The best concrete contractors in Ottawa are the ones who specify their mix on paper — a minimum 32 MPa air-entrained mix with 5–8 percent air content for exterior flatwork — pour on a properly compacted granular base, use rebar or mesh where it matters, cut control joints within 24 hours, and cure and seal correctly. Ottawa's roughly 60 to 100 annual freeze-thaw cycles and heavy road-salt exposure destroy under-specified concrete within a few winters, so the mix and the base matter far more than the crew's price per square foot. There is no official ranking of Ottawa concrete companies, so the...
In Ottawa, the difference between concrete that lasts thirty years and concrete that spalls after three winters is usually written on the ready-mix ticket. Exterior flatwork exposed to freeze-thaw and de-icing salts should be a minimum 32 MPa air-entrained mix with roughly 5 to 8 percent entrained air, which creates microscopic voids that give freezing water somewhere to expand. Some contractors quote a cheaper 25 MPa non-air-entrained mix intended for interior slabs, which saves them a few hundred dollars on a driveway and costs you the whole slab. A quality contractor will also refuse to add water to the truck on site to make the mix easier to place, because excess water reduces strength dramatically. Ask for the mix specification in the written quote and ask for a copy of the delivery ticket on pour day — a professional hands it over without hesitation. This single request filters out a large share of low-bid crews before you ever compare prices.
New concrete should be kept moist or covered with a curing compound for several days, and Ottawa slabs should not be sealed until they have cured — commonly around 28 days for a penetrating sealer. Sealing every two to three years with a quality penetrating sealer meaningfully extends life against road salt.
Concrete fails from the bottom up more often than from the top down. A proper Ottawa driveway needs excavation to remove topsoil and organics, followed by 6 to 12 inches of compacted granular A base placed in lifts and compacted with a plate tamper or roller — not simply dumped and levelled. Much of Ottawa sits on Leda clay, which shrinks and swells dramatically with moisture, so drainage and base depth are not optional extras here. Reinforcement should be specified: a driveway carrying vehicles typically warrants 10M rebar on 16–24 inch centres or heavy wire mesh properly chaired up into the middle of the slab, not laid on the ground and hoped for. Slab thickness matters too — 4 inches is adequate for walkways and patios, but a driveway should be 5 to 6 inches, thicker at the apron where vehicles turn. Control joints should be saw-cut or tooled within about 24 hours at spacings roughly 24 to 30 times the slab thickness, so cracking happens where you decided rather than at random.
Anything structural — porch piers, steps tied to the house, garage slabs with foundations — needs footings below Ottawa's frost line of roughly 1.5 metres. Flatwork floats on its base, but attached steps and stoops that are not properly footed will heave and separate from the house within a couple of winters.
In 2026 Canadian dollars, plain broom-finished concrete in Ottawa typically runs $12–$20 per square foot installed, including excavation, base, reinforcement, and finishing. Exposed aggregate generally runs $18–$26 per square foot, and stamped or decorative coloured concrete $22–$35 per square foot depending on pattern complexity and colour method. A typical two-car driveway of 600–700 square feet therefore lands around $8,500–$14,000 plain and $14,000–$24,000 stamped. A 200 square foot patio commonly runs $2,800–$5,000 plain. Removal and disposal of an existing concrete or asphalt driveway usually adds $3–$7 per square foot, more if it is reinforced or unusually thick. Additional line items include exposed rock or excess excavation, a new drainage swale, thickened edges, integral colour, and sealing (about $0.75–$1.75 per square foot). Small pours carry proportionally higher pricing because a short-load charge from the ready-mix supplier and a full crew day apply regardless of area.
A bid that is 30 percent under the others is normally missing base depth, reinforcement, air entrainment, or all three. Replacing a failed driveway costs the full price again plus removal, so the savings evaporate the first time it spalls.
Ottawa's pouring season generally runs from late April through late October, and the shoulder months require care: concrete placed below about 5 degrees Celsius needs heated blankets, accelerators, or hoarding to cure properly, all of which add cost. Mid-summer pours have the opposite problem — a hot, windy July afternoon can flash-set the surface and cause plastic shrinkage cracking, so professionals pour early in the morning and use evaporation retarders. Book early, because the best Ottawa concrete crews fill their calendars by March. On permits, a straightforward replacement driveway or backyard patio at grade typically does not require a building permit, but you generally need a City of Ottawa permit for a new or widened driveway entrance where it crosses the City right-of-way, and structural elements such as porches, steps, and retaining walls above certain heights do require permits. Ontario One Call locates are free and legally required before any excavation, and they take several business days — factor that into the schedule.
Ask three contractors to quote the same square footage, thickness, base depth, reinforcement, and finish, and reject any quote that omits those details. Verify WSIB clearance and general liability insurance, and confirm the company has been operating locally for more than a season or two — concrete failures show up in year two or three, so a firm with a five-year Ottawa track record and driveways you can go look at is worth more than a new outfit with a slick website. Ask directly: What MPa and air content? How deep is the base and how is it compacted? What reinforcement and at what spacing? When are control joints cut? What is the warranty, and does it cover surface spalling? Reasonable Ottawa contractors warranty workmanship for one to five years but generally exclude hairline cracking, which is normal in concrete. Avoid large cash deposits and door-to-door crews with leftover material from another job. Browse screened concrete pros in our /directory and request free, no-obligation quotes to compare specifications side by side.
No official ranking exists. The best Ottawa concrete contractors specify a minimum 32 MPa air-entrained mix in writing, excavate and compact a proper granular base, install rebar or chaired mesh, cut control joints within about 24 hours, cure correctly, carry WSIB and liability coverage, and can show you local driveways they poured several years ago. Compare three quotes on the same specification.
Plain broom-finished concrete runs about $12–$20 per square foot installed, so a typical 600–700 square foot two-car driveway costs roughly $8,500–$14,000. Stamped or decorative concrete runs $22–$35 per square foot, putting the same driveway at about $14,000–$24,000. Removing an existing driveway adds $3–$7 per square foot.
Exterior flatwork in Ottawa should use a minimum 32 MPa air-entrained mix with roughly 5–8 percent air content to resist freeze-thaw damage and road salt. Ask for the mix specification in the quote and request the ready-mix delivery ticket on pour day.
Driveways should be 5 to 6 inches thick over 6 to 12 inches of compacted granular A base, with thickened edges at the apron. Walkways and patios are typically 4 inches. Reinforcement with 10M rebar on 16–24 inch centres or properly chaired mesh is recommended for vehicle traffic.
Replacing an existing driveway or pouring a backyard patio at grade usually does not require a building permit, but a new or widened driveway entrance crossing the City right-of-way requires City of Ottawa approval, and porches, steps, and taller retaining walls require permits. A free Ontario One Call locate is legally required before excavating.
Late April through late October is the practical season. Late-fall pours below about 5 degrees Celsius require blankets, accelerators, or hoarding, which adds cost, and hot windy summer afternoons risk surface cracking. Book early because good crews fill their schedules by March.