Zoning Terms Defined

Decoding zoning takes more than just a map - it takes a glossary too!

Terms are defined in accordance with the National Zoning Atlas How-To Guide. Learn more about the NZA How-To Guide here.

Permission to build a specific use that is allowed without a public hearing. Building a specific use is only subject to review of staff to ensure compliance with zoning and not subject to a public hearing.

  • May also be referred to as "permitted" or "allowed."

Permission to build a specific use that is allowed only after a public hearing/review process, allowing for public comment and input and involves more discretion in decision-making than a by right use process.

  • Commonly referred to as "special permit."

Explicitly prohibits a specific use.

A district that allows for housing only. Customary accessory uses may also be allowed in primary residential districts such as religious institutions, schools, and agricultural uses.

  • Primary Residential districts typically begin with "R-", "A-", or "AR-."

A district that allows for both housing and nonresidential uses. Housing may be located in the same building as a nonresidential use (such as a business on the first floor and apartments above) or may allow for housing in a separate structure.

  • Example: Mixed Use District, Village District, Neighborhood Business District.

A district that prohibits residential uses entirely or allows for one accessory dwelling on the same lot as a nonresidential use (such as a caretaker apartment).

  • Example: Industrial District, Open Space District.

A planned development that allows for a large number of housing units to be developed in accordance with a coordinated master plan, offering flexibility with respect to grouping, placement, size, and use of structures.

  • Example: Cluster development, Planned Unit Development (PUD), Planned District (PD).

A single unit of housing located on the same lot as, and is accessory to, the principal use/structure. May be attached (in a basement, attic, or an attached addition) or detached (a standalone housing unit or within an existing detached accessory use such as a garage).

  • Also commonly known as an accessory apartment, in-law, carriage house, and granny flat, among others.

The minimum size of a parcel of land to be developed for a particular use. Minimum lot sizes often change based on the type of housing proposed.

  • Expressed in acres in the Zoning Atlas, but municipalities may express the requirement in acres, square feet, or a combination of both.

The maximum number of units allowed per acre.

The minimum number of feet that a building must be from the front lot line.

The minimum number of feet that a building must be from the side lot line.

The minimum number of feet that a building must be from the rear lot line.

The maximum amount of a lot that may be covered by buildings and/or impervious surfaces expressed as a percentage of the entire lot area.

  • May be calculated as Maximum Building Lot Coverage (coverage of the building alone), Maximum Impervious Lot Coverage (building and other impervious surfaces combined), or both.

Zoning typically requires a set number of parking spaces per housing unit or housing type. Some parking requirements may be based on the number of bedrooms in a unit (more common for multifamily housing).

The maximum number of stories that a building may be.

The maximum height (expressed in feet) that a building may be.

A cap on building size that is expressed as a ratio of the total gross building floor area to the area of the lot.

  • Example: a 0.5 FAR would enable a person to build a house with 2,000 sq. ft. of gross floor area on a 4,000 sq. ft. lot.
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Providence, RI 02903

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