Updated October 2026
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There is no single sticker price for a deck, and any Ottawa builder who gives you one over the phone before seeing your yard is guessing. What we can do is show you the honest ranges, explain exactly what moves the number, and tell you how we arrive at a real, project-specific price instead of a made-up one.
How much does a deck cost in Ottawa?
Across Canada in 2026, a new deck typically costs between $35 and $130 per square foot, installation included (RenoQuotes' national range, not a quote), and the single biggest lever is the material you choose. Pressure-treated is cheapest, cedar sits in the middle, and composite or PVC cost the most up front in exchange for almost no maintenance.
For a sense of a whole project rather than a per-foot figure, a standard 12 by 12 foot deck (144 square feet) starts around $5,500 for pressure-treated wood and climbs to $18,000 or more for a premium composite build with glass railings and helical piles. Both are a national range, not a quote.
If you are replacing rather than building new, a resurface over sound framing runs a different range again (roughly $5,000 to $15,000), while a full tear-down and rebuild is more like $15,000 to $50,000, depending on size and material.
Ranges this wide are exactly why we do not publish a price list. Here is how the four deck materials we build in compare, using RenoQuotes' 2026 figures, each a national range, not a quote (aluminium framing and railing systems run higher again, at roughly $95 to $135 per square foot):
| Material | Installed cost per sq ft | What you are paying for |
|---|---|---|
| Pressure-treated wood | $35 to $60 | The most affordable, code-built structure. Needs cleaning and re-staining every couple of years. |
| Western red cedar | $60 to $90 | Warm natural wood, cooler underfoot. Re-oil every couple of seasons or let it silver. |
| Composite (Trex, Fiberon, TimberTech) | $100 to $130 | No sanding, sealing or staining. Colour holds through freeze-thaw. |
| PVC (Azek, Clubhouse) | $100 to $130 | Fully synthetic, lightest and most moisture-proof. Strongest choice beside a pool. |
Source: RenoQuotes: Deck Cost in Canada 2026 · Ottawa Contractors: deck transformation guide
What does a 20x20 deck cost, and can you build one for $5,000?
A 20 by 20 foot deck is 400 square feet. At RenoQuotes' 2026 installed figures, that works out to $14,000 to $24,000 in pressure-treated wood, $24,000 to $36,000 in cedar, and $40,000 to $52,000 in composite or PVC. Each is a national range, not a quote, worked as 400 square feet times the installed range for that material.
A 20x20 composite or PVC deck works out to $40,000 to $52,000 installed, at RenoQuotes' $100 to $130 per square foot (national range, not a quote). The same deck in pressure-treated wood is $14,000 to $24,000, so composite adds $16,000 to $38,000.
RenoQuotes' per-foot figures cover framing, decking and basic labour, and it prices railings and stairs on top: $80 to $150 per linear foot for aluminium picket railing, $150 to $400 for aluminium and glass, and $400 to $700 for a 3- to 4-step pressure-treated staircase.
A 20x20 set against the house has up to 60 feet of open edge, so picket railing along all of it adds $4,800 to $9,000. That is also a national range, not a quote.
A $5,000 budget builds a small deck at most. At RenoQuotes' $35 floor for pressure-treated wood it covers about 143 square feet, and at the $60 top of that range about 83. A 12 by 12 is 144 square feet, and RenoQuotes starts that size at around $5,500 (national range, not a quote).
A 10 by 10 fits inside $5,000 only if the job prices at $50 a square foot or less, and in composite the same money covers 38 to 50 square feet.
Removing an old deck comes out of the same budget. RenoQuotes puts demolition and disposal at $500 to $1,500 or more (national range, not a quote).
| Material | Installed per sq ft | 20x20 deck (400 sq ft) | What $5,000 covers |
|---|---|---|---|
| Pressure-treated wood | $35 to $60 | $14,000 to $24,000 | About 83 to 143 sq ft |
| Western red cedar | $60 to $90 | $24,000 to $36,000 | About 56 to 83 sq ft |
| Composite or PVC | $100 to $130 | $40,000 to $52,000 | About 38 to 50 sq ft |
What does a 12x12, 12x16, 12x24, 16x20 or 20x20 deck cost?
The table below works RenoQuotes' 2026 installed ranges out for five common deck sizes. Each cell is the area times the per-square-foot range for that material: $35 to $60 for pressure-treated wood, $60 to $90 for western red cedar and $100 to $130 for composite or PVC. They are national ranges, not an Ottawa price and not our quote.
RenoQuotes' per-foot figures cover framing, decking and basic labour. Railings and stairs come on top, and so does taking out an old deck. Height above the grade, the footings Ottawa ground needs and any City of Ottawa permit drawings also move the real number, which is why we price a deck from the 3D design you approve.
| Deck size | Area | Pressure-treated wood | Western red cedar | Composite or PVC |
|---|---|---|---|---|
| 12 x 12 ft | 144 sq ft | $5,040 to $8,640 | $8,640 to $12,960 | $14,400 to $18,720 |
| 12 x 16 ft | 192 sq ft | $6,720 to $11,520 | $11,520 to $17,280 | $19,200 to $24,960 |
| 12 x 24 ft | 288 sq ft | $10,080 to $17,280 | $17,280 to $25,920 | $28,800 to $37,440 |
| 16 x 20 ft | 320 sq ft | $11,200 to $19,200 | $19,200 to $28,800 | $32,000 to $41,600 |
| 20 x 20 ft | 400 sq ft | $14,000 to $24,000 | $24,000 to $36,000 | $40,000 to $52,000 |
What actually drives the cost of your deck
Four things account for most of the spread, and size is only one of them.
Size. More square footage means more material and more labour. This is the obvious one, but it is not the biggest swing on a small deck.
Material tier. As the table shows, moving from pressure-treated to composite roughly doubles the per-foot cost. You are buying down future maintenance, not just a look. Over 8 to 12 years, most homeowners recover the composite premium in the staining and sealing they never have to do. We build decks in Ottawa in all four materials, and the same crew builds whichever one you choose.
Structure. A ground-level rectangle is the cheapest thing we can build. A second level, built-in stairs, custom railings (glass or aluminium), lighting, or a pergola on top each add labour and material well beyond the deck surface itself.
Permits and site conditions. A deck that needs a City of Ottawa building permit carries the added time of drawings and an application. Grade, drainage and access to the yard also affect how the base and footings have to be built, especially for Ottawa's freeze-thaw ground movement. We cover this in full in our Ottawa deck and fence permit guide.
Why Ottawa's climate changes the maths
Ottawa runs through dozens of freeze-thaw cycles a year, and that is hard on a deck. It is why we set footings below the frost line, though depth alone does not stop heave, because frozen clay grips the sides of a pier. It is also a real argument for composite or PVC boards, which resist the moisture, rot and fading that put wood decks on a re-staining schedule.
A cheaper wood deck can cost more over ten years once you count the upkeep. We walk you through that trade-off for your specific yard rather than pushing the most expensive board. And if a patio makes more sense than a deck for part of your yard, the same freeze-thaw logic shapes our interlock patios and walkways too.
How we price a deck, and why it is honest
The ranges above are national. We price decking in Ottawa against your own yard: its grade, its drainage and the footings it needs below the frost line.
Every project is modelled in 3D and AutoCAD before a single board is cut. That means when we give you a price, it is tied to the exact layout, material, railing, stair and lighting choices you have already seen and approved, not a rough guess that balloons later. You get one project-specific number.
If it helps to spread that number out, financing is available through our third-party partner iFinance (any figure we mention in conversation is illustrative only, not an offer of credit).
Common questions
How much does a composite deck cost in Ottawa?
Published 2026 Canadian ranges put installed composite and PVC decking at roughly $100 to $130 per square foot, versus $35 to $60 for pressure-treated and $60 to $90 for cedar. These are national industry ranges, not an Ottawa Decking Solutions quote. Because size, structure, railings, lighting and permits all move the number, we design your deck in 3D first and then give you one honest, project-specific price.
What does a 12 by 12 deck cost in Ottawa?
For a 144-square-foot deck, published 2026 Canadian ranges start around $5,500 for a pressure-treated build and climb to $18,000 or more for a premium composite deck with glass railings and helical piles (national range, not a quote). Your real number depends on the material, the structure and whether the project needs a City of Ottawa permit, which is why we quote per project rather than from a price list.
Why won't Ottawa Decking Solutions give a price over the phone?
Because an honest deck price depends on the yard, the base and drainage conditions, the material tier, and the exact design. We design every deck in 3D and AutoCAD first so you can see and approve the layout, then give you one project-specific price tied to that design, and financing is available through our third-party partner iFinance if it helps spread the cost.
How much would a 20x20 deck cost?
A 20x20 deck is 400 square feet. RenoQuotes' 2026 installed figures put it at $14,000 to $24,000 in pressure-treated wood, $24,000 to $36,000 in cedar, and $40,000 to $52,000 in composite or PVC, before railings and stairs. That is a national range, not a quote. We price your deck from the design you approve.
Can you build a deck for $5,000?
Only a small one. At RenoQuotes' 2026 range of $35 to $60 per square foot for pressure-treated wood (national range, not a quote), $5,000 covers about 83 to 143 square feet, just under the 144 square feet of a 12 by 12. In composite it covers 38 to 50 square feet.
How much does a 12x16 deck cost?
A 12x16 deck is 192 square feet. At RenoQuotes' 2026 installed figures that is $6,720 to $11,520 in pressure-treated wood, $11,520 to $17,280 in cedar and $19,200 to $24,960 in composite or PVC, before railings and stairs. That is a national range, not a quote.
How much does a 12x24 deck cost?
A 12x24 deck is 288 square feet. At RenoQuotes' 2026 installed figures that is $10,080 to $17,280 in pressure-treated wood, $17,280 to $25,920 in cedar and $28,800 to $37,440 in composite or PVC, before railings and stairs. That is a national range, not a quote.
How much does a 16x20 deck cost?
A 16x20 deck is 320 square feet. At RenoQuotes' 2026 installed figures that is $11,200 to $19,200 in pressure-treated wood, $19,200 to $28,800 in cedar and $32,000 to $41,600 in composite or PVC, before railings and stairs. That is a national range, not a quote.