Is this the kind of thing you're looking for? Krisana Park is a mid-century neighborhood in Denver. I had the opportunity to tour the neighborhood last year during the Saving Places conference.
I don't know how effective it's been, how hard it was to pass or any of that info. From what I remember, property owners can still add additions (but only in the rear and only up to a certain height) and they can still demolish their properties. But the height limits and design guidelines remained in place for new construction, which they hoped would be enough to discourage demos.
I'm eager to hear of more examples. We've been wondering about seeking conservation overlays in Fort Collins as well.
Here in Venice, Florida we have historic districts, but we also have several architectural districts and overlays. The historic districts fall under the purview of historic preservation board, but the others to the architectural review board. These other districts and overlays have overriding statutes to have areas comply to a certain look or design.
Historical Resources Manager
City of Venice
Venice Museum & Archives
Yes, that's how I think of it, too -- preservation lite.
If you'd like a version of conservation that's ultra lite, you could check out what Fort Collins has. The pre-WWII neighborhoods have been zoned as Neighborhood Conservation Medium density (NCM) and Neighborhood Conservation Low density (NCL) and there are some requirements for articulation, front porches, solar access and FAR as a percentage of lot size. This has also come with design guidelines for compatible development (which are completely optional). But these "restrictions" are very generous and allow for buildings easily 3 or 4 times larger than the historic structures. Most preservationists in town see all of this more as band-aid measures than anything effective. If you're interested in learning more, here are some links. Old Town Neighborhoods Plan and Old Town Neighborhoods Design Guidelines can be found here: Old Town Neighborhoods Plan || City of Fort Collins
The ordinance that addresses articulation, solar access, and front porches: https://www.fcgov.com/planning/pdf/ord-0332013.pdfI also attached two photos. The green house is what we were up against and trying to stop. (The new house is 7 times the size of the older house that's next to it.) The house between two others is what's allowed under the new (ultra lite) rules. (Not a whole ton better.)
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