Ottawa N4 Zoning Rules - Multi-Unit Buildings

The N4 zone is Ottawa's highest-density residential neighbourhood zone under Zoning By-law 2026-50. Located primarily along transit corridors, near mainstreets, and in inner-urban areas, N4 properties have the greatest development flexibility in the N zone family. If your property is zoned N4, you may be able to build a larger multi-unit residential building than you'd expect — and potentially without any limit on the number of units.

What is the N4 Zone?

The N4 — Neighbourhood High zone is the top tier of Ottawa's residential neighbourhood zoning under By-law 2026-50. It replaced most R4 zones from the old 2008 by-law, though some former R4 subzones with lower density limits were reclassified as N3 during the revision process. N4 zones are concentrated in the inner city, along LRT corridors, near mainstreets, and in areas identified by the Official Plan for intensification.

For comparison with lower-density zones, see our guides on Ottawa N3 zoning rules and the broader overview of Ottawa's new zoning by-laws.

What Can You Build in N4?

The N4 zone is designed for apartment-form and mixed-use residential development. Permitted uses include:

• Apartment buildings — mid-rise and potentially higher near transit
• Multiplexes — no unit cap in standard N4
• Stacked townhouses
• Mixed-use buildings — residential above ground-floor commercial on appropriate streets
• Live-work units — small-scale commercial or home office use integrated into residential
• Secondary suites and ADUs

The standard N4 zone has no maximum unit count — the only limits come from height, lot coverage, setbacks, and parking. This makes N4 Ottawa's most investment-friendly residential zone for multi-unit development. For investors exploring Ottawa's high-density zones, see our guide on how many units you can build on a typical Ottawa lot.

Height Limits in N4

The baseline maximum building height in N4 is 14.5 metres (approximately four storeys). However, this is a floor rather than a ceiling in many N4 locations:

• In N4 subzones near LRT stations and bus rapid transit corridors, additional height permissions may apply
• Properties at the intersection of N4 and Mixed-Use or Hub zones may be subject to different height frameworks
• Height transitions apply where N4 properties abut lower-density N1–N3 zones, governed by angular plane rules

The City of Ottawa's zoning review resources and GeoOttawa mapping tool are the best starting points to check height permissions for your specific N4 subzone.

Parking Requirements in N4

One of the most significant changes under By-law 2026-50 for N4 properties is the reduction or elimination of minimum parking requirements near transit. In transit-supportive N4 zones, no minimum parking spaces are required — substantially reducing construction costs and enabling more units on the same lot footprint. This change is intended to encourage transit use and lower the cost of new housing in well-serviced locations.

Mixed-Use and Ground-Floor Commercial

By-law 2026-50 introduced permissions for limited commercial uses in some N4 zones, enabling small-scale live-work arrangements and neighbourhood commercial uses at ground floor levels on appropriate streets. This opens possibilities for mixed-income, mixed-use buildings that support walkable neighbourhoods.

N4 and the City's Official Plan

N4 zones are tightly aligned with Ottawa's 2022 Official Plan, which directs intensification to designated growth areas — particularly near transit stations and along mainstreets. If your N4 property falls within a Mainstreet or Hub designation, additional permissions and review processes may apply. The Engage Ottawa zoning portal shows how your property's zoning interacts with Official Plan designations.

From R4 to N4: What Changed?

For property owners who held R4-zoned land before By-law 2026-50, most R4 zones became N4, but some R4 subzones with specific unit density limits were reclassified as N3 instead. Our article on Draft 2 of the 2026 zoning by-law changes explains the R4-to-N3/N4 conversion process in detail.

The Development Process for N4 Projects

Multi-unit apartment projects in N4 zones involve a more detailed planning and permit process than smaller residential projects. You will typically need:

1. A confirmed zoning analysis for your specific N4 subzone
2. An architect to prepare a full set of design drawings
3. Pre-consultation with City planning staff (required for larger applications)
4. A site plan approval application for projects above a certain size threshold
5. A building permit application complying with the Ontario Building Code and By-law 2026-50

For context on the overall building permit process, see our guide on building permits for new construction in Ottawa. Also see our article on converting an Ottawa home into a multiplex for strategy context.

Considering a Multi-Unit Development in N4?

Ottawa General Contractors works with landowners and investors on multi-unit residential projects across Ottawa's N4 zones. From initial zoning review and design to permit submission and construction management, we provide end-to-end support for high-density residential development. Contact us today to discuss your N4 development project.