Residential Fourth Density (R4) Zoning Review

For a more in-depth discussion of the issues facing low-rise multiple-unit development and the R4 (Residential Fourth Density) zone, please read our discussion paper [PDF 808 KB].

Once you’ve read the discussion paper, we’d like to hear what you have to say. Please send us your comments and questions by Friday, December 16:


R4 Zoning Review
c/o Tim J. Moerman
Ottawa City Hall, Mail Code 01-14
110 Laurier Avenue West, 4th floor
Ottawa, ON K1P 1J1

Fax: 613-580-2459

Email: or

Project overview

The Residential Fourth Density (R4) family of zones is the city’s most intensive low-rise residential zone. It is the only family of residential zones designed to permit low-rise apartment buildings with four or more dwelling units. R4 zoning covers much of Ottawa’s old established low-rise neighbourhoods in the inner urban area, including Centretown, Sandy Hill, Vanier, Overbrook, Hintonburg and Westboro.

Many of the rules under today’s urban residential zones are inherited from older zoning by-laws. They have not been comprehensively reviewed to assess how they are responding to current policy directions for change within established neighborhoods. This direction provides for change to be consistent with existing neighborhood character or a neighborhood’s planned function.

There is now a heightened need for such a review, especially for areas with an R4 zoning as a result of changing demographics, economics and other pressures. In some cases, the current R4 zoning is permitting development that is adversely impacting the character and planned function for some of the older more established mixed communities in the inner urban area.

The R4 Zoning Review will address those issues most commonly found in inner-urban, low-rise multi-unit development. While the focus will be on the R4-zoned areas, the review may also touch on aspects of the zoning by-law applicable to other inner urban zones, such as the R3 zones in the Glebe and Old Ottawa East. The review will specifically focus on topics that were not covered by the two recent Infill studies or the Residential Conversions study. In particular, rules governing low-rise multi-unit development will provide for such development to align with current policy directions set out in the Official Plan for stable low-rise mixed residential neighborhoods.

Key considerations for the R4 zoning review are:

  • Ensuring that new low-rise apartment buildings permitted in the R4 zones are compatible and fit with their neighbourhoods in both form and function
  • Ensuring that the R4 zones can continue to accommodate the growing number of people who want to live in the inner-urban, low-rise neighbourhoods in a way that balances the needs of new residents with those of existing residents and maintain a sense of stability
  • Allowing the R4 zones to accommodate the need for affordable housing while protecting the character of the R4 urban neighbourhoods

To address these issues, the R4 Zoning Review is expected to consider zoning tools including but limited to:

  • Differences between a rooming house and a very large dwelling unit. In recent years, there has been a trend in certain neighbourhoods for multi unit buildings being constructed (whether purpose built or through significant renovations/additions) where the individual units contain six, eight or more bedrooms. These larger units have characteristics similar to rooming houses but in the context of the zoning by-law are deemed to be dwelling units. The R4 Zoning Review will examine this and determine whether greater clarity is needed to ensure clear differentiation between a rooming house and a dwelling unit.
  • Number of bedrooms in an apartment. Part of providing for greater clarity between a rooming house and apartment may be establishing limits on bedroom counts for apartment units. The R4 Zoning Review will examine this for different residential types.
  • Number of apartment units in a low-rise building. Currently, half of the R4 subzones allow only four apartments; the other half have no limit on unit counts. The R4 review will examine the basis for this and determine if provisions should be introduced where the the number of units permitted might be tied to the size of the lot or some other criteria.

Next steps

As We Heard It

Stay tuned! We will post some of what people had to say about the R4 Zoning Review later this year.

Zoning Proposals

We expect to produce our zoning recommendations for public circulation in early 2017. Check back here for news in the New Year.

Committee and Council Dates

We plan to bring a report to Planning Committee and Council in spring of 2017. We’ll post more details as we get closer to the date.