Composite vs PVC Decking for Calgary’s Freeze-Thaw Climate by Elevation Renovations—Professional Deck Builders in Calgary & Okotoks

Mike Bouchard
5 days ago
3 min read

Building a deck that survives Calgary’s wild weather?

Between deep-freeze winters, Chinook thaws, and blazing summers, outdoor materials in southern Alberta take a serious beating. If you’re investing in a new deck, choosing the right material—composite vs PVC—will decide how long it lasts, how much maintenance you’ll do, and how good it looks in year 10.

This local guide compares the two based on Calgary & Okotoks climate realities, cost, and performance—with insights from the team at Elevation Renovations.

[PHOTO: Beautiful composite deck in Calgary backyard with snow and sunlight]

🌦️ 1. Understanding Our Climate

Calgary’s temperature swings can exceed 40°C in a week. Decking materials expand and contract, coatings crack, and cheap boards warp. PVC and composite are both better than wood here—but they behave differently when it comes to:

Freeze-thaw cycles
Moisture absorption
UV resistance
Structural movement

Pro tip: Proper joist spacing and ventilation below the deck matter as much as the board choice.

🔬 2. What’s the Difference Between Composite and PVC Decking?

Feature	Composite	PVC (Polyvinyl Chloride)
Composition	Wood fibres + plastic	100% synthetic plastic
Look & feel	More natural wood grain	Smoother surface
Weight	Heavier	Lighter
Water absorption	Low	None
Fade resistance	Good	Excellent
Cost range (2025)	$14 – $22 / sq/ft installed	$16 – $26 / sq/ft installed
Maintenance	Soap and water wash 2× yearly	Minimal cleaning
Lifespan	25–30 years	30–40 years

❄️ 3. Performance in Calgary Winters & Chinooks

Composite:

Slightly porous—can absorb moisture at board ends.
Needs correct gapping (⅛") to handle expansion.
Feels warmer underfoot in cold weather.

PVC:

Fully waterproof—no rot or mould.
Can expand more in summer heat; use hidden fasteners for movement.
Resists freeze-thaw cracks and stains.

Both outperform treated wood or cedar when installed properly.

💸 4. Cost & Longevity in Alberta

Composite: Lower initial cost; solid brands like Trex or TimberTech offer 25-year warranties.
PVC: Slightly higher price but often a 50-year warranty and zero water damage.
Labour: Expect $20–$30 per sq/ft total installed price (depending on railing type and stairs).

In our Calgary projects, we’ve found PVC decks cost ~10–15 % more but save owners $1,000+ over 10 years in maintenance.

🧱 5. Installation & Framing Considerations

Use pressure-treated or metal framing for longer life.
Maintain a proper ventilation gap under the deck to reduce mould.
Use hidden fasteners for a clean look and thermal movement.
Seal all cut ends on composite boards to prevent swelling.

For a deeper technical overview, see the Alberta Building Code Deck Standards and the City of Calgary Residential Deck Guide.

🏠 6. Aesthetics & Design Trends for 2025

Homeowners in Calgary & Okotoks are leaning toward:

Two-tone PVC decks with aluminum railings.
Built-in lighting and privacy screens.
Low-rise steps to patios for multi-season use.

🧰 7. Choosing the Right Material for You

Choose composite if:

You prefer a warmer look & feel.
You want a mid-range budget with good durability.

Choose PVC if:

You want a deck that’s waterproof and nearly maintenance-free.
You value long warranties and maximum lifespan.

Whichever you pick, expert installation makes the real difference. Our Composite Decks Calgary specialists handle design, permits, and precise installation for year-round durability.

💬 8. FAQ – Common Deck Questions

Do I need a permit for my deck in Calgary? Yes—check the City of Calgary deck permit rules. Most raised decks require a permit over 0.6 m (24 in.) high.

Can I use PVC over an old wood frame? Only if the frame is structurally sound and properly vented. PVC is lighter but still requires solid support.

How long does deck installation take? Typical Calgary projects: 1–3 weeks depending on size, permits, and weather.

What about winter construction? Yes—we build year-round in Calgary and Okotoks with frost-protected methods.