What is the average cost to replace a patio door in a New Brunswick home?

Replacing a patio door in a New Brunswick home costs $2,000-$6,000 installed for a standard sliding glass door, and $3,500-$8,500 for a French door configuration — with the wide range driven by door material, glass package, size, and whether any framing or structural repairs are needed around the opening.

Sliding patio doors are the most common and affordable option. A quality vinyl sliding door with double-pane low-e glass and argon fill runs $2,000-$3,500 installed by a Moncton or Saint John contractor. Upgrading to triple-pane glass adds $400-$800 to the cost and is increasingly worth it in NB's climate — the interior glass surface temperature on a triple-pane unit stays dramatically warmer in January, making the adjacent living or dining area significantly more comfortable in winter months. Fibreglass sliding doors are less common but offer superior dimensional stability through NB's freeze-thaw cycles — expect to pay $3,500-$6,000 installed for a fibreglass slider.

French doors — two hinged panels that swing open — cost more primarily because of hardware complexity and the seal quality required where the two panels meet in the centre. A multi-point locking mechanism is important on French doors to prevent flex and air infiltration along the meeting stile. Quality French patio doors start around $3,500 installed and climb to $7,000-$8,500 for premium fibreglass or wood-clad units with decorative glass, upgraded hardware, and built-in blinds between the glass panes. Built-in blinds are worth considering for south and west-facing patio doors in NB where afternoon sun can cause significant glare and heat gain in summer.

The installation is where hidden costs can arise. In homes built in the 1970s through 1990s, removing an old sliding door often reveals rot in the sill pan or the rough framing below the threshold — an extremely common issue when original drainage flashing was inadequate or the seal between the door frame and the exterior cladding has failed over the years. A proper patio door installation includes a sloped sill pan with integrated drainage to direct any incidental water away from the framing, flexible flashing tape integrated with the wall's water-resistive barrier, and sill sealer foam between the door frame and the sill. Skipping these details is how a new $3,000 door becomes a $12,000 problem five years later when the floor framing rots.

For homes in coastal NB communities — areas along the Bay of Fundy, Fundy Shore, or the Northumberland Strait — specify stainless steel hardware and marine-grade weatherstripping for any patio door. Standard hardware corrodes noticeably faster in salt air environments, and the weatherstripping seal is critical for keeping wind-driven rain out.

Permits are not required for a straight replacement patio door in the same opening, but if you're enlarging the opening or the patio door is in a load-bearing wall, a building permit and engineer's assessment are required. A reputable contractor will identify this upfront. Allow $500-$1,000 contingency in your budget for any framing repairs discovered during installation, particularly in homes over 25 years old. Get three quotes, ask each contractor specifically how they handle the sill flashing and framing inspection, and confirm WorkSafeNB coverage before signing anything.

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Looking for experienced contractors? The New Brunswick Construction Network connects homeowners with qualified professionals:

• Gionetterenovations
• Thirty Four Renovations