Guides
Composite vs. Pressure-Treated Decking: Cost and Durability Compared
If you're choosing between composite vs pressure-treated decking for a Calgary build, the honest answer is that neither one is simply "better" — pressure-treated costs less upfront and pressure-treated boards can be replaced individually if one warps; composite costs more upfront and needs far less maintenance over the life of the deck. Here's what that actually means in dollars and years, based on current Calgary-area pricing rather than national averages.
Which is better, composite decking or pressure-treated decking?
Neither wins outright — composite decking lasts longer and needs less upkeep, while pressure-treated wood costs less to install and is easier to repair board-by-board. The right choice depends on whether you're optimizing for the lowest cost this year or the lowest cost over the next 20 years.
How much more does composite decking cost upfront?
A composite deck typically runs $8,000–$11,000+ installed, compared to $5,000–$7,000 for a pressure-treated deck of similar size — roughly 40–60% more upfront for composite.
Verified against Windsor Plywood's Calgary-region deck cost guide, checked August 2026 (published April 2026).
These are installed project costs including labour and materials, not raw lumber prices. Most small-to-mid-size decks fall in the $5,000–$13,000+ range depending on material and design.
How long does each material actually last?
Pressure-treated lumber has an expected lifespan of 15–20 years; composite decking is rated for 25+ years by the same source. That's the trade-off underneath the price gap — composite's higher upfront cost buys roughly 5–10 more years before replacement.
Verified against Windsor Plywood's Calgary-region deck cost guide, checked August 2026 (published April 2026).
What's the actual cost comparison, side by side?
| Pressure-treated | Composite | |
|---|---|---|
| Installed cost (typical Calgary deck) | $5,000–$7,000 | $8,000–$11,000+ |
| Expected lifespan | 15–20 years | 25+ years |
| Maintenance | Staining/sealing every 1–2 years | Occasional washing, no staining |
Verified against Windsor Plywood's Calgary-region deck cost guide, checked August 2026 (published April 2026).
Our deck builders page cites a different source (HomeStars) with higher numbers — that's not a typo. Windsor Plywood's figures above are general "typical Calgary deck" ranges; HomeStars' are pegged specifically to a 200 sq. ft. deck. Different scope, not a contradiction.
What's the maintenance difference over time?
Pressure-treated wood needs staining or sealing roughly every 1–2 years to keep it from graying, splitting, or absorbing moisture — skip that and the lifespan drops well below the 15–20 year range above. Composite doesn't need staining at all; the maintenance is closer to periodic washing, which is the main reason it costs less to own over a full deck lifespan even though it costs more to build.
What's the downside of composite decking?
Composite costs more upfront, and it can get noticeably hotter underfoot in direct summer sun than wood does — a real consideration on a south-facing Calgary deck. It's also not repairable board-by-board the way pressure-treated is: a damaged composite board usually means a full replacement of that section, not a quick swap.
Which one should you choose for a Calgary deck?
Both materials have to handle the same Calgary-specific stress: repeated freeze-thaw cycling from chinooks, where temperatures can swing 20+ degrees in hours. Pressure-treated lumber handles that if it's properly stained and sealed on schedule; skip the maintenance and the freeze-thaw cycling finds every gap. Composite doesn't need that maintenance discipline to hold up, which is the practical argument for it in a climate where a missed staining season is easy to let slide.
Ready to build?
Every deck we build starts with a 3D render you approve before anything is cut, and we'll walk you through the real cost difference for your specific deck size and design — not a generic per-square-foot number. See our Calgary deck builders page for how the process works, or check our Calgary deck permit guide if you're not sure whether your project needs one.
Get a free design consultation — no obligation, response within one business day.