Can I turn my garage into a legal secondary suite in Dieppe NB?

Yes, it is possible to convert a garage into a secondary suite in Dieppe, but you must meet both the City of Dieppe's zoning requirements and the NB Building Code requirements for a self-contained dwelling unit. Secondary suites — sometimes called in-law suites, garden suites, or accessory dwelling units — are permitted in certain residential zones in Dieppe, but the rules around where they are allowed, how large they can be, and what building standards they must meet are specific and must be verified with the City of Dieppe's planning department before you begin any work.

The first step is confirming that your property's zoning designation permits a secondary suite. Not all residential zones in Dieppe allow secondary suites, and those that do may have restrictions on whether the suite can be in a detached garage versus an attached garage or within the main dwelling. Contact the City of Dieppe's planning and development office to confirm your property's zoning, whether a secondary suite is a permitted use or requires a variance, and what conditions apply. Some municipalities require that the property owner live in one of the two units — either the main house or the suite — rather than renting both.

NB Building Code Requirements for a Garage Suite

Converting a garage to a legal secondary suite triggers the full range of NB Building Code requirements for habitable space. The suite must have adequate ceiling height — a minimum of 2.3 metres (approximately 7 feet 6 inches) of clear height in habitable rooms. Many standard garages have 8-foot walls, which gives you just enough height after insulating and finishing the ceiling, but it is tight. If your garage ceiling is lower than this, the conversion may not be feasible without structural modifications.

The suite needs proper egress — at least one window in each bedroom that meets egress size requirements (minimum 0.35 square metres of openable area, with minimum dimensions of 380 mm in height and width), plus a proper entry door. Fire separation is critical: if the suite is in an attached garage, the fire-rated separation between the suite and the main dwelling must be maintained or upgraded. A detached garage suite has simpler fire separation requirements but must still meet minimum fire resistance ratings for its construction type.

Insulation must meet current NB energy code standards for a heated dwelling unit — walls at R-20 or higher, ceiling at R-40 or higher, and the concrete slab must be insulated or have a moisture management system. The suite needs its own independent HVAC system — a ductless mini-split heat pump is the most common and cost-effective choice for garage suites in NB, typically costing $3,500 to $6,000 installed. Electrical service must include its own circuits, GFCI protection, smoke and carbon monoxide detectors, and may require a separate electrical panel. All electrical work must be done by a licensed electrician with proper permits.

Plumbing for the kitchen and bathroom adds significant cost and complexity. The garage slab will need to be cut and excavated to run drain lines to the municipal sewer or your septic system. In Dieppe, connecting to the municipal water and sewer system requires permits and may involve connection fees. Septic systems, if applicable, must have capacity for the additional dwelling unit — an undersized septic system will need to be upgraded before the suite can be occupied.

The total cost for a legal secondary suite conversion from a two-car garage in Dieppe runs $35,000 to $55,000 for a well-executed project with kitchen, bathroom, proper insulation, and independent HVAC. This is a significant investment, but rental income in the Dieppe-Moncton area — typically $800 to $1,400 per month for a self-contained suite — provides a strong return over time.

This is absolutely a project that requires professional contractors. You will need a general contractor experienced in garage conversions, a licensed electrician, a licensed plumber, and potentially an HVAC technician. A building permit is required, and inspections will occur at multiple stages. Get matched with experienced local contractors through New Brunswick Garages — it is a free service through the New Brunswick Construction Network.