Multifamily zoning approvals in Philadelphia

Philadelphia zones multifamily into the RM, Residential Multi-Family districts of Title 14. A project that meets every standard of its district moves to a zoning permit; a larger project adds Civic Design Review, and a project that cannot meet a standard goes to the Zoning Board of Adjustment.

The RM districts

The city's Zoning Quick Guide (February 2026) lists multi-family as "permitted as of right" in RM-1 through RM-4. RM-1 sets a 38 ft height, a 1,440 sq ft minimum lot and a density of one unit per 360 sq ft of lot area for the first 1,440 sq ft, then one per 480 sq ft beyond it. RM-2, RM-3 and RM-4 set a floor area ratio instead of a flat height limit: 70 percent of lot area, 150 percent and 350 percent (Section 14-701).

The Mixed Income Housing Bonus

Section 14-702(7) lets a developer set aside 10 percent of new units for low income (50 percent AMI) or moderate income (60 percent AMI) households, or pay into the Housing Trust Fund, for a zoning bonus. The bonus is set per district: in RM-1 it is a 25 percent increase in units at the moderate level or 50 percent at the low level; in RM-2, RM-3 and RM-4 it adds to the floor area ratio, from 25 percent in RM-2 to 175 percent in RM-4 at the low level (2025 Mixed Income Housing Program Report). Section 14-533, the Mixed Income Neighborhoods Overlay, instead requires 20 percent of units at 40 percent AMI in a mapped area, for a development of 10 or more units.

Civic Design Review

Civic Design Review is an advisory review by the Philadelphia City Planning Commission, with a committee of community, design and development members appointed by the Mayor. It is triggered by new construction or an addition of more than 100,000 sq ft or 100 dwelling units citywide, or more than 50,000 sq ft or 50 dwelling units within 300 ft of a residential district. The committee's recommendations are advisory; the applicant chooses whether to apply them.

The Zoning Board of Adjustment

A project that cannot meet a standard of its district appeals a Notice of Refusal to the Zoning Board of Adjustment for a variance. Under Section 14-303(7)(e) and (8)(e), the appellant shows one or more unique physical conditions at the property that make the standard impossible to meet, that the variance requested is the smallest necessary, and that it will not unduly affect nearby properties.

Questions

Is multifamily a permitted use in Philadelphia's RM districts?

Yes. The city's Zoning Quick Guide lists multi-family as "permitted as of right" in RM-1 through RM-4, each with its own height or floor area ratio limit (Title 14, Section 14-701).

What does a project receive under the Mixed Income Housing Bonus?

A 10 percent affordable set-aside, or a payment to the Housing Trust Fund, earns a bonus set per district: added units in RM-1, and added floor area ratio of 25 to 175 percent in RM-2 through RM-4 (Section 14-702(7)).

What triggers Civic Design Review in Philadelphia?

New construction or an addition of more than 100,000 sq ft or 100 units anywhere in the city, or more than 50,000 sq ft or 50 units within 300 ft of a residential district.

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