Side-by-side honest comparison of cost, lifespan, and maintenance — based on what we've seen on real GTA decks after 5+ winters.
Every deck consultation we do starts with the same question: composite or pressure-treated? Both have their place, but the right answer depends entirely on how you plan to live with the deck for the next 15–20 years.
Pressure-treated lumber is the value option. You're looking at roughly 40–50% lower material cost upfront, and a properly built PT deck will last 15–20 years in Toronto's climate. The catch: you'll need to stain or seal it every 2–3 years, and even then the boards will show their age.
Composite (Trex, TimberTech, etc.) costs more upfront but the math changes over 10 years. Zero staining, no splinters, and the boards we installed in 2018 still look essentially new. For families with kids or anyone who just doesn't want a maintenance hobby, composite usually wins.
One thing we never compromise on either way: the substructure. Pressure-treated joists, galvanized hardware, properly set footings below frost line. The deck surface is what you see — the framing is what keeps it standing for two decades.
