How much does it cost to bring an unpermitted deck up to code in NB?

Bringing an unpermitted deck up to code in New Brunswick typically costs $2,000-$8,000 depending on what's wrong, but can reach $15,000+ if major structural work is needed. The exact cost depends on what code violations exist and whether the deck can be retrofitted or needs complete rebuilding.

The most common (and expensive) issues with unpermitted decks in NB are inadequate footings and improper ledger board attachment. Many older decks have footings that don't reach below our frost line — that's 1.2 metres deep in southern NB (Moncton, Saint John, Fredericton) and up to 1.5 metres in northern areas like Bathurst. Shallow footings will heave during freeze-thaw cycles, potentially causing deck collapse. Fixing this requires excavating new footings, which often means rebuilding the entire support structure.

Common code violations and typical costs:

Footing issues are the biggest problem. If footings are too shallow, you're looking at $1,500-$4,000 to excavate and pour new concrete footings below frost line. This often requires temporarily supporting the deck while work is done, adding to complexity and cost.

Ledger board problems are equally serious. Many unpermitted decks have ledgers that are nailed (not lag-bolted) to the house or lack proper flashing. Fixing this costs $800-$2,500 and involves removing siding, installing proper flashing, and re-attaching with structural lag bolts. This prevents the leading cause of deck collapse and house water damage.

Railing code violations are common but less expensive to fix. NB requires 36" high railings with balusters spaced no more than 4" apart when the deck is 24" or higher above grade. Bringing railings up to code typically costs $30-$60 per linear foot, so $1,200-$2,400 for an average deck perimeter.

Structural undersizing can be the most expensive fix. If joists, beams, or posts are too small for the span, you may need to add additional support or rebuild sections entirely. This can add $3,000-$8,000 to your project.

The permit process itself adds $100-$300 in fees plus the cost of having drawings prepared if none exist. Most municipalities will require an inspection before issuing a retroactive permit, and you'll need to bring everything up to current code — not the code from when it was built.

Timing considerations are crucial in NB. Footing work can only be done when the ground isn't frozen (typically May through October), and concrete needs temperatures above 10°C to cure properly. Plan any major structural work for summer months.

When to rebuild vs retrofit: If your deck has multiple major violations (shallow footings, undersized framing, improper ledger attachment), it's often more cost-effective to tear down and rebuild properly. A complete rebuild gives you a 25-year deck that meets all current codes, versus patching an old deck that may have other hidden issues.

Professional assessment is essential — structural problems aren't always visible, and attempting DIY fixes on load-bearing components can create safety hazards. A qualified deck builder can evaluate what's salvageable versus what needs replacement.

Need help finding a deck builder to assess your unpermitted deck? New Brunswick Decks can match you with local contractors who specialize in bringing older decks up to code safely and cost-effectively.