C1 districts are mapped as commercial overlays within residence districts. They are mapped along streets that serve the local retail needs of the surrounding residential neighborhood.

Typical retail uses include grocery stores, restaurants and beauty parlors, catering to the immediate neighborhood. C1 districts are more restrictive than C2. In mixed residential/commercial buildings, commercial uses are limited to one or two floors and must always be located below the residential use.

C1-4 is a commercial overlay district with a depth of 100 feet. These districts are largely found in throughout the city's lower and medium-density districts.

Overlay districts are distinct from other commercial districts in that residential bulk is governed by the residence district within which the overlay is mapped. All other commercial districts that permit residential use are assigned a specific residential district equivalent.

When residences are constructed in any commercial district, certain regulations that apply in residence districts are waived, such as front and side yard requirements.

C1-4 overlays mapped in R1 through R5 districts have a maximum commercial FAR of 1.0. When mapped in R6 through R10 districts, however, the maximum commercial FAR is 2.0.

Commercial parking requirements are highly complex, reflecting traffic-generating qualities of the various commercial uses, their size and proximity to mass transit. Generally, the lower the numerical suffix, the more off-street parking is required in a particular district.

The Quality Housing bulk regulations which are mandatory in R7A districts, typically produce high lot coverage, seven- and eight-story apartment buildings, blending with existing buildings in many established neighborhoods. R7A districts are mapped along Woodhaven Boulevard in Queens and Ocean Parkway in Brooklyn.

The floor area ratio (FAR) in R7A districts is 4.0. Above a base height of 40 to 65 feet, the building must set back to a depth of 10 feet on a wide street and 15 feet on a narrow street before rising to its maximum height of 80 feet. In order to preserve the traditional streetscape, the street wall of a new building can be no closer to the street line, up to a depth of 15 feet, than any building within 150 feet on the same block. The area between a building's street wall and the street line must be landscaped.

Off-street parking is not allowed in front of a building. Parking is required for 50% of dwelling units and may be waived if 15 or fewer spaces are required.