[kelseyfrog]

Here's a hypothetical for a two-stairwell building: two couches.

We can avoid this dangerous scenario with a three-stairwell minimum requirement.

[hammock]

Good point. Why do we even bother with two-lane roads and a double yellow line? Such a waste of space. Very contrived to presume there is always a car coming the other way

[kdmccormick]

You're comparing a situation that happens all the time (opposing traffic) with one that happens extremely rarely (blocked stairwell in a fire). If anything, you're strengthening my point.

We should design for situations to a level that is appopriate given their frequency and severity. Show me evidence that MANDATING the extra stairwell justifies the huge increase in national housing cost, and I'll concede.

[kelseyfrog]

Sorry, but the only thing that will change my mind is a significantly casualty different between single stairwell and dual-stairwell buildings accounting for building age, construction type, property value, and occupant demographics.

Happy to hear evidence-based arguments.

[sunshowers]

The US would certainly be a nicer place to live if there were more roads with just one lane, like many older cities and suburbs already have.

[matsemann]

Why would you need two lanes in each direction, except perhaps on a highway..? I agree, such a waste of space.