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Apr 06

[ARCHIVED] Nonconformities

The original item was published from April 6, 2018 1:13 PM to April 6, 2018 1:25 PM


A nonconformity is an existing lot, structure, or use that does not comply with existing zoning standards for such things as size, location, use, or height.

 type examples
  • building is in the setback
  • building is too tall
  • building exceeds lot coverage limit
  • lot is smaller than district standard
  • frontage along right-of-way is inadequate
  • dimensions are inadequate (width,depth)
  • retail store in residential district
  • house in industrial district
  • parking, landscaping, or signs are non-standard


Legal nonconformities are lots, structures, or uses that either predate zoning or conformed to the zoning standards in effect at the time of their establishment.

Illegal nonconformities did not comply when they were established. Whether done inadvertently or not, an illegal nonconforming structure is one that was built too tall, too big, or too close to a lot line or another building. A illegal nonconforming use is an activity that was started in violation of laws in effect at the time, such as a business in a zoning district that did not allow commercial uses.

 type examples
  • setback standard later increased
  • minimum lot size later increased
  • density was later reduced
  • zoning district or rules were later changed
  •  was built encroaching on then-current setbacks
  • non-conforming use was establish


Not all nonconformities need to go away. Some are benign and unremarkable—it’s doubtful that anyone notices or is worried that most houses in the Wards are closer to the sidewalks than they are in postwar suburbs. Some may even be over the 35-foot height limit. Guess what? Despite these violations the world keeps chugging along.

Because of this, the trend in planning over the past couple of decades has been to erase the label “nonconformity” for these benign nonconformities by making them conforming. Cities are changing their zoning laws, often—as here in Manhattan—by applying a special overlay zone that allows closer setbacks or some different uses. When cities do this homeowners can make improvements to their houses without having to jump through unnecessary hoops (i.e., Board of Zoning Appeals applications).

On the other side of this are nonconformities that are undesirable because they are incompatible with their surrounding uses or structures, or because they pose some kind of hazard or nuisance. These are the kind that cities try to phase out over time, typically by limiting expansions of the use or structure, or preventing rebuilding or reoccupancy. In more extreme cases a city might undertake nuisance abatement, schedules of amortization that require conformance within a set period, or public buyout for willing sellers.

 type benign undesirable
  • setback
  • height
  • coverage
  •  encroaching on public right-of-way
  •  smaller than dist. std.
  •  no frontage
  • corner store in a housing area
  • parking inadequate
  •  offensive use in an incompatible zone
  • parking is VERY inadequate


As part of the Unified Development Ordinance project, the consultant, staff, and the steering committee are re-examining the City’s approach to nonconformities. For benign nonconformities we are looking to remove the nonconforming label by changing the rules for setbacks or building coverage. The more difficult discussion will center on the less desirable nonconformities: What’s the community’s level of tolerance for some of these nonconformities? Which ones should the City try to mitigate in the public interest? What mechanisms can the City use? These are all difficult questions for any city to wrestle, so stay tuned to the public meetings schedules—it should be interesting.