Think of an old brick building with several stories and a window per floor vs a new steel + concrete building with windows spanning multiple floors.
The "older" builder like the converted one in the parent post has small windows, allowing easy subdivisions. Newer buildings have windows spanning multiple floors and need to be retrofitted and on a skyscraper that comes at a huge cost.
The bigger ticket item is the plumbing and ventilation, and to some extent the electrical. Ventilation is needed around the cooking area and washrooms, adding that to a building not purposed for this is challenging (where does the "contaminated" air go out?).
It's often cheaper to bomb down the building and start over than doing a conversion on a new highrise. You'll see this often where they gut the entire structure and floors, keep a few walls/supporting structure, and build new.
i think the best way to describe it is to consider what an office in these types of buildings looks like.
consider a detective office in a movie from like the '50s. the office is small, primary illumination is from large, openable windows, maybe there's a front section for a secretary. that happens to be pretty more or less around the ideal size for an apartment as well, though for more bedrooms you probably need to merge adjacent offices.
now consider the office block from Office Space. it's extremely large and dark in the middle. it is so large that there is no way you could possibly get natural light into the middle easily. in Office Space that's kind of the point, the darkness and required artificial lighting makes it super depressing and a dystopian commentary on the modern economy. who would want to live in an interior like that?
Well.. yeah when you put that way I see what you mean. No those types of buildings wouldn't be very amenable, I suppose I had assumed we would already exclude those from consideration.
Note that none of the buildings I mentioned are this way (the Wikipedia links have pictures). Although.. I did live in an old saddlery building there that is somewhat like what you're saying, the hallways were just made wide and apartments very long to ensure window access. Still, an Office Space style building will never be that.
the problem now is that in 2024, these Office-Space style buildings are getting into their 40s and 50s, and with the glut of new class A office space being made available in more contemporary bright, airy open styles, that's the kind of building that is going to be a struggle to fill with new office tenants or convert to residential.
Think of an old brick building with several stories and a window per floor vs a new steel + concrete building with windows spanning multiple floors.
The "older" builder like the converted one in the parent post has small windows, allowing easy subdivisions. Newer buildings have windows spanning multiple floors and need to be retrofitted and on a skyscraper that comes at a huge cost.
The bigger ticket item is the plumbing and ventilation, and to some extent the electrical. Ventilation is needed around the cooking area and washrooms, adding that to a building not purposed for this is challenging (where does the "contaminated" air go out?).
It's often cheaper to bomb down the building and start over than doing a conversion on a new highrise. You'll see this often where they gut the entire structure and floors, keep a few walls/supporting structure, and build new.