Ottawa's new Comprehensive Zoning By-law replaces the legacy R1 designation with a new N1 (Neighbourhood 1) zone covering the city's lowest-density residential neighbourhoods. If your property falls in N1, the rules around what you can build — detached homes, secondary dwelling units, coach houses, additions — have changed. This 2026 guide breaks down the N1 permissions, lot and setback requirements, height limits, and the most common N1 build scenarios Ottawa homeowners are asking about.
N1 is the new "Neighbourhood 1" zone replacing most of the old R1 designation under Ottawa's Comprehensive Zoning By-law update. It covers established low-density residential neighbourhoods — think much of Alta Vista, parts of Kanata, mature areas of Nepean, and Glebe edges — where the prevailing pattern is detached single-family homes on larger lots. N1 is the most restrictive of the new N1–N4 family. Critically, even N1 now permits up to four residential units per lot as-of-right under provinc...
As-of-right permitted uses on an N1 lot in 2026 include: detached dwelling (principal), duplex (two units in the principal building under Bill 23), secondary dwelling unit (e.g., basement apartment), coach house / detached secondary dwelling, garden suite (where servicing permits), home-based business (subject to home-occupation rules), bed and breakfast (limited rooms), group home (small), and accessory structures (sheds, garages, pergolas). What is NOT permitted as-of-right on N1: multiplexes ...
Minimum lot area for the principal detached dwelling on N1: typically 360–450 m² depending on subzone (urban N1A vs suburban N1B vs rural-fringe N1C). Minimum lot frontage: 11–15 metres. Front yard setback: 4.5–6.0 m (or matching established setback on the street). Rear yard setback: 7.5 m minimum (reduced where coach house permitted). Interior side yard: 1.2 m minimum each side (1.5 m if 2.5+ storeys). Maximum lot coverage: 40–45% for principal building, with additional 15% for accessory struct...
Maximum building height: 8.5–11 metres depending on subzone, typically permitting 2–2.5 storeys. Maximum storeys: 2.5 in most N1 areas, 3 in some N1A subzones with conforming-design provisions. Coach house maximum height: 6.1 m and 1 storey (or 2 storeys if proportioned to lot — check subzone). Roof projections (chimneys, vents, gables) are allowed above the height limit per standard exclusions. If you want a taller home or third storey beyond what your N1 subzone allows, you need a minor varian...
Under Bill 23, every Ontario residential lot — including N1 — permits up to 4 dwelling units provided servicing and lot configuration work. The most common N1 build-out paths: (1) Single detached + basement secondary suite = 2 units. (2) Single detached + basement suite + coach house = 3 units. (3) Single detached converted to duplex + basement suite + coach house = 4 units. Each additional unit requires its own building permit, may trigger water/sewer upgrade fees, requires separate egress and ...
Typical reasons N1 builds need a Committee of Adjustment variance: (1) Reduced rear yard for coach house under 7.5 m. (2) Increased height above 8.5/11 m. (3) Reduced front-yard setback to match an addition. (4) Increased lot coverage above 45%. (5) Reduced parking — N1 typically requires 1 parking space per dwelling unit, with some inner-urban exemptions. (6) Heritage-overlay restrictions on demolition, exterior cladding, window proportions. A minor variance application costs ~$1,650 (2026) and...
R1 was replaced by N1 (Neighbourhood 1) under Ottawa's new Comprehensive Zoning By-law. N1 retains the low-density character of R1 but now permits up to 4 residential units per lot as-of-right under provincial Bill 23, where the old R1 was generally single-detached only.
Up to 4 dwelling units per lot under Bill 23, provided lot configuration and water/sewer servicing capacity allow. Common combinations: single detached + basement suite + coach house = 3 units; or duplex + basement suite + coach house = 4 units. Each unit needs its own building permit.
Typically 8.5–11 metres and 2.5 storeys depending on N1 subzone (N1A urban, N1B suburban, N1C rural-fringe). Coach houses are limited to 6.1 m and 1 storey in most subzones. Heights above the limit require a minor variance from the Committee of Adjustment.
Not always. If your lot meets minimum rear yard (7.5 m), coverage (≤45% principal + 15% accessory), and parking provisions, a coach house is permitted as-of-right. Variances are needed when you can't meet one or more setback, height, or coverage rules — about 35–50% of N1 coach-house projects require one.
Use GeoOttawa (maps.ottawa.ca) — search your civic address, then enable the Zoning layer. Your designation will display as N1A, N1B, N1C, N2, N3, N4, or other. For interpretation help, request a Zoning Confirmation Letter from the City for $193 (2026 fee) — useful before any property purchase.