Budgeting · 7 min read
Pressure-treated or composite: what a deck actually costs
Pressure-treated vs composite deck cost in Canada: the Ottawa package near $12,350, and why the board upcharge is not 40 percent of the invoice.
The board is what you argue about in the aisle. The invoice is footings, a ledger flashed into the house, a guard, and a stair. Composite can be the right surface and still be the smaller line if the deck is high or the old one has to come out.
Our deck calculator prices a whole small deck, not a bundle of boards. Ottawa is the 1.00 region. The default package is 12 by 16 feet, 192 square feet, pressure-treated lumber, between two and six feet off the ground, a wood guard, one short flight of stairs, a permit allowance, and contingency. On a detached house built from 1960 to 1989, at mid-range quality, that lands near $12,350 typical. The same package in composite lands near $16,200. Cedar is near $13,800. PVC or a premium composite is near $18,150. This is a planning range, not a quote.
What the $8,000 deck actually is
A basic 200 square foot pressure-treated deck is quoted near $8,000 in Toronto, about $40 a square foot, and published Toronto ranges run from about $40 to $160 a square foot once height, railing, and material change. The model was checked against that band. The stripped case in Ottawa, ground level, no guard, no stairs, still carrying the permit allowance and contingency, is about $8,250. That is the deck people mean.
The default package is about $64 a square foot all-in, because the guard, the stairs, the height, and the contingency are in it. A deck you can fall off is not the stripped case.
The 1.4 switch is not a 40 percent invoice
In the model, composite is 1.4 times pressure-treated and PVC is 1.6, applied to the body of the deck. The permit allowance and the flat price of the stair flight do not scale with the board. That is why $16,200 is about a third more than $12,350, not 40 percent more.
On a real quote the footings, the local frost depth, and most of the frame barely change when the walking surface changes. The boards, the hidden fasteners, and a picture-frame border are the upcharge. If the only difference between two quotes is the board brand and the total jumped 40 percent, ask what else moved.
What wood still costs after the crew leaves
Pressure-treated lumber is the cheaper build, and it needs a stain cycle. Skip a dry weekend and the boards cup. Composite skips that cycle. It does not skip the structure. Under a composite deck in Canada the frame is still usually pressure-treated or steel, the footings still have to get below local frost depth, and the ledger still has to be flashed so the house wall does not rot behind the new boards.
There is no honest yearly stain number to print here. It depends on the exposure and on whether anyone does the work. Price that habit, or price the composite.
Framing lumber has been flat, close to where it was a year ago, and far below the pandemic peaks. Hangers, bolts, and an aluminum rail are steel, and steel has not been flat. Do not budget the lumber as if it were still spiking, and do not budget the hardware as if it were lumber.
Height, and the permit
Many municipalities want a permit once a deck is attached to the house, once it needs a guard, or once the area crosses a local limit. Toronto and Ottawa do not share one threshold. Treat an attached deck as a permit check. The default package includes a permit allowance of about $1,500 in Ottawa, inside the $12,350, not stacked on top of it.
Dropping from the two-to-six-foot height down to a ground-level platform, and keeping the wood guard and the short stair, brings the same materials to about $11,350. Taking the guard and the stair off as well is how the number falls toward the basic deck. That comparison is only honest if nobody can step off the edge.
How to read two quotes that are not the same deck
- Write the footprint in feet, and the height off the grade.
- Split the quote into frame and footings, walking surface, guard, and stairs.
- Ask if the old deck is in the price. Removal is off in our default.
- Ask who pulls the permit, and whether a footing inspection is included.
- Keep the structure identical and change only the board. The gap you see then is the real upcharge.
- If you will not stain it, price composite. If you will, pressure-treated is the cheaper deck, and the maintenance is the cost that was not on the invoice.
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