🪵 Decks & Porches: what it costs in the GTA (2026)

In most GTA municipalities, a deck more than 24 inches off grade needs a permit, engineered guards, and inspected footings. This is genuinely good: the failures you read about are almost always unpermitted decks pulling away from houses at the ledger board. A proper contractor handles the drawings and the permit desk. If a quote's price depends on skipping the permit, you're being asked to hold someone else's risk.

GTA frost reaches about 4 feet down, so footings must too. Deck blocks sitting on grade ride the frost like a boat: up in January, down (unevenly) in April. That's the wavy, drunk-uncle deck you've seen. Sonotubes to below frost line, sized to the load, are non-negotiable for anything attached to a house. For low floating decks, helical piles have become the smart-money option: installed in a day, no concrete cure, removable.

PT lumber costs roughly half up front and wants staining every 2–3 years; skip it and boards check, cup, and grey. Composite costs more on day one, then asks for soap and water, ever. Over ten years, an honestly maintained PT deck plus stain weekends often lands within shouting distance of composite money. Buy PT if you'll actually maintain it or love the wood look; buy composite if your weekends are worth more than the delta.

Ledger connection (where deck meets house): needs proper flashing and structural fasteners, not deck screws; this is the failure that drops decks. Guardrails: should take a hard shove without a wiggle; more than a quarter inch of movement is a fix-now item. Stair stringers: rot at the bottom cut where they meet concrete. Joist tops: water sits under boards; joist tape at build time adds years for pennies. We look at all four before quoting anything.