It’s the first big decision on every deck project: pressure-treated wood or composite? There’s no universal answer — but there is a right answer for your yard, your budget, and how many weekends you want to spend holding a stain brush. Here’s an honest comparison from a builder who works with both.

Upfront Cost

Pressure-treated (PT) lumber is the value champion. For the same-sized deck, PT typically runs 30–50% less than composite once installed.

Composite decking (Trex, TimberTech, and similar) costs more up front — the boards themselves run several times the price of PT — but railings, fasteners, and framing costs stay comparable.

Maintenance Reality

This is where the decision usually gets made:

PT decks need staining or sealing roughly every 2–4 years in Calgary’s climate. Skip it and boards grey, crack, and cup. That’s real recurring cost: either your weekends or $800–$1,500 per treatment.
Composite needs soap and water. No staining, no sealing, ever. Dirt washes off; colour is manufactured all the way through the board.

Over a 15-year horizon, the total cost of ownership often converges — you pay either in upfront materials or in ongoing maintenance.

How Calgary Weather Treats Each Material

Our chinook cycles deserve special mention. Going from deep freeze to plus-double-digits and back stresses materials through constant expansion and contraction.

PT wood handles the cycles well when properly sealed — the sealer is doing the moisture management, so keeping up with it matters.
Composite is dimensionally stable and doesn’t rot, but dark-coloured composites get genuinely hot in direct summer sun and can show thermal expansion gaps if installed without proper spacing (a builder issue, not a material issue).

Lifespan

Well-maintained PT deck: 15–25 years
Quality composite deck: 25–30+ years, often backed by lengthy manufacturer warranties

The Honest Decision Guide

Choose pressure-treated if: budget is the priority, you don’t mind periodic maintenance, or you love the look of real wood and plan to restain anyway.

Choose composite if: you want zero maintenance, plan to stay in the home long-term, or the deck gets full sun and hard use.

One More Option: Hybrid

Many of our favourite builds use PT framing with composite surface boards — you get structural lumber where it’s hidden and low-maintenance composite where your bare feet go. It’s often the best-value compromise.

Still torn? During a free estimate we walk both options against your actual yard and budget — reach out and we’ll bring samples.