How much does a full garage-to-living-space conversion cost in Saint John NB?

A full garage-to-living-space conversion in Saint John typically costs between $15,000 and $50,000, depending on the scope of work, whether you are adding plumbing, and the current condition of the garage. A basic conversion — insulation, drywall, flooring, electrical upgrades, and a window or two — runs $15,000 to $30,000 for a standard two-car garage. Adding a bathroom pushes the total to $25,000 to $40,000, and a fully self-contained garage suite with kitchen, bathroom, separate entrance, and independent HVAC can reach $35,000 to $50,000 or more.

The biggest cost drivers in a Saint John garage conversion are insulation and moisture management. Saint John's coastal Maritime climate brings persistent humidity from the Bay of Fundy, and the city's winters regularly dip to -20 degrees Celsius with significant wind chill. Your garage walls will need a minimum of R-20 insulation, and the ceiling should be insulated to R-32 or higher if there is an attic space above. Closed-cell spray foam at $3.50 to $7.00 per square foot installed is the premium choice because it provides both insulation and a vapour barrier in one application, but fibreglass batts with a properly installed 6-mil poly vapour barrier at $1.50 to $3.00 per square foot are a more budget-friendly option that performs well when done correctly.

The concrete slab is often the most challenging element of the conversion. Most garage slabs in Saint John were poured without a vapour barrier underneath and sit 4 to 8 inches below the main house floor level. You will likely need to address moisture coming through the slab by installing a dimpled membrane or applying a moisture-mitigating primer before laying flooring. For the floor itself, expect to spend $3 to $8 per square foot depending on whether you choose vinyl plank, laminate, or engineered hardwood. If the slab is uneven, self-levelling compound adds $2 to $4 per square foot.

Saint John has specific considerations that affect conversion costs. If the garage is attached to the house, the existing fire separation wall between the garage and the dwelling must be maintained or reconfigured to meet current NB Building Code requirements — this means 5/8-inch Type X fire-rated drywall on the garage side of common walls, with all penetrations properly fire-stopped. If you are converting the entire garage to living space and removing the garage function, the fire separation requirements change, but you will need to discuss this with your local building inspector. A building permit is required for any garage conversion in Saint John, and electrical work requires a separate electrical permit and must be done by a licensed electrician.

Practical cost breakdown for a typical Saint John two-car garage conversion (approximately 400 to 500 square feet): insulation and vapour barrier $2,500 to $5,000, drywall and finishing $3,000 to $5,000, electrical upgrades including sub-panel and additional circuits $1,500 to $4,000, flooring $1,500 to $4,000, window installation (typically two windows for light and egress) $1,500 to $3,000, HVAC extension or mini-split installation $2,500 to $5,000, and painting $500 to $1,500. These numbers add up to roughly $13,000 to $27,500 in direct costs, with contractor overhead, profit, and permit fees pushing the total to the $15,000 to $30,000 range for a basic conversion.

A garage conversion is not a good DIY project in its entirety — the electrical, HVAC, and structural components all require licensed professionals. However, homeowners can save $1,000 to $3,000 by doing their own painting, installing shelving and trim, and handling cosmetic finishing after the professionals complete the structural, mechanical, and electrical work. Get at least three quotes from local contractors and make sure each quote includes the same scope so you can compare fairly. Need help finding a professional for your Saint John garage conversion? New Brunswick Garages can match you with local contractors for free through the New Brunswick Construction Network.