Yeah, this tweet-complaint list is simply not true. SRO/Tenements are obviously not legal (for good reasons, imho). But the other examples in the tweet thread are legal in most cities, and these get built all across the US literally every single day.

In my small-ish Michigan city alone, we have multiple examples of #1, #3, #4, #5, #7, and #8, all of which have been built this decade. The same is true in Minneapolis, and Portland, and Seattle, and Chicago, and others.

I think you are missing the point if you think the author implies that they are completely banned. They are obviously not all banned. The issue is that they are banned in certain places. Most cities strictly regulate where you can build different things and have restrictions on setbacks and parking for all of those things. In my midwestern town, I could not tear my house down and build an apartment. It is zoned for 'single family 2nd density residential.'

A lot of them are common in places where they were built before modern American zoning laws came into being.

#5 is common in new construction today, in the NIMBY-heavy Northern California (including the SF Bay Area), which is, to be sure, not free of the influence of “modern American zoning laws”, and I can think of at least one Bay Area small town where (if one restricts to residential structures) the same developments that contradict #5 also is do so for #8. The essential equivalent of #7 is a common form (including, again, in the Bay Area) of newer condo development, though they are usually marketed as “townhouses” rather than “rowhouses”.

For every one place you see it built, there's many more places zoned in such a way to exclude it. You're seeing the few exceptions.

> For every one place you see it built, there's many more places zoned in such a way to exclude it.

I've seen it in virtually every urban and suburban area of Northern California, it's practically the on-trend mode of infill development and has been for a couple decades. Either Northern California has the reverse relationship to the rest of the nation that it is reputed to have for development (which I doubt), or the assertion that this is prohibited in most US cities is false.

You don't know what was required to get it approved. It might be allowed only in certain areas of town by right. I can't even convert my detached garage into a living space where I live.

> You don't know what was required to get it approved. It might be allowed only in certain areas of town by right I know that it wasn't prohibited I. The cities in which it was approved and built; the claim was that it was prohibited in most cities, not that it required special permits in most cities outside of limited predesignated areas.

I'm simply not going to treat a Twitter thread making claims about what is prohibited in development in most American cities that provides no evidence of this widespread prohibition seriously when several of the things it points to are clearly not prohibited in most cities in the region notorious for being unusually restrictive about what is allowed in development.

Now, sure, that's not disproof of the claim, not have I claimed that it is. But it is more than a sufficient to demand evidence before granting it credence, and when even those trying to defend the claim have to shift the goalposts far from the actual claim, I think that's a further indicator of it's shaky ground.