[SkeuomorphicBee]

Looking from the outside I would guess this is one of the big reasons for the "missing middle" [1] (lack of medium-density housing) in most North American cities. It is simply not economically feasible to build a small to medium size multi-unit building if you need to include two stairwells, so all buildings are either single family houses or huge mega projects.

In my country the simple and cheap four-story walk-up condo building (with a single stair and no elevator) is the bread and butter medium density housing for the working class. You either have two or four units per floor, all opening to the stairwell with almost no space lost in corridors, it is simple and efficient. Alternatively for higher density there are higher versions with typically up to 12 floors with one or two elevators but still only one stairwell, so keeping the same efficiency.

[1] https://en.wikipedia.org/wiki/Missing_middle_housing

[ajmurmann]

The two stairways result in double-loaded hallways which also negatively impact unit sizes and make it impossible to have windows on more than one wall in most rooms. It's a total disaster

[true_religion]

The fire escape can count as a separate staircase too and it can go over windows.

[Spivak]

It's crazy to me that people are arguing against two stair houses when I have a ladder in my single family home in case of a fire that blocks the stairs.

Fire in the only stairwell or a collapse, guess you just die or hope the fire department saves you before you suffocate.

[ido]

If only there was an article addressing exactly your concern!

[Spivak]

The article doesn't address this at all. There's only a passing mention of external fire escapes but no argument at all about alternative means of escaping a building in the absence of a the primary one becoming unavailable.

[ajmurmann]

The article claims that you don't need one because of the safety that comes from modern fireproofing in construction.

[sroussey]

No elevator would be a no-no here. What if you were in a wheelchair?

[amrocha]

Then find a place with an elevator. Not every home needs to be for everyone

[sroussey]

But that is not what the law says. :/

[ethagknight]

Three-story walk-ups are common and legal in America, if that is where "Here" is for you. If you are in a wheelchair, you rent a ground floor unit.

[sroussey]

Only if built before the ADA.

[quickthrowman]

The reason five over ones are popular in the US has nothing to do with staircase requirements. The reason is money, like always.

You can stick build residential buildings up to five stories and it’s way, way cheaper than reinforced concrete and steel. They are mega complexes because the financial stakeholders want to maximize the available land and rents.

[ketzo]

“maximize the available land”

Part of the author’s point is that single-stair buildings can be built economically on much smaller pieces of land. This increases the number of plots — especially in urban environments — on which you can build MFH, plots which developers today wouldn’t even think of.

Legalizing single-stair buildings would not really change the viability of big apartment complexes, you’re right. But it would allow for smaller ones.

[Pxtl]

Yes. Especially since a big problem for Western cities is not "how do I build new megalopoli" but "how do I fill in density without acquiring a whole city block of houses in one go". For a single-stair walk-up you don't need a massive amount of property, you can plonk a pretty danged nice mid-rise building on the same acreage as one large detached house.

[ajmurmann]

With a single stair you can also get windows in opposite ends of the building for the same unit which makes a huge quality of life difference. Getting a real cross-breeze!

[Tiktaalik]

> The reason five over ones are popular in the US has nothing to do with staircase requirements. The reason is money, like always.

Yes it is money. More staircases remarkably increase the costs of buildings. Single stairway, cheaper buildings, more profitable to do other sorts of buildings, more variety of buildings etc.

(see also no parking mandates)

[bluGill]

Stairs are not expensivei they take space, but are cheay otherwise

[bell-cot]

By the time you've complied with all current codes, stairs themselves do take up an unreasonable amount of floor space.

But there's a usually-worse cost to the second set of stairs, that I'll call "geometry". A second set of stairs is not a giant support column, which you can wall off and ignore. The halls, doors, and such that it requires also suck up space, and impose many more restrictions on the layout of the actual living spaces for human beings - which are the sole reason for the building to exist.

[eru]

Space ain't free.

[FinnKuhn]

In most cities space is the expensive thing

[ethagknight]

At least in larger construction, it's the pathway to the secondary stair that takes up an exorbitant amount of space, hamstrings the layout. Also, code compliant fire egress stairwells are surprisingly expensive to build, costs more than the unit cost of a living space.

[closeparen]

It’s true that five stories is an economic sweet spot, but the idea is we could get five story point access blocks instead of double loaded corridor layouts.