Overview: Deck Builders
A Canadian deck is built for frost before it's built for barbecues. Footings go below the local frost depth, onto soil nobody has dug. Precast blocks sitting on the surface rise and drop with each winter until the patio door starts to catch. Helical piles, screwed down by machine, are the usual answer where digging is hard.
The ledger, where the deck meets the house, carries much of the load. It needs through-bolts and flashing, because meltwater sits against that wall for months and rots whatever it reaches. Plenty of builders avoid the joint entirely by standing the deck on its own posts.
Permit rules are municipal, and the trigger moves. Calgary wants a permit for any covered deck and for an open one that rises above a low set height. If you hire the job out, the contractor applies. Toronto skips the permit for a low, uncovered deck that meets zoning and isn't part of a required exit. In Ontario, someone has to request free locates through Ontario One Call before a footing hole or pile goes in.
Our listings show what each deck company states on its own website. Use the province and city lists to reach the builders who frame and board decks in your area.
Frequently asked questions
What holds a deck onto the house?
A ledger bolted through the rim joist, with flashing tucked in above it and sealed where the bolts pass through. Nails alone won't do it. That joint is where decks tear away from houses. Winter makes it worse, since snow piles against the wall and meltwater finds any gap. Many builders here sidestep it with a free-standing frame on its own posts and footings.
Does a deck need a permit?
Usually, once it's covered or stands above a low height, though each municipality draws the line itself. In Calgary, the inspector comes once the frame, railings and stairs are done and needs to see the beams, posts and joists from below. Skirting that goes on too early gets in the way. An unpermitted deck tends to come up again when you sell the house.
How deep should deck footings go?
Below the frost depth for your area, which runs deep in most of the country, and onto undisturbed ground. Short footings heave, and the frame racks a little more each year. Helical piles reach depth without a big hole. In Calgary, some designs, screwpile foundations among them, need drawings stamped by a professional engineer. Your building department will give you the local frost depth.
What should happen to the old deck when it's torn out?
It shouldn't end up in the fire pit. Health Canada says never to burn treated wood, indoors or out, because the smoke and ash carry the chemicals. Whoever cuts it should wear a dust mask, eye protection and gloves. Offcuts, sawdust and the old boards go out under local disposal rules. Ask the crew where the demolition lumber ends up before you sign.
What do railings and stairs have to meet?
Guard height, baluster spacing and the push a guard has to resist all come from the building code. Calgary, for one, asks for a taller railing once a deck sits high off the ground. Stairs need even risers, a rail you can grip and a base that won't sink when the ground thaws. Inspectors bring a tape measure, and railings that miss get rebuilt.
How much upkeep does a deck need?
Sweep the board gaps before winter so meltwater drains, then again in spring. Shovel with a plastic blade along the boards. Once a season, check the ledger, flashing, hardware and post bases. An older treated deck was likely built with CCA, an arsenic-based preservative no longer sold for home projects. Health Canada suggests sealing that wood regularly and washing children's hands after they play on it.
