Pittsburgh Zoning Districts - RM Overview

By Carolyn Ristau

Introduction

Zoning districts are a fundamental building block of zoning regulations and set the base use, height, and density standards. The RM or Multi-Unit Residential is one of five R or residential zoning districts in Pittsburgh. Just over 3 square miles or 6.35% of the city falls into an RM zoning district. In this post, we provide an overview of the challenges when working on a site in the RM zone. Additional posts will dive into the uses and density regulations for the RM.

Note: There are additional “special” zoning districts that are also predominantly residential, but they are grouped separately from the “R” residential districts.

Refer to our Introduction to Pittsburgh’s Zoning Districts for the complete list of base zoning districts in the city. Pittsburgh’s interactive zoning map can be used to verify the project site’s zoning district and density subdistrict.

Challenges

While multi-unit developments are permitted in the RM zoning district, these projects require large lots to meet the setback and minimum lots size per unit requirements. Interior side setbacks are at least 10 ft while front, rear, and exterior side setbacks are 25 ft or 30 ft depending on the density subdistrict. In the very low density subdistrict, the minimum lot size per unit is 8,000 sq ft. In contrast, the minimum lot size per unit in the very high density subdistrict is 400 sq ft. The lower densities present the recurring problem seen in the R2 and R3 that the minimum lot size per unit often does not match the existing lot size conditions of the city.

The same setbacks apply to single-family dwellings, duplexes, and triplexes as to a multi-unit project. With the typical lot sizes of the city, it is often hard to fit a house on a lot with a 5 ft side setback. In the RM, this setback is doubled. Unless the RM lot is larger than average, a bandage or Zoning Board variance will be required to fit even a single-family dwelling.

Zoning’s Morality

Pittsburgh’s zoning code (and many others) is intended “to promote the health, safety, morals and general welfare of the community” (901.03, emphasis added). The primary moral that zoning promotes is the “sacred” single-family dwelling (with a male head of household, housewife, and children). In the decision of the Supreme Court case that legalized zoning by use, apartments were referred to as parasites that pollute the single-family dwelling (Euclid v. Ambler).

Pittsburgh’s RM zoning district illustrates the pervasiveness of the moral judgements put on people based on their housing type. While it is the most permissive of the city’s residential zoning districts and even permits the “parasitic” apartment building, there are other housing types that require extensive hearings with public comment (which often includes sentiments such as “we don’t want those people in our neighborhood”). There are also three zoning-designated residential uses that are deemed as incompatible even with the “parasites:” dormitories, fraternities/sororities, and multi-suite residential (aka today’s co-living or the past’s boarding house).

In the question of is housing a human right, zoning declares not.

Conclusion

The zoning district sets the base use, height, and density standards for any project. The RM continues the challenge of minimum lot size requirements that may not match the existing conditions, which also comes up in the other residential zoning districts. The setbacks also present challenges for fitting buildings on average lots. While the zoning district sets the base standards, there may be “bandages” that can provide some relief, or a project may request variances to these requirements.

Also, keep in mind that meeting these base standards does not guarantee zoning approval as there may be additional zoning regulations that apply - the most common are parking and environmental requirements.

The RM also illustrates that zoning has a clear hierarchy of housing types with the single-family dwelling at the top as the most moral type of housing, apartments as not moral living, and dorms and co-living as really not moral.