Can I use bagged concrete mix for a small patio in NB?

Bagged concrete mix works for very small projects — sonotube footings, fence posts, repair fills — but is not practical or economical for even a modest patio in New Brunswick. For anything larger than about 20 square feet, ready-mix is the better choice.

The math tells the story. Bagged concrete mix (Quikrete, Bomix, or similar) is sold at NB building supply stores in 30 kg bags for $5–$8 each. One 30 kg bag yields approximately 0.014 cubic metres (0.5 cubic feet) of concrete. A small patio — say 8×8 feet (64 sq ft) at 4 inches thick — requires roughly 0.8 cubic metres, or about 57 bags. At $6–$7 per bag, that is $340–$400 in materials alone. Ready-mix delivered to your Moncton, Fredericton, or Saint John address for the same volume costs $170–$210, including a short-load surcharge. And you have to mix every one of those 57 bags by hand or with a rented mixer.

For a true small project — a 4×4 foot landing, a single sonotube footing, a patch fill — bagged concrete is perfectly appropriate. One to five bags, a wheelbarrow, a mixing hoe, and an hour of your time. The convenience and no minimum order requirements make it ideal for tasks that do not justify calling a ready-mix truck.

One important limitation for NB homeowners: most bagged concrete mixes are not air-entrained. If you are mixing bags for a small exterior slab that will be exposed to NB winters, you are working with concrete that lacks the freeze-thaw protection that air entrainment provides. For a fence post footing below grade, this is inconsequential. For a small exposed landing, steps, or patio — even a small one — you are taking on the risk of surface spalling within a few winters.

Some suppliers carry or can order air-entrained bagged mixes. If you are mixing bags for an exposed exterior surface, ask specifically for an air-entrained product, or plan to apply a quality penetrating sealer and accept that the surface may have a shorter service life than a ready-mix air-entrained pour.

The practical threshold: if your project requires more than 10–15 bags, call a ready-mix plant. The minimum order charge ($75–$150 short-load surcharge) is offset by the time you save, the better concrete you get, and your arms not falling off. New Brunswick Concrete can help you find contractors who handle small pours without the full production mobilization cost.