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.
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.
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.
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...
Try your Stockholm apartment in that.
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?
I’m pretty sure sprinklers have been shown to massively increase fire safety.
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.