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A Wicked Problem – The Second Egress: Building a Code Change (secondegress.ca)
74 points by yeknoda on Jan 9, 2023 | hide | past | favorite | 96 comments



This is the more interesting link outlining the actual problem:

https://secondegress.ca/A-Wicked-Problem


We've changed to that from https://secondegress.ca/Manual-of-Illegal-Floor-Plans, which is also interesting but better as a secondary url. Thanks!


I still fail to understand: is slapping an escape ladder on the side of the house THAT expensive?


Wow, being European and used to single-stairwell multi-story buildings, the North American obsession with fire escapes has always seen weird, and it's super interesting that its codification causes the economy of mid-rises to not work out, which in turn causes the weird housing distribution of North American cities. The "missing middle", that the site is talking about.


Europe is behind on a lot of safety infrastructure compared to the US. You frame it as obsession, but really it's just good policy.

> which in turn causes the weird housing distribution of North American cities.

This is a hilarious misunderstanding of the complex intersection of class divides, race divides, gerrymandering, history (white flight), nimbyism, and for-profit zoning that has led to the current lack of mid-rise affordable housing.


I mean, there's still more people who die in fires in the US than in the EU, thanks mostly thanks to space heaters on 120v/15A circuits and absolutely zero retrofit requirements on anything (what do you mean I can have K&T and a Federal Pacific Panel that does not trip on overcurrent in my house with no GFCI/AFCI protection but every single new circuit I add needs to have those?). The US/Canada have gone too far into "new housing stock needs to be perfect" and not enough into "existing housing stock needs to be retrofitted", because not pissing off landlords and boomer homeowners is a main policy goal.


A cursory search says 3k Americans die in house fires, and 5k Europeans die in house fires per year, so probably EU had more fire deaths per capita. But it's hard to tell because EU doesn't have a FEMA equivalent collecting data on residential fire deaths.

https://www.usfa.fema.gov/statistics/residential-fires/

https://www.europeanfiresafetyalliance.org/our-focus/statist...


Hang on, this article is explicitly about mid-rise buildings and the fire safety of one vs two stairwells in those, so you can't drag up statistics that show combined data for all housing types. I'm assuming a large chunk of those fire deaths are people dying because they accidentally burned down their single-family single-story building. That's completely irrelevant in this case so you have to separate that out.


This sub thread got into the angle of general forced retrofit of new code requirements, and claimed a general loss of life from fires being higher in the US making introduction of facts about fire deaths overall relevant IMO.


The decision to not require retrofitting of existing, undisturbed construction means that new code can evolve more quickly to adopt new technologies or safer methods. If every 15A and 20A residential outlet had to have AFCI protection as of some specified date, I can tell you that date would be sometime still in the future from now. Requiring it only for new construction or new circuits means it could be phased in starting in 1999.


"Now for new construction and retrofit everyone in 10-15 years" would make much more sense. Especially for things like GFCI/AFCI protection which is much more useful in old circuits than new.


> I mean, there's still more people who die in fires in the US than in the EU

False - and it's not even close. Europe has almost a full order of magnitude more death from residential fires than the US - house fires caused 2,620 deaths over 5 years in the US [0] vs ~5000/yr in Europe [1].

[0] https://www.thezebra.com/resources/research/house-fire-stati... [1] https://www.europeanfiresafetyalliance.org/our-focus/statist...


>house fires caused 2,620 deaths over 5 years in the US

Your source says that was 2,620 per year further down in the article:

>House fires cause an average of 2,620 civilian deaths each year.

Given that the EU has a significantly higher population than the US (~500 million, the EU data may or may not have included the UK, vs ~330 million) the per capita statistics end up fairly close.


> You frame it as obsession, but really it's just good policy.

Well, there are alternative ways to reduce the risks presented by a fire in the primary staircase trapping people inside.

For example, good sprinkler coverage of the primary staircase, strict rules prohibiting storing anything flammable below the staircase or running electrical wiring there, compartmentation so there's time for the fire brigade to arrive before a fire can spread between homes, housing options for vulnerable citizens so only able-bodied people have to evacuate via the stairs, and so on.

Of course, many American buildings are made of wood, so it's understandable why American fire codes look different to European ones - and if I had to be in a burning building but could choose the design, an American-style single storey suburban home where every room has a window you can climb out of at ground floor level is hard to beat!


Yep, $1 Million+ homes in the largest job markets in the U.S. are hard to beat!


I think a $100k cabin also meets the specified criteria.


> Europe is behind on a lot of safety infrastructure compared to the US.

That's a rather sweeping statement.

> and for-profit zoning that has led to the current lack of mid-rise affordable housing.

Yes, it's a complicated issue with tons of causes, but what this site is saying is that the requirement for a second stairwell skews the economy of building mid-rises so much that they become unfeasible for developers (In Ontario) even if all the other factors were to be fixed. And so you're stuck with either high-rises or single-story buildings.


white flight, nimbyism

Is it truly unreasonable to want to move away from places where crime is rising and cleanliness and living standards are falling? Isn't it a bit unfair to ascribe that desire to the level of whiteness of a person?


It's a historical fact that got named after its most obvious feature. They were white people.


I struggle with this too, but I find your reduction of a complex topic extremely ignorant and borderline racist. Your phrasing plays into a classic far-right trope.

I do believe there are city people and rural people. Each has a right to choose for themselves. Forcing unwanted change on either group is wrong. Towns and cities should chart their own courses.


Agreed. If we went on calling bad things by the predominant population which engages in negative practices, most people would object.


Well, the Black folks weren't allowed to move to the white areas, regardless of class or income, so even if the story of "that desire" were purely as rosy as you paint it (spoiler: it wasn't), the resulting migration would still be accurately titled "white flight".


Don't get triggered. Nobody is talking about you or calling you a bad person.


> it's just good policy

Is there any empirical data on the safety benefits of a second stairwell?


In the spirit of curiosity - how would you go about measuring that? A counterfactual is almost impossible.

That being said - when in doubt, I favor more regulation for safety, not less.


> how would you go about measuring that?

Death and injury frequencies. Anecdotes of preventable deaths, e.g. where one stairwell was not enough versus where a corridor separating two stairwells became, itself, an obstacle. Drill simulations.

We should have have some basis for the rule. (If we don't, I'd support scrapping it.)


You could measure it by people who perish in structure fires, a metric on which America is far behind Europe.


This got me curious. Best i could find was the CTIF (The International Association of Fire and Rescue Services) [1] and their annual report [2].

Table 1.2 shows a breakdown of fire deaths per 100 fires. US 0.3 France, Germany 0.1 Greece, UK, Belgium 0.2 Poland, Denmark, Slovakia 0.4

So it's a bit of a mixed bag. The reported average was 0.5 (report didn't cover every country). Sadly Canada wasn't in the table.

Japan at 3.8 was a bit of a surprise.

1. https://ctif.org/world-fire-statistics 2. https://ctif.org/sites/default/files/2022-08/CTIF_Report27_E...


You'd need to weigh that against the costs and lost opportunities. If no one can buy an affordable apartment and overengineering is part of the cause, or if many die because of a car-centric culture because you can't built densely enough, that can be a problem.


I'd wager most of the US deaths occur in single-family homes--in basements (illegally housed), or even while sleeping in rooms with plenty of opportunity for egress.


white flight is a pejorative, the correct term is reverse-gentrification


This appears to be a dumb joke but the opposite of gentrification is "disinvestment".


I think it comes from the houses being made out of wood instead of brick. Or at least it seems likely comparing houses in the Netherlands and US. The way houses burn is just totally different.


Yeah, that might be a big part of it. I was shocked to discover how flimsy multi-story houses are constructed in North America compared to what I'm used to.

Every single apartment I've lived in in Stockholm has had a single stairwell, and it's not something I've ever thought about because no-one thinks of it as an issue. But on the other hand, those stairwells are always concrete and stone and marble, and fire regulations forbid you from storing anything in the stairwells or outside your apartment.

Take my current Stockholm apartment, there's a four-storey drop from the balcony to the ground and a single stairwell, which would apparently horrify every North American.

But the walls are concrete. The walls between apartments are concrete or drywall. There's four apartments per landing. The apartment doors are made of steel. And the stairwell is empty and marbled, so there's nothing that can burn in the stairwell, and it's very difficult for fire to spread from one apartment to the others. There's no sprinkler system, but I think there's a fire extinguisher on each landing.

Not a problem.


A lot of new construction in the urban US is similar - once you reach a certain level of density.

I live in a row-style apartment building in NYC built within the last decade, which is 6 floors, 2 apartments per floor, steel frame with concrete floors. There is a single interior stairwell, also all cinderblock. We have restrictions on what can be stored in common space.

NYC categorizes this type of construction as "fireproof" - which basically means that in case of fire, unless the fire is in your unit, it is expected to be safer for you to remain in your apartment and await evacuation than to enter smoke-filled hallways. Any fire is expected to be contained.

The city's other category of dwelling is "non-fireproof", and non-fireproof buildings require multiple forms of egress. You need multiple ways out because the fire is expected to spread.


> The city's other category of dwelling is "non-fireproof", and non-fireproof buildings require multiple forms of egress.

Cool!

That sounds perfectly reasonable to me, and since the site is specifically about the building codes of Ontario, arguing for adapting a building code similar to the one you describe for NYC is probably a much better way of making your case, rather than posting a bunch of artsy floorplans from recent projects in various European cities...


(I think that) Flimsy ~= less likely to fall down in an earthquake. When I moved from Ireland to California I moved into a two storey (1940s?) apartment apparently constructed from drinking straws and toilet paper. But… a few weeks later the area was struck by a significant quake. Part of the freeway fell down. I was woken from sleep by the building swaying and creaking. But it didn’t fall down.

Try your Stockholm apartment in that.


This doesn't make sense.

The US can obviously build earthquake-proof concrete and steel skyscrapers, just look at the entire SF downtown. So if you can do that, why wouldn't you be able to build earthquake-proof midrise buildings out of concrete and steel?

When I lived in SF I was woken one night by an earthquake, the entire 42-story high-rise I was living in was swaying back and forth, but obviously didn't collapse.

Sure, I can see how a wooden construction is a cheaper way to make buildings earthquake-proof, but does it really cost that much to earthquake-proof a mid-rise? Or is it not economically feasible to build mid-rises out of anything but wood in the first place?


Well, because midrise buildings hit a horrible resonance with the frequency of earthquakes and are the type of building most at risk, and because those huge skyscrapers have pendulum counterweights, wheels they roll on 100 ft in the ground, and it just costs way too much to use that tech in a smaller building.


If an apartment is on fire between yours and the stairwell and that fire extends to the hallway, then you’re dead, right? If there was a second stairwell on the opposite side then you’d still be able to escape.

I’m pretty sure sprinklers have been shown to massively increase fire safety.


> and that fire extends to the hallway, then you’re dead, right?

The point is that this can't happen for a number of reasons. The landings in my building are quite small, four doors and a stairwell, it's literally two meters from my apartment door to the stairwell, there are no long corridors. And there's nothing that can burn in the stairwell, it's all concrete and stone and steel. And all the apartment doors are steel as well.

The dangers of apartment fires are mitigated differently, so that there is no need for a second stairwell or fire escape.

And this is something I didn't see on the site, and which is probably where they're a bit wrong and misguided. Just because actual fire statistics are better in Europe than in North America despite allowing single stairwells, it doesn't mean you can remove the requirement from the Ontario building code and everything will be fine and dandy. You have to add all the other things that mitigate fire hazards.


That’s what I am thinking. It’s hard to imagine a scenario where the brick house I grew up in Germany could burn down but my US house would probably burn completely once the wood in the walls has caught fire.


Fire codes aren't the reason that you can't build in most of North America.

NIMBYism, and the cultural obsession with low-density, single-family homes only made possible by car-centric transportation infrastructure is.

Which is also in no small part caused by a financial and tenant rights system that pushes people towards home ownership, instead of renting.


Part of the car-centric infrastructure is fire codes. American towns have lots of fire departments which all refuse to buy smaller European-style fire trucks, and all roads have to be built to fit what they buy.

European buildings are also less likely to be made out of wood, which is good if you care about fire safety that much.


> Part of the car-centric infrastructure is fire codes.

No, it's not. Cheap gas[0], giant freaking interstates, and public transit systems (when they are even present) that are very clearly built for the 'poors' are.

Another 3% to the per-square-foot-cost of building a multi-tenant building aren't the reason that Houston has 12 and 16-lane highways cutting right through the city, or why it takes an hour to travel by bus in Stockton a distance that you could travel in 10 minutes by car.

Fitting fire trucks is a problem for local, last-mile streets[1], not arterials, and availability of arterials (and lack of availability of alternatives) are what plays a large part in how people get around.

[0] Under $3.20/gallon in most of the country, compared to over $7/gallon in most of Europe. Not to mention the double-whammy of generally lower[2] European wages.

[1] Most American suburbs solve the width-of-last-mile-street problem by simply... Not having sidewalks. It's not like there's anywhere you can walk to from them...

[2] Okay, okay, yes, Western European take-home incomes for low-paying jobs tend to be higher than their American counterparts.


I mean I didn't say it was all of it, it's just another small part of it. Those are more important factors, yes, but minor issues by land area are more important if they especially affect urban areas. Parking minimums and setbacks are like that too.

> and public transit systems (when they are even present) that are very clearly built for the 'poors'

This one's funny because it's true, but the way you write it makes it sound disparaging - whereas if you said they were designed for "equity" then everyone would agree that's what it's for and that it's good.

Another way to say it is, American transit planners will happily make a project worse and take longer to build, as long as it reaches poorer communities first.


That last bit about not having anywhere to walk to is a bit of a chicken + egg problem; if you can't walk, then nobody is going to make things to walk to.


They are all chicken-and-egg problems that suck us into the morass of a local maximum. Transit sucks, because people with political pull don't use or prioritize it, so people with political pull don't use it. Gas is cheap so people drive everywhere, so people lobby to keep gas cheap. There's no way to break out of this feedback loop.


3-6 story midrises with multiple staircases are all over the place in the USA, but many of them are on larger lots than seem to be being discussed here for Canada.

For smaller-footprint (multiple buildings per city block), stairwells in opposite corners seems to be the most common pattern. About six to ten units per floor in a rectangle.


There's probably a fire escape somewhere that you haven't noticed. When I lived in a 23-storey building it had a second fire escape stairwell and a fire escape ladder outside next to the garbage chutes. I now live in a 9-storey building and it has a fire escape ladder bolted next to the balconies.


> There's probably a fire escape somewhere that you haven't noticed.

No.


Yes, our obsession with not wanting to burn to death. So weird.

https://en.m.wikipedia.org/wiki/Iroquois_Theatre_fire

Or more recent and relevant, an apartment fire: https://en.m.wikipedia.org/wiki/2022_Bronx_apartment_fire


Do more Western Europeans burn to death than Americans?


I feel this is something you can check yourself and bring back to the thread instead of asking rhetorically, as if it's obvious that they don't.


I'm currently remodeling my house and our contractor recommended adding a fire suppression system as part of the project. I always assumed that would be something I couldnt afford but the quote was pretty reasonable (~2500) I wonder if these kinds of systems, plus advances in other building materials have reduced the risk profile to the point where multiple egress points are no longer needed


Any amount of water you can get onto a fire increases survivability (both in time and number of locations). NFPA 13R is a relatively recent addition to fire code that focuses on making low-rise residential fire sprinklers much cheaper to install and that shows in the price quote you got.

13R allows use of existing plumbing connections. It doesn't require a separate feed from the water main, nor does it require a separate iron pipe network inside the structure. It also doesn't require extensive equipment like some commercial systems do (eg sensing when one sprinkler goes off and using high-pressure to force the whole zone of sprinklers to go off).

> advances in other building materials

Definitely not. You'd think we would require a quick spray-down of boric acid on wood stick construction right after framing. Boric acid (or borax) is an insect repellant, smolder suppressor, and fire retardant when used this way. It would - at minimum - slow the spread of structure fires. It is also dirt cheap. But nope... buildings themselves are just as flammable today as they were 50 years ago. Survivability is worse thanks to so much synthetic fabric and foam giving off really toxic fumes and more or less no requirement to make anything flame resistant.

---

If you want to increase survivability in your own home:

1. If you can afford it have sprinklers installed. In most US states the cost is a lot less than you might think, well under $10k. Usually under $5k. Insurance can't replace lives nor keepsakes. Nor can it repair bodily injury. If you worry about water damage I can promise you repairing it is far cheaper than repairing smoke/fire damage.

2. Have working smoke detectors. Get 10-year sealed lithium ones. The day you install them set a reminder in you phone for 10 years from now to replace them. Install them in the recommended locations.

3. Sleep with your door closed. If you need air, crack a window. If your room doesn't circulate enough from a forced air system shave a bit off the bottom of the door. Experiments show even a cheap cardboard core door can provide 30 minutes of protection from a raging house fire. It blocks most of the smoke. It also greatly slows down heat transfer which reduces flashover risk. I'm not joking - you can find videos on the web where the hallway is a charred black hellscape but the bedding/carpet in a bedroom behind a closed door isn't even slightly blackened.


Would you care to elaborate any more details on the boric acid thing? The way you've put it, it sounds negligent to not do it to any exposed framing.

Got any examples of commercial products? Or suggested concentration for full DIY with off the shelf Borax?


Timbor is one used for insect repellant. Boralife sells pre-treated lumber and your local lumber yard can probably supply you with other brands.

IIRC for fire retardant a 7:3 mix of boric acid and borax dissolved in distilled water (at 80C to speed up dissolution) can be used. Borax reduces flame spread but can cause smoldering while boric acid suppresses smoldering. AFAIK any concentration high enough for flame suppression is plenty to deter insects and prevent fungi/rot.

I can't find anyone selling this as a packaged solution with instructions so I'd suggest doing your own tests before trusting a random HN comment. This is all from memory so don't take my word for it.


Thanks for these reminders! #3 is especially important.


Just curious what the "fire suppression system" is in practice, is it sprinklers or specific fire retardant materials (drywall, shingles etc) used. Also wondering what geo location you are in (in consideration of regional fire risks and codes).

Edit: would assume single/multiple egress points are tied to the human capacity limit for the building but am not an arch/civil engineer


So, the complaint is that they don't want to stick a fire door on the back of new buildings, since it would undermine some architectural design purity or something?


Not really, they are saying that the requirement for a second egress in multi-apartment buildings (which is not only a second fire door, it is also a second stair, etc.) makes too costly/complex mid size buildings.

The first image on this page exemplifies the issue:

https://secondegress.ca/A-Wicked-Problem

https://freight.cargo.site/t/original/i/9b6f13e0414b47f094ad...


I don't understand. I live in a three-story apartment building in San Francisco that has about 20 units (ground floor is retail space, the upper two floors have 10 apartment units each). There's a single entrance and stairwell in my building. However my building also has two fire escapes (one of which is accessible via the hallway, I think the other fire escape is only accessible by certain apartment units) and an additional wooden staircase in the back that leads to the garbage area. I don't know all the zoning laws, but this is an extremely common layout in SF. My building, like many many other buildings in the city, was built in 1906 after the earthquake, and all of the building built in this time period have a very similar style and layout.


It's very common, especially in places like SF, for all the old buildings and neighborhoods that people actually like to be illegal to build if they were new.

Of course, in SF it's practically illegal to build anything under any circumstances if any of your neighbors decide they don't like it.


In the case of a fire where all apartments are occupied (each by two people on average) in your SF apartment, you have in theory 40 people/2 stairs= 20 people each (though it is more likely that there is a "main" stairwell, so that will take - say - 28 people and the other one 12.

In a small multi-apartment block, up to 10-12 apartments (5/6 on 2 floors or 2/3 on 4-5 floors) the single stairs/fire exit will be used by the same amount of people or less.

If you prefer, if you graph it, the function of number of stairs per block depends on number of apartments and the points are:

1=1

2=2

3=2

4=2

5=2 ...

what the author is saying is that the step at 2 apartments is too low, compared to what are the norms in other countries and that these countries have not worse records, statistically, for deaths in fires.

This latter is debatable, as there are so many factors involved such as efficiency of rescue/fire services, type of construction (materials used), height of rooms, sizes of windows, number of floors of the "average" building in any given country (and even local situations, city by city) that it is difficult to do a sensible comparison.


According to the article, it's buildings with 2-4 units per floor that are significantly impacted by this rule. At 10 per floor, your building is a lot larger than the ones the article is talking about.


That sounds fair on the surface, but we manage to build multi-egress buildings all the time in other countries, and if a single stairwell is the only egress a lot of people could die in a fire. Some of these mod-sized buildings are too tall to make jumping out of a window a realistic option. So I’m not really sympathetic to this argument.

Unlike some building codes, this one is directly connected to a life and death issue and we have seen what happens in fires where people can’t get out.


Except what this site says is that counter-intuitively, this policy doesn't save lives, it's actually the opposite:

"Zeidler explains that “this appears to be a reasonable precaution for life safety. However, the life safety of this single stair type in Europe has been equal to, if not better than ours,” due to the fact that the single stair scheme is shared between fewer units."

And that's the thing, entire countries disagree on the necessity of a second stairwell for fire safety, and there's data to back up the position.

But because a lot of people in North America have those (unfounded) fears, the second stairwell is part of the building code, and as a result an entire class of buildings don't get built because the economics don't work out.


> But because a lot of people in North America have those (unfounded) fears, the second stairwell is part of the building code, and as a result an entire class of buildings don't get built because the economics don't work out.

I don't believe the fears are unfounded, and frankly I don't see why anyone should buy what this Zeidler guy is selling -- if what he is saying is true, all it means is that European buildings should also be changed to have multiple egress options for every unit!

Seriously, would you be willing to live on the 6th floor of a building where the only way out in a fire is a single staircase? Don't look at statistics to decide this: even if you would be safe most of the time, it only takes one outlier incident to kill you, so why put yourself in that situation?


>Seriously, would you be willing to live on the 6th floor of a building where the only way out in a fire is a single staircase?

I think the argument is: adding a second staircase means creating a large hallway, which might make it easier for the fire to spread.

I don't see why we shouldn't look at statistics. If something is statistically safer, wouldn't we want that?


I'm siting here pondering how adding a second stairway to a building makes it economically unfeasible. What kinda crappy buildings are you making where the stairway is that substantial to the cost of the construction?

And in low rise buildings, there's usually a LOT of stairways lol. A typic suburban US apartment complex has a half dozen buildings, and each one has maybe 12 apartments and like 4 stairways.


Adding a second stairway typically requires rearranging the building to be double-loaded (having a central hallway with apartments exclusively on either side), which wastes much more space, only allows windows on one side of the apartment, feels like you live in a hotel etc.

https://www.treehugger.com/single-stair-buildings-united-sta...


What's wrong with fire escapes? I see plenty of space to add those to a point access block.


Yeah, it seems to me that we can actually work out the situations involved, and being on the sixth floor of a building with only one fire egress seems undesirable.

Perhaps it can be compensated for with various "either two egresses OR each bedroom must be equipped to be fire proof for X minutes" or something, and bring back hook and ladder trucks (arguably which are not used as much because buildings now have multiple egresses when that tall).


> each bedroom must be equipped to be fire proof for X minutes

This is the kind of absurdly complex regulation that sounds simple, but is a lobbyist's dream. Two exits are easy to know when you've implemented, and easy for regulators to check if you've implemented. A "bedroom" being "fire proof" for X minutes will involve 900 pages of nonsense regulations from which lobbyists have carefully removed anything that will affect their bottom line.

"Each bedroom must be equipped to be fire proof for X minutes" was the type of rule that caused the fire brigades to tell people in Grenfell to stay in their apartments, and even more importantly the type of rule that allowed contractors to claim compliance to was sufficient enough that they could use flammable, shit cladding that was illegal in Europe and the US, and install it incompetently (because if the units were "fireproof," who could care?)


Very good points - and Grenfell is an example as to why these regulations exist; otherwise people would burn to death in "missing middle" housing and nobody would really care much.


I live in Vienna and almost all buildings are single staircases with 4-8 floors. Almost all house fires are in old housing stock. In new concrete apartment buildings it is usually a single apartment that burns out. It is an almost absurd fear compared to eg traffic related deaths.


It’s one of those things that is rare and unlikely, yet is extremely bad when it happens. Kind of like how airline crashes are much rarer than car crashes, but they are also much worse and always make the news.

When you have a 99% chance of things going well, and a 1% chance of things going badly, normally you would feel very safe. But when “things going badly” can mean dozens or hundreds of people dying in a fire, that 1% suddenly looks a lot more serious.


But the article is not about building codes for larger buildings, it is about the building code for small ones exceeding the single family house.


High-rise buildings are a completely different matter.

Besides Grenfell, the same thing (without deaths, thankfully) happened in Milan (very similar issue with aluminium panels on the outside):

https://www.youtube.com/watch?v=iNvbxTMSM5Y

What emerged from both these fires is that some of the "new" materials are far less safe than expected and that the fire brigades simply have no means to pump water at a height more than a few floors (ten-twelve?).


How many fire deaths are worth how much housing? Inaccessibility of housing is tied to economic destitution, homelessness, and other things that directly cause deaths. It's entirely possible for more quality-adjusted life years to be lost in the path that causes less housing to be built.


The thesis isn't particularly clear but what I think they want is a modification to Canadian building code so that structures up to a certain size don't need a second egress. They want that, I think, because that aspect of code makes it hard to design housing that sits in the middle of the scale between single family homes and high rises. That middle tier of housing seems like it could be important if you consider what NIMBY-ism and a shortage of housing is doing to some cities.

I couldn't find out out _why_ a second fire exit makes it hard though. Maybe it's not the door, but the need for an extra stairwell?

I'd hesitate to call it pretentious wank just because I don't understand it, so let's just say that the site was clearly not written for a lay audience.


You have to go digging on that site a little bit to get to the why:

"The building typology of five to six-storey apartment buildings usually involves a single shared central stair, accessed directly from the street with typically two to four dwelling units per floor. However, because the Ontario Building Code requires two means of egress, mid-rise buildings in Toronto are designed with two exit stairs connected by a common corridor. The result is that mid-rise construction only proves feasible on larger sites where around ten or more units can fit within a typical floor plan to achieve an efficient floor area ratio. Zeidler explains that “this appears to be a reasonable precaution for life safety. However, the life safety of this single stair type in Europe has been equal to, if not better than ours,” due to the fact that the single stair scheme is shared between fewer units. By changing the code requirement for two exit stairs, apartment buildings of midrise height could be designed around a single common stair. For instance, a point-access block, the dominant housing typology in dense urban contexts like Berlin, Paris, or Barcelona, is currently not permitted in Canada."

https://secondegress.ca/A-Wicked-Problem


Requiring two egresses usually means that the building will not have an apartment that spans the width of the building, instead there will be a central hallway to connect every apartment to two stairwells.

That central hallway seems small, but it eats a fairly substantial percentage of the footprint space of the building. (elevators and trashrooms are also examples of things that eat a lot of footprint; limiting them for smaller buildings is beneficial for floorplan efficiency)

And since people do not like bedrooms without windows, having apartments that don't span the width of a building limits possible floorplans, and drives the apartment design towards studios and 1 bedrooms.

The buildings tend to become very wide in order to accommodate enough apartments to make them worthwhile to build, so they tend to use up a high percentage of the lot they are sited on, which reduces greenspace and other resident amennities.


In most areas, the building code explicitly requires a window in every bedroom. This serves as an additional emergency exit, either directly on the ground floor or with assistance from firefighters on higher storeys.


Ironically, in Toronto, not every bedroom is required to have a window [1].

[1] BCC Ruling No. 14-03-1366: https://web.archive.org/web/20210422142050/http://www.mah.go...


And this shows how internationally building codes can be very different.

In Italy a room, any room for residential use, not only needs a window, but the window(s) surface must be at least 1/8 or in some cases 1/12 of the floor surface of that room, a windowless room can only be a bathroom (with a compulsory exhaust fan) or a closet/corridor/storage/utility room.

But this comes not from fire related laws, but rather from minimal health requirements (natural light, ventilation).


Which is annoying me right now as I remodel my home, because I would prefer my bedroom be a windowless cave. I would have two egresses without the window. Why must I have a third?


Stayed in a few places in Vietnam without windows and wouldn't recommend it.

As someone that will easily lie in bed to whatever hour, it's very easy to sit around in complete blackness and come outside to realise it's 4pm.


Yeah, but that isn't how my body works. The tiniest bit of light wakes me up, including headlights of cars outside sneaking past a crevice in the blackout curtains. I'm building my house for me, not for anyone else.


A big chunk of why is the % of floor area that is used for housing versus “support”. Basically a single stair layout gives you 90-95% floor efficiency, and a double stair is closer to 80-85%. People don’t rent common spaces like stairs, so you can bring the value of a building up by ~10% by allowing each apartment to have only a single exit staircase. Also if a lot is small (like 20ft wide or less), you have to compromise the design. For instance, instead of having full-floor units that get cross ventilation (windows at front and back), you may need to have duplex units that take up 40% of the front or back (so only get one side of the building).


Its the second stairwell.


Most of the buildings on the page are multistory. A door on the ground floor isn't a big deal, but above that they require fire escape stairs, which are big and ugly and create a section with poor views out the windows.


All examples seem to be about single stairs vs pair of stairs.


Which is the key issue. The second set of stairs is needed for the second egress.


This is a snarky low-effort comment. Do better.




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