Can i put a garden suite on my lot in Moncton if i already have a basement apartment — is two units allowed?

In Moncton, having a basement apartment already in place doesn't automatically block you from adding a garden suite — but whether two accessory units are permitted depends heavily on your specific zoning designation and lot characteristics.

Moncton's zoning bylaw has been evolving, and the city has been generally supportive of gentle densification. Most residential zones in Moncton permit at least one secondary suite (like your basement apartment), but stacking a garden suite on top of that — giving you a total of three units on one lot (main house + basement apartment + garden suite) — moves into territory that requires a careful look at your specific zone. Some zones allow it; others cap the total number of units.

Your first call should be to City of Moncton Planning & Development at (506) 856-4375 or email info.plans@moncton.ca. Ask them specifically: "What is my lot's zoning designation, and does it permit a garden suite in addition to an existing secondary suite?" They can pull up your civic address and give you a definitive answer — this is genuinely a five-minute phone call that saves months of headache.

A few things they'll look at beyond just the zone:

• Lot size and coverage — Moncton has maximum lot coverage rules. A garden suite (detached structure) adds to your total built footprint. Smaller urban lots may already be near the limit.
• Setbacks — The garden suite must respect rear and side yard setbacks. In older Moncton neighbourhoods with narrow lots, this can be the deal-breaker.
• Parking — Additional units typically trigger additional off-street parking requirements.
• Servicing — A garden suite needs its own or shared water/sewer connection. Moncton Planning will flag if your existing service has capacity.

If zoning does allow it, a garden suite is treated as a full construction project under the National Building Code of Canada 2020 (mandatory for new applications as of May 1, 2025, including Tier 2 energy efficiency requirements). You'll need a building permit from the City of Moncton, plus separate trade permits — an NB Power electrical wiring permit (1-800-615-0522) and inspections through NB Dept. of Justice and Public Safety Technical Inspection Services (1-888-659-3222) for electrical, plumbing, and any gas work.

Budget-wise, a modest garden suite in the Moncton market typically runs $150,000–$250,000+ depending on size, finishes, and whether you're connecting new services or tying into existing ones. That's a significant investment, but with Moncton's rental market, many homeowners find the numbers work — especially with NB Power rebates available for energy-efficient construction (heat pump, insulation to Tier 2 standards).

One practical tip: before you invest in architectural drawings, get the zoning confirmation in writing from the city. If your zone doesn't currently permit two accessory units, you'd be looking at a rezoning or variance application — a longer process but not impossible in Moncton's current planning environment.

Browse licensed contractors experienced with garden suite and secondary suite construction in our New Brunswick Construction Network directory to get a realistic sense of local costs and timelines once you have your zoning confirmed.