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Residential Fourth Density (R4) Zoning Review

Project Status: 

Notice of Application of a Zoning Amendment

R4 Zoning Review: Zoning Proposals [424 KB] - March 8, 2018

In accordance with Section 34(10.7)(a) of the Planning Act and Section 3.(1) of Ontario Regulation 545/06, notice is hereby provided that a zoning by-law amendment proposal is being considered by the Planning, Infrastructure and Economic Development Department of the City of Ottawa.

Lands Subject to the Proposal 
The Zoning By-law Amendment proposal contains changes relevant to residential land uses in all zones City-wide. The proposed changes will be more substantial for development in the R3 and R4 Residential zones, and particularly the inner-urban wards (Ward 12, 13, 14, 15, 16 and 17.)

Purpose and Effect of the Proposed Amendment
The proposed amendment would:

  • introduce new definitions of previously undefined terms including "single housekeeping unit" and "bedroom;"
  • prohibit development of dwelling units with more than four bedrooms in any zone, except in the case of a detached dwelling, where an oversize dwelling unit of no more than eight bedrooms would be permitted;
  • redefine and regulate the use "rooming house" to more clearly and effectively distinguish it from the uses "dwelling unit" and "oversize dwelling unit";
  • establish minimum standards for garbage storage and management for residential buildings with total floor area exceeding 400m2 (4300 sq. ft.);
  • remove the zoning distinction between a purpose-built rooming house, converted rooming house and groups of rooming units;prohibit secondary dwelling units in any dwelling containing an oversize dwelling unit; and
  • other incidental or structural amendments to the Zoning By-law to give effect to the above intent and to improve clarity.

No transition provisions are proposed. Any development that has not received a building permit when the amendment is adopted by Council will be required to comply with the zoning as amended.

For more information, please consult the R4 Zoning Review: Zoning Proposals [424 KB]

Related Planning Applications
Not Applicable.

Further Information
For more information about this matter, including information about preserving your appeal rights, contact:

David Wise, MCIP, RPP
Program Manager
Zoning and Interpretations
110 Laurier Avenue West, 4th floor, Mail Code 01-15
Ottawa, ON  K1P 1J1
613-580-2424, ext.  13877
Fax No.: (613) 580-2459 or

Submission Requirements

The City of Ottawa would like to receive any comments concerning this proposal.Please forward comments to the above-noted planner via mail, telephone, facsimile or e-mail by April 9, 2018. Comments received will be considered in the evaluation of the proposal.

Dated at the City of Ottawa this 9th day of March 2018.

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 neighbourhoods. This direction provides for change to be consistent with existing neighbourhood character or a neighbourhood'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 neighbourhoods.

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

Committee and Council Dates

We plan to bring a report to Planning Committee and Council in the spring/summer of 2018. We'll post more details as we get closer to the date.

Project update - July 2017

Thank you for taking the time to comment on the Residential Fourth Density (R4) Zoning Review. Your comments are very important to us and will be taken into consideration as we explore ways to better manage change and new development within established inner city communities. The concerns you have expressed are shared by the City as well. We are committed to addressing them through the R4 Zoning Review and new regulations.

We are reviewing our strategy and public consultation approach. The R4 Zoning Review will be completed in two phases. The first phase will focus on an interim strategy for low-rise multiple-unit buildings. The second phase will review the broader regulatory strategy. It will explore alternatives to generally manage development activity within established inner city neighbourhoods so that change is respectively integrated with current neighborhood characteristics. The second phase will be informed by the feedback we have received from the community and community organizations. We will be hiring an external consultant to help move the project forward. 

For more information, please contact:

David Wise
Program Manager, Zoning and Interpretation
Planning, Infrastructure and Economic Development
Tel.: 613-580-2424, ext. 13877

As We Heard It - As of September 25, 2017

The As We Heard It Report includes the comments we have received since the release of Discussion Paper #2 in March. If you have not had a chance to send us your thoughts yet, please take a moment to send us an email at or

Discussion paper #2: Draft recommendations - March 2, 2017

The R4 Zoning Review has produced a set of draft recommendations, which you can access in Discussion Paper #2 [PDF 684 KB].

Once you've read the draft recommendations, we encourage all stakeholders to send us their thoughts and comments on the proposals. Please send comments no later than May 31, 2017.

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

By fax: 613-580-2459

By email: or

As We Heard It - As of November 28, 2016

Since we launched the R4 Review in September, we've received some written comments from developers, individuals and Community Associations. We have posted some of those comments below. If you haven't had a chance to send us your thoughts yet, please take a moment to send us an email at or

"Very large units with many bedrooms create what is effectively a rooming house."

We whole-heartedly support action by the City to limit the number of bedrooms permitted in low rise dwelling units such as duplexes, triplexes, and apartment buildings with four or more units. The tendency to build very large units with many bedrooms creates what is effectively a rooming house and makes a mockery of the zoning requirements. The problem of dwelling units that skirt the zoning bylaws is not limited to new construction. Numerous examples exist in our neighbourhood of semi-detached or single unit houses that are converted to multiple resident dwelling units. By signing a lease with only one resident, who in turn collects rent from the other tenants, landlords are able to circumvent the intent of regulating rooming houses. There needs to be some reasonable restriction that works in practice. (Community Association.)

"Measures in R4 may simply move the problem to adjacent zones."

We are concerned that action to limit the number of bedrooms only in the R4 zones will simply transfer the pressure to build what may be termed ersatz rooming houses to the R3 zone, where triplexes are permitted. Already there are examples in our neighbourhood of triplexes which are effectively 12 to 15 unit rooming houses. We feel that there needs to be regulation of both R4 and R3. (Community Association.)

"Demand for student housing is not sustainable; what happens when these units are no longer needed?"

The numbers of students attending university and college is now starting to decrease due to demographic change. This means the demand for the low grade housing is starting to ease. This housing is not amenable to other uses or potential residents, and thus may end up being abandoned or left in a state of even further disrepair. Action needs to be taken now to prevent this problem from occurring in the next few years. (Community Association.)

"Lack of parking"

The intensification of usage of both existing dwellings and new construction has led to a lack of available parking. Although the intention of intensifying development is for the tenants or owners to rely on public transit, they often do own cars, even university students. These vehicles are frequently parked on the streets, or the owners convert required green space on their properties into parking. With so many cars parked on the street it is sometimes difficult for vehicles to pass each other, particularly for large emergency vehicles, and especially in the winter. We can petition to reduce the parking to only one side of the street, but with a large proportion of the housing stock rented it is very difficult to achieve the necessary level of acceptance to do this. There need to be changes to the rules of intensification, either making it easier to restrict parking to one side of the street, require more on-site parking, or both, to ameliorate this problem. (Community Association.)

"Loss of communal green space"

Intensification reduces the amount of communal green space available. Firmer rules around the provision of parks and green space where intensification of usage is permitted are required. (Community Association.)

"Limits on bedroom counts cannot be effectively enforced."

It is difficult to see how limits on bedroom counts per unit would work; how are you going to prevent someone from bedding down in a “family room” or so-called “den”? For similar reasons, refining definitions of “rooming houses” and “apartment buildings,” or that tying number of units to lot size, are problematic. (Individual.)

"Oversized dwelling units are cost-effective given a limit on permitted units."

A large dwelling unit is the only way for development to be cost effective for the builder, and ultimately the for renter where the number of units is limited to 4 unit in R4 zone (such as Sandy Hill). If the City granted higher unit density, these large dwelling units would immediately disappear for a more traditional unit size. (Developer.)

"Residential licensing"

Another point is to allow this type of dwelling, but enforce landlord licensing. This way, from a city bylaw/permit point of view it's fine, and from a community point of view it's also taken care of with the licensing. (Developer.)

"Permit oversized dwelling units, but only in detached buildings"

We support the proposal to define an “oversized dwelling unit” as one in the six-to-eight range of bedrooms; to disallow more than eight (or even more than six); and to limit ODU’s, as defined, to detached dwellings. And by all means, let’s distinguish oversized dwelling units and rooming houses in Ottawa’s zoning by-law definitions, this in line with court and OMB rulings. (Community Association.)

"Cautiously support reviewing four-unit limit in the junior R4 (R4A-R4L) subzones"

We are concerned that the proposal to raise the current four-unit limit in the junior R4's might encourage developers to max’ out building envelopes, giving them more diverse ways of doing so. However, maxed-out envelopes which also contain ODU’s, resulting in maximum densities, are the most objectionable forms of infill. On that account, we are inclined to support this proposal, assuming that its effects would be monitored and, if called for, reconsidered at a predetermined time. (Community Association.)

"Support limiting bedroom counts in dwelling units, but caution against being too restrictive"

We do feel that the Discussion Paper suggestion of a maximum of 50% of units having more two bedrooms is too restrictive. It would have the effect that, in duplexes and triplexes, only one unit can contain more than two bedrooms, which would be an excessive restriction. We would not want to prohibit a building devoted entirely to housing families - with every unit containing e.g. three bedrooms.

The idea of restricting bedroom counts is a good one. We don’t like complicated regulations but a more refined formula might be called for. For example, a relatively simple provision,  such as, only 30% of units can be more than three bedrooms – would be more acceptable to all. This would be restrictive but still control the extraordinary cases of 6, 8 or 12 bedroom units to that of being a smaller portion of the space within those multi-unit residential buildings. (Community Association.)

"Unsure/conflicted about reviewing the minimum lot size for low-rise apartment dwellings"

You give a good account of “unintended consequences”, whereby restricting a lot to a duplex or three-unit dwelling on the basis of its size, simply encourages the same massing and occupancy across fewer units. It highlights the difficulty of devising rules (by-laws, as distinct from mere guidelines) that will produce more appropriate infill while we continue to intensify.

Allowing apartment dwellings on smaller lots than the zoning currently allows may mitigate this identified unintended consequence. On the other hand, it may result in more, skinnier (and probably boxy) 4-storey apartment buildings, infilled in some established streetscapes characterized by attractive, more traditional, peaked and considerably lower building forms. (Community Association.)

"Requiring indoor garbage storage for all multiple-unit housing forms is excessive where development is already subject to site plan control."

We do not support the proposed provision to require indoor garbage storage for all multiple unit housing forms. If there are problems of garbage storage with dwellings such as duplexes and triplexes that are not subject to site plan control, then making indoor garbage storage a requirement under the zoning by-law does make sense. However, for those multiple residential units already subject to site plan control that planning mechanism is sufficient to regulate where and whether the garage storage area need be in a building or in a fenced exterior location. (Community Association.)

"Interested in hearing more about maximum lot sizes for low-rise apartment dwellings."

We strongly agree about the need for further consideration to recognize and address the potential problems presented by lot consolidation and the massively out-of-scale development that can follow. We would like to hear some proposals before the R4 Zone Review comment period closes and while there is still time for discussion. Lot consolidation in the middle of a block of uniformly sized lots to permit a larger sized multi-unit dwelling would not be appropriate. But on a street with many lots of quite variable sizes or at the end of a block or on collector roadways they might be appropriate. Lacking a CDP or secondary plan for our area is there some way in which lot consolidation policy direction can be provided? The Official Plan is meant to be a general high level guiding document. Can it get into such detail or is that best left to a supporting document approved by council, even if only a “guideline” document? (Community Association.)

"What safeguards can ensure that a neighbourhood's evolution is indeed gradual and that new development is in fact compatible?"

There are some streets already displaying a wide mix of heights, including sites with old and undersized houses, some in less than top shape, that are ripe for redevelopment,  where higher and denser would be quite appropriate. However, a large part of our established and very predominantly low-profile community is zoned R4 (and R3). The great majority of streets and blocks in these zones have “desirable characteristics” and attractive streetscapes that are presently vulnerable and exposed to ill-fitting 4-storey apartment building infill (and 11-metre high, flat-roofed triplexes).The Discussion Paper suggests that apartment buildings could be permitted on smaller lots than currently allowed, “...subject to zoning and other rules that ensure that this will be physically compatible with the neighbourhood.” It’s that last clause that’s the catch. Such “zoning [regulations] and other rules” don’t presently exist. The manner in which Sections 2 and 4 of the Official Plan address compatibility and mitigating measures is in need of much improvement. It affirms that ‘compatibility is not quantifiable,’ and then sets out a list of “measures” that can be used to mitigate non-compatibility. The abuse occurs when planners ‘add up’ a number of mitigating measures employed by a developer and conclude that the ‘total’ renders the development “compatible.” The result is, frequently, that a proposal that is patently incompatible is deemed to be okay (compatible) by City’s professional planners with supporting arguments quoting lines or “measures” from the Official Plan which ordinary people can in no way refute. (Community Association.)

"Agree that development charges should be reviewed at the next opportunity; currently they incentivize a smaller number of very large units."

You indicate that there is only one DC fee for apartments notwithstanding their size or number of bedrooms. So in the case of four very large units the charge would be payment of four DC fees, yet the same sized building split into 16 units would be required to pay 16 DC fees. It appears that the incentive is to have bigger units with more bedrooms because you pay less DC fees. This does not respect the intent of development charges that are to be “roughly proportional to their occupancy”. We understand that having a two charge rate depending on size for apartments might discourage their construction if the cut off between the two types is set too low, e.g. at two or three bedrooms. If however it is set higher say at six bedrooms this is justifiable, which may discourage the creation of those units with 8, 10 or 12 bedrooms. However, as with the zoning provisions limiting bedroom counts, we wonder if there would be attempts to get around this by labelling bedrooms as “studies” or “dens”?  (Community Association.)

"Concerned about student rooming houses"

I'm writing to voice my concerns with yet another "rooming house" being built in my neighbourhood.  I moved to this area because of its charm and quiet established atmosphere.  Since moving into the area it has quickly become what feels like an extension of Ottawa University's frat housing.  I guess there isn't enough student housing on campus. Don't get me wrong, I don't mind students renting rooms in the existing homes, but building all these rooming houses without consideration to the residents needs is not fair.  Already there is garbage littered on their lawns and at times not being picked up (by the city).  There is barely enough parking on the street as it is.  My visitors are finding it more and more difficult to find a spot in the area and when winter comes this is worse. (Individual resident.)

Discussion paper #1 - November 2016

In November 2016 we posted a discussion of the issues facing low-rise multiple-unit development and the R4 (Residential Fourth Density) zone. Please read our first discussion paper [PDF 808 KB].