What percentage of garage build cost should I set aside for contingencies in NB?

Set aside 15-20% of your total garage budget as a contingency reserve for a New Brunswick build — slightly higher than the 10-15% rule of thumb you'll see in general construction guides, and for good reasons specific to this province.

NB's climate and ground conditions introduce variables that simply don't exist in milder parts of Canada. The most common budget surprises on NB garage projects fall into a predictable pattern, and understanding them helps you plan realistically rather than getting caught off guard mid-build.

Soil and foundation surprises are the biggest contingency driver in New Brunswick. Once excavation begins, contractors regularly encounter unexpected rock ledge, high water tables, soft organic fill, or old buried debris — especially on older residential lots in established neighbourhoods in Moncton, Saint John, and Fredericton. Blasting or breaking rock adds $2,000-$8,000 to a project almost overnight. Encountering soft soil that requires additional compacted gravel fill or deeper footings can add $1,500-$5,000. You won't know what's under your lawn until the excavator is already there, which is exactly why contingency money needs to be liquid and accessible before you start.

Lumber and material price volatility is a real factor in NB. SPF framing lumber prices have swung dramatically in recent years, and if your project spans more than a few weeks from quote to completion — which most garage builds do — material costs can shift. A contractor who quoted you in April based on current lumber pricing may face higher costs by the time framing begins in June. Some NB contractors include material escalation clauses in their contracts; others absorb the risk. Either way, having contingency funds available protects you if the contract requires renegotiation.

Weather delays and seasonal complications add cost. A concrete pour delayed by an unexpected cold snap in May or October may require heated enclosures, concrete accelerators, or rescheduling that affects the entire trade sequence. If your project runs into late fall, roofing and siding in cold conditions adds labour cost. These aren't catastrophic events — they're normal NB construction realities — but they cost money.

Scope changes are the most controllable contingency risk. Homeowners frequently decide mid-build to add insulation they hadn't planned for, upgrade to an insulated garage door, add a sub-panel for future EV charging, or extend the slab for a small storage alcove. These are good decisions, but they cost money. If you already know you might want these upgrades, price them into your initial scope rather than treating them as contingencies — your contractor will give you a better price if they're included from the start rather than added as change orders.

A practical way to structure your contingency: Keep 10% as a true emergency reserve (foundation surprises, weather events, material escalation) and treat the other 5-10% as a "scope flexibility" fund for upgrades and additions you're genuinely considering. If you finish the project and haven't touched the emergency reserve, that money can go toward a floor coating, a gas heater, or better lighting — all things that make a NB garage genuinely usable through a six-month winter.

For a $60,000 two-car garage build, that means keeping $9,000-$12,000 in reserve before you break ground. It feels conservative until the excavator hits ledge rock on day one.

If you're working with a fixed-price contract (which most reputable NB garage contractors offer), your contingency exposure is lower on materials and labour — but you're still exposed on permit revisions, site conditions discovered during excavation, and any scope changes you initiate. Even with a fixed-price contract, 10-15% contingency is prudent.

Need help finding a garage contractor who can give you a detailed, itemized quote before you commit to a budget? New Brunswick Garages can match you with local builders at no cost — a thorough quote is the best tool for understanding where your contingency risks actually live on your specific project.