3 in the US) and my gut tells me the main differentiation between the US and European deaths is the smaller, more compartmentalized nature of European dwellings (which limits the spread of smoke) coupled with their greater level of urbanization which leads to faster emergency services response (the faster a fire is knocked down the less gas it produces).

Open floorplans kill.

All of that being said, wooden construction does cause more firefighter deaths-- especially if engineered wood is used. But by the time the floor of a house has been weakened enough by a basement fire to fail and kill a firefighter, all of the occupants are already dead.

What are your thoughts on sprinklers in these types of situations? Are they mostly to give people enough time to get out? Do you feel the safety reduction of moving to single stair is offset by requiring sprinkling?

The way I have seen the idea of single-stair multifamily proposed in US was that in areas where zoning requires sprinklers in multifamily dwellings anyway, all the extra hallway space required for the second stairway is an unnecessary burden cost wise for little marginal safety.

There are many types of fires that can be extinguished by sprinklers but their primary function is to give occupants more time to escape.

A common type of fire that has emerged recently is lithium ion battery fires. Some jurisdictions have so many it is an epidemic.

Sprinklers do nothing to combat lithium iron battery fires, other than slowing the growth of secondary fires.

Honestly I don't think secondary exits should be required for small, low-occupancy buildings (that's a problem we solved with fire escapes but they're "ugly") but at the same time I don't think eliminating them would solve any accommodation availability problems.

For example, in the floor plan included in the article, eliminating the secondary egress staircase would add less than 140 square feet (varies by jurisdiction/occupancy but that floor plan looks like 48" wide stairs with 8 12" treads and a 48"*96" landing on each end) to the floor. In the article itself the author (rightly) asserts that adding a single bedroom to the design in a size acceptable to the market requires approximately 180 additional square feet.

So all you'd get are bigger bedrooms and/or closets, or the addition of a single tiny bedroom. Indeed, in the example given in the article it would be almost impossible to add an additional bedroom. But one or both of the apartments could be given palatial bathrooms...

> and the other made of stone and steel

Not to mention european houses also have drywall over the concrete these days, the days of barren concrete or plaster over concrete have been over since at least the 90s.

I've never been to a European house that has drywall over concrete or brick. The only time I see drywall used there is in finished attic areas to cover slanted roof rafters.
Very common here in Norway, at least. Drywall isn't just to create solid surfaces between structural timber, it also helps dampen sound and provide a flat surface for paint. A poured concrete wall is very rough and would require plastering to get a flat, smooth surface, which is more labor-intensive than just drywalling.
Grenfell is what happens when building regulations are poorly enforced.

In principle, each apartment in Grenfell should have been able to burn out completely while the neighbouring units were untouched, so there was no need for a second stair as any evacuation would have been limited to units adjacent rather than the entire population.

What actually happened is that years of neglect had seen firebreaks and bulkheads repeatedly compromised and then a load of flammable cladding added to the outside, because the building industry is basically rotten.

Had the same incident taken place when the building was first constructed, the damage would have been limited to the one apartment.

Which is why the article's call for "reform of defect liability laws that drive insurance costs up for condo developers" makes his whole position deeply suspicious.
Exactly. If modern day advances make single-stair multifamily homes perfectly safe than there's zero reason to give condo developers a free pass for designs that are found to have led to families burning death.
Europe is a lot more sophisticated about both regulation and multi-family housing then we are, I’m not sure we should interpret North America’s quirks as advances.

If they are advances, we might ask to what end: most building and planning code was created with the express purpose of engineering a suburban single-family detached homeowner-driver society, not to create safe or pleasant urbanism.

Keep in mind that Grenfell was the responsibility of the local council. It was not run by eg a multinational corporation, which usually have better management and a commercial reputation to defend (and deep pockets to go after in a law suit).

Big business gets a lot of flak, but they are honestly better on average than small businesses and many local governments institutions.

Unregulated | poorly enforced "big business" is no better and arguably worse.

The crux appears to be adequate resources to enforce standards

> a commercial reputation to defend (and deep pockets to go after in a law suit).

Meanwhile, in "the real world" sufficiently large businesses are routinely silo'd into seperate sub companies and those that are associated with disaster, product liability, deaths, etc are often mysteriously bankrupt or with insufficient funds to meet penalties of pennies on the dollar.

If you do that siloing, you don't benefit from reputation, yes.
Unfortunately people from the US (including those who have never lived in an apartment or thought about fire regulations before) instinctively get really worried about this whole idea and assume people are just going to get killed.

Happens in this thread and whenever it is brought up in social media. The original article talks about statistics, various extra measures to ensure safety and limiting to buildings 6 stores or less.

But US commentators have trouble getting past their initial reaction. They also do the usual US thing of discounting anything from overseas as "not applicable to US conditions".

I think there is some of that certainly, but it's also worth being cautious anytime a developer says they want to abandon fire codes that were put in place to save human lives so that they can add greater density housing. Fire codes got where they are in part because developers were fine with packing people into unsafe housing situations. Let's not let our guard down entirely now.
>that were put in place to save human lives

There's an assumption here that the code was put in place to save lives. There's a whole lot of regulation that exists simply to make it difficult to build. Lots of people profit when housing is scarce (or unavailable to certain demographics), and want to keep it that way.

It is always worth asking what the point of a regulation is, and whether it accomplishes the thing it claims to be trying to accomplish.

All safety regulations are written in blood.
I totally agree with you that it's definitely instinctive. The article has a link to mass timber construction for fire officials. Coincidentally there is an office building near me with mass timber structure but whenever I tell people about it, they instinctively think of it as less safe than steel and concrete.
Having lived in both places - Italy and the US - I think it's a natural question.

The answer I've heard that makes sense, is that if you do this in US buildings you need decent fire suppression systems even if those bump the price.

But it's well worth doing in terms of making more types of nice buildings viable.

You could just add that as an option to the housing regulation:

Either build in the traditional American style out of wood, or (new option) build out of stone and add a robust fire suppression system, but in return we let you get away with a single staircase and other features that increase density.

I also have an instinct to avoid standing where I could fall a long way - it's probably a good instinct. You haven't provided evidence that the instinct regarding fire safety in single-stair buildings is flawed.
It's not an instinct, it's a gut reaction to change. The evidence is that people aren't burning to death in Europe.
The intention of the double stairwell requirement, is that you are not supposed to have your access point to the stairwell by an obstruction, and there should be a maximum access time to the stairwell.

One notable requirement of single-stair buildings where they are legal in the US, is that

1. the height is generally determined by the height of the fire ladders available, providing a second means of egress

2. the single stair requirement usually only applies to buildings that have a low maximum units per floor. In Seattle where they are legal, this is four units. At four units a floor, your front door directly opens feet away from the stairwell, and having a second staircase a sufficient distance away would be hard to fit in the floor plan.

> 1. the height is generally determined by the height of the fire ladders available, providing a second means of egress

This is an interesting requirement and makes me wonder if some of the need for two staircases comes from the proximity - or lack thereof - to fire services. I'd be sitting in a burning home for a long time if I had to wait for a fire ladder.

A lot of the requirements make sense in bigger buildings. It's not easy to evacuate a large office building taking up a city block using only ladders. And some of it is reactive; for example, there is a distance separation requirement for stairwells, because during 9/11 the three North Tower stairwells were only 70 feet apart and enclosed only with gypsum, so they were all severed on impact, dooming the people above the impact zone. But none of this is really relevant for a building with six floors and 24 units total.

The American city topology is basically office towers surrounded by single family homes; in the midcentury we demolished a lot of the in-between building stock, which is now referred to by urbanists as the "missing middle". Compare this to Europe or Japan which is largely buildings in between those sizes.

Even Singapore has lots of those middle sized buildings missing from the US.
Ground fire ladders are about 35’ max. Aerial apparatus (trucks/quints) around the US are normally around 80-110 feet in length.

My current tower rig is 85’, our next will be 105.

Consider that is ladder length and the “true” height is really a hypotenuse on a right triangle with one side the building.

We can generally reach most of our properties just fine, as our tallest is about 5 stories. However there are some across a river with access harder in front, and a ladder across the river is the way to go.

I think in Japanese apartment buildings they’re all required to have their own rope ladder? Since you go from balcony to balcony they don’t even have to be very long.
also fire suppression system (sprinklers) and pressurized stairwells are mandated.
And fireproof walls between units. It takes a long time for a fire to penetrate two layers of drywall.
The "Well there's your problem" podcast did an episode on 'five over ones' (five stories of wood over one concrete) and touched on this - IIRC they were most likely to burn down during construction when the fire suppression wasn't installed and active yet.
They also did a more in-depth episode on Grenfell, which touched on a lot of the same issues, except Grenfell was (a) taller and (b) occupied.
> Wood construction is generally a good thing from a sustainability perspective

This is something a lot of people get confused about^. To summarize, each ton of wood used in constructions takes approx 1 ton of CO2 out of the atmosphere (cellulose is basically solidified carbon and oxygen), whereas each ton of concrete used in construction puts approx 100kg of C02 into the atmosphere.

^ "You're cutting down treeees, oh the humanity!"

How does that compare to leaving the trees grow, say, 25 more years? You’re only comparing the action of using them in construction.
The density of managed forests would not allow for that much growth across all the trees. Some would get larger, others would stagnate. Better to chop them all and replace with a fresh batch that will all be scrubbing.

The folks managing these forests are in the business of selling as much solidified CO2 as possible every single year, if there was a better way to do it I'm sure they would.

The new construction single-staircase building in NYC that I used to live in was metal and concrete framed, fitted with sprinklers throughout, and had double fire doors separating each apartment from the (all tile/metal/concrete) staircase with little vestibules. It didn’t give me pause in the slightest, really I felt like it was safer from a fire perspective than a typical wood frame single family home, or an older building with a rickety old fire escape.
> but it also notes that US housing stock is also much more wooden and therefore at higher risk to begin with. (Wood construction is generally a good thing from a sustainability perspective)

So if we really care about fire safety, shouldn't we be regulating more effective mitigations to protect these wooden buildings, rather than the two stair aspect?

Pointing out that there's a bigger risk factor than single stair has a natural conclusion.

However, I have become so jaded that I no longer believe that people advocating for two stair cases actually care about fire safety, because of their lack of concern about wooden structure risks.

Imposing strict, burdensome, and hardly-useful restrictions on multi-unit housing while ignoring life saving regulations for single unit housing has pretty clear ideological motivations.

> I'd like to see more discussion of the safety impact;

Another concern is building stability, whether or not the actual construction process followed code, whether or not structural maintenance is adequate, & the age of some high rises. Florida recently had a condo collapse. There are many old tall buildings built on shifting water permeable ground in the US.

China has issues with tall buildings as well, particularly in it's river flood plains. It is quite surreal to see an entire high-rise being carried down a river. Look it up.

Edit:

I was unable to find the video with today's search...so here is the video. Apparently there was censorship with the Chinese government over the video.

https://youtu.be/MCC7C5PJrOI?si=TAgIKOYbIpr8VAM0&t=154

A few cities (with wood framed construction) in NA have allowed this for decades with no apparent issues
That's what I'm trying to raise money to do! ;-)

Basically through an analysis of fire loss history combined with open property data. The fire engineering field hasn't traditionally had access to great data, for a few different reasons, but now the data is actually potentially available to answer the question – but it does need a bit of time and investment.

(I'm the author of the article.)

I’m curious: is there room for a middle ground involving non-enclosed fire escapes? How useful are these?
> (Wood construction is generally a good thing from a sustainability perspective)

I don't really see how wood is more sustainable than eg brick or even steel and glass?

> Whenever I see this proposed my brain immediately goes to the Grenfell Tower fire in the UK. I guess that may just be an outlier due to the myriad of other causes, but it gives me pause.

You should look at statistics instead of single lurid anecdata. In any case, Grenfell Tower is a nice illustration of how when government provides services like housing, they don't magically provide safety. (Funnily enough, people usually try to spin that tower fire as some failure of the market, when the estate was managed by the local council.)

> I know the article makes the point that fire deaths per capita are lower in Europe, which lacks the requirement, but it also notes that US housing stock is also much more wooden and therefore at higher risk to begin with.

Btw, this might suggest to change the regulation so that you can either follow the existing US regulations when building with wood; or you get allowed more density and single-stairs etc, when building with whatever they use in Europe.

Wood captures carbon within it and has minimal energy cost compared to steel, glass and brick. Lumber can also be regrown.

So highly sustainable from a global warming perspective at least.

Steel can be recycled. And we are sitting on a giant ball of matter, so making more bricks or glass is easy. (Glass can be recycled, but it's not really worth it.)

You are right that wood captures carbon. But you have to think about the opportunity costs: the same land that you use to slowly grow your wood could be used to eg run wind turbines or solar panels to replace fossil fuels. (You could also stick a nuclear power plant on that land to replace even more fossil fuels. But on the margin, nuclear isn't really limited by the available land but by red tape and permissions. So adding a bit more land won't make the nuclear industry produce more energy.)

You'd have to run the numbers, it's not obvious to me which effect dominates. Probably also depends on how well wood grows in your climate, and how sunny and windy it is. And what else you could grow on that land.

Speculation: I suspect that emissions during construction will be relatively small fry, compared to the impact of density. Eg re-inforced concrete allows denser living (by building taller than wood, and by allowing single-stairs to be still firesafe, etc), and density tends to lower per capita CO2.

Of course, rural settings won't make use of the possibility of density. So for them it's just about the first order effects.

Fire escapes are still a thing, right??
Fire escapes haven't been a thing in a long, long time. Not in new construction.

Older buildings only.

I guess I've lived in old, old buildings :/
Specifically, they were banned in 1968 in New York City.