C2 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. C2 districts permit a slightly wider range of uses than in C1, such as funeral homes and repair services. In mixed residential/commercial buildings, commercial uses are limited to one or two floors and must always be located below the residential use.

C2-3 is a commercial overlay district with a depth of 150 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.

C2-3 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.

R4 districts allow all types of housing at a slightly higher density than permitted in R3-2 districts. The floor area ratio (FAR) of 0.75, plus an attic allowance of up to 20% for inclusion of space under a pitched roof common to these districts, usually produces buildings with three stories.

To accommodate a potential third floor beneath a pitched roof, the perimeter wall may rise to 25 feet before being set back to the maximum building height of 35 feet. Front yards must be 10 feet deep or , if deeper, a minimum of 18 feet to provide sufficient space for on-site parking and prevent parked cars from protruding onto the sidewalk.

Detached houses must have two side yards that total at least 13 feet and each one must be at least five feet wide. Semi-detached buildings need one side yard with a minimum width of eight feet. The maximum street wall length for a building on a single zoning lot is 185 feet.

One off-street parking space is required for each dwelling unit. Height and setback requirements may be waived by authorization of the City Planning Commission.

On blocks entirely within an R4 zone, optional regulations may be used to develop infill housing when the area is already predominately built-up. A higher FAR of 1.35 is available for qualifying sites, as well as 55% lot coverage, allowing for much larger buildings with more dwelling units. Off-street parking is generally required for two-thirds of the dwelling units.