An accessory dwelling unit (ADU) is a residential dwelling unit that is accessory or secondary to a primary residential dwelling unit. It may be like a smaller apartment within a home, detached from the primary structure in a separate building, or constructed within an existing accessory structure (like a garage or basement).

ADUs provide new housing options that may offer relief to communities where existing residents are concerned about being priced out of their own neighborhoods.

They also help create housing options that are more economically and environmentally sustainable. The smaller building footprint also means fewer materials are used in construction, and less energy is required to heat or cool the house.

In 2018, the city enacted an ADU Overlay District for the single-family zoned portions of the Garfield neighborhood, set to expire after two years.

Since then, other cites have sought to implement policies approving the implementation of ADUs to address low housing stock and affordability.

Read more about ADUs in our subpage, linked here.

Inclusionary Zoning (IZ) ensures neighborhoods can offer new housing units at a variety of price points by tying the construction of affordable housing to that of market-rate housing.

This zoning tool requires new residential developments to make a percentage of the units affordable to low- or moderate-income residents.

IZ is used in a variety of cities across the country and is identified in the city's 2022 Housing Needs Assessment as a strategy to protect and expand access to affordable homes in the city.

An Inclusionary Housing Overlay District (IZ-O) was permanently adopted in Lawrenceville in 2021 after two years as a temporary measure. As of 2023, the overlay district includes Bloomfield, Polish Hill, Lawrenceville, and portions of Oakland.

Learn more about IZ on our subpage, linked here.

Transit-oriented development (TOD) is a policy of encouraging dense housing and amenities within walking distance of frequent and high-quality transit.

While Pittsburgh offers several TOD bonuses in the Zoning Code, these are not available city-wide. In addition, multi-unit residential buildings are only permitted on 37% of land area located within a half-mile of a transit station. Rezoning around transit stations would permit, and encourage, the creation of high-density, walkable, pedestrian-oriented mixed use development, including multi-unit residential.

Some city partners, like Pittsburgh Regional Transit (PRT), have shared research and findings about the potential opportunities for TOD. In 2016, PRT published its own Transit-Oriented Development Guidelines, and in 2021 finished a Five-Year Evaluation of TOD in Allegheny County.

Visit our TOD subpage, linked here.

The 1958 Zoning Code implemented off-street parking requirements for the first time. Most of the City was built prior to this requirement. Over the years, zoning code was amended to reduce or remove entirely off-street parking minimums in some geographical parts of the city. Many cities in recent years including Buffalo, Minneapolis, Austin, Raleigh, and others have completely removed minimum off-street parking requirements. The removal of minimum parking requirements has led to the development of more walkable, mixed-use development, lower housing costs, and adaptive reuse of existing buildings. DCP staff analyzed best practices of other cities and examined development trends in Pittsburgh regarding the amount of off-street parking provided. This work was undertaken originally at the request of Councilmember Strassburger and her staff.

Visit our Parking Reform subpage, linked here.

Minimum lot size is the smallest lot area permitted for a development in a residential zoning district. Minimum lot size per unit is the minimum lot area needed for the development of a residential unit and determines the level of density permitted. Minimum lot size requirements have historically been a tool of exclusionary zoning intended to prevent lower-income households from being able to live in certain neighborhoods.

DCP is proposing to remove minimum lot size per unit and reduce the minimum lot size requirements in all residential subdistricts.

Visit our Minimum Lot Size Reform subpage, linked here.

Anticipated in late 2025, City Planning is developing an overhaul of Pittsburgh's base residential zoning districts, in response to recommendations in the Housing Needs Assessment to remove barriers within the existing zoning code to diverse residential housing typologies.

We are looking at a framework for a modern residential zoning code oriented around the residential building types found historically in all of Pittsburgh's neighborhoods - homes, duplexes, corner stores/live-work, mid-rise, etc. - and building forms and scale that fits within the existing neighborhood character.

This is a larger scale project that will have significant public outreach, and tie to the Citywide Comprehensive Plan.