Decks

The order that saves money

1. Find out whether you need a permit — and what triggers it. Most Canadian municipalities require a permit above a threshold set by deck height, area, or attachment to the house, and the thresholds vary. A deck built without a required permit is a problem at resale, an insurance question after any incident, and occasionally an order to remove. Ask before you build, not after.

2. Settle the foundation, because frost decides it. This is where most deck budgets and most deck failures originate. Footings have to bear below your local frost depth, and frost depth varies dramatically across the country. A footing that stops short will lift and drop seasonally, taking the deck's geometry — and the ledger connection to your house — with it. Deck blocks sitting on grade are acceptable for some low freestanding platforms and unacceptable for anything attached to a house.

3. Decide attached or freestanding. This is a bigger decision than it looks. Attaching to the house saves a beam line and a row of footings but introduces the ledger — a connection that must be structurally fastened and properly flashed. Improperly flashed ledgers rot the house's rim joist from the inside, and ledger failure is the leading cause of deck collapses. A freestanding deck costs more in footings and avoids the problem entirely.

4. Height drives more than you'd think. Two decks with the same area at different heights aren't comparable: taller posts, deeper footings, bracing, more stair steps, and past a code threshold, mandatory guards. Railings cost far more per foot than decking does, so height and perimeter shape can move the total substantially.

5. Choose the decking surface last. It's the most visible decision and the least structural one. Pressure-treated, cedar, composite, and PVC span a wide price range, and the honest comparison is cost over the years you'll own it — including the weekend each spring that PT and cedar demand and composite doesn't.

Where deck budgets go wrong

• Treating the foundation as an afterthought. It's the one part you can't fix later without dismantling everything above it, and it's the part frost attacks every single winter.
• Under-budgeting railings. They cost more per linear foot than the deck surface costs per square foot, and long narrow decks have disproportionately more perimeter.
• Improvising the ledger. Structural fasteners and proper flashing are not the place to economize or eyeball. This is the detail most worth reading about before you start.
• Forgetting to call for utility locates before augering a dozen deep holes. Free in most of Canada, mandatory, and skipping it risks striking gas or hydro.
• Adding a hot tub later. A standard deck isn't designed for the load. Retrofitting means additional footings and framing — decide before you build.
• Comparing a DIY materials list to a contractor's installed quote. Labour is roughly 40–50% of a built deck. Both numbers are valid; they just aren't the same number.

Decks are among the most approachable structures to build yourself — provided the footings go deep enough and the ledger is done properly. Those two details carry most of the risk.