Deck Construction near you

Most deck frames are pressure-treated lumber, whatever covers them, because joists and beams sit closest to moisture. The choice you notice is the decking and railing, each with its own balance of looks, upkeep and heat underfoot.

A deck footing has one job: to stay where it was put. Water in the soil turns to ice and expands, pushing up on anything anchored too close to the surface, so a footing that stops above the frost line can rise a little each winter until the deck tilts, the stairs pull away and the ledger strains against the house. The required depth depends on the building code in force and on your soil, and the permit drawings should show it.

Both methods below work when properly sized and installed; the choice mostly comes down to access, soil and schedule. The concrete contractors page covers pouring and curing.

An attached deck hangs one side of its frame on a ledger, a board fastened to the house's rim joist. It is a common point of failure and a frequent source of hidden damage. The builder fastens it with through-bolts or structural screws in the pattern the design calls for, into solid house framing rather than into siding, brick veneer or a thin trim board.

Water is the other risk. Rain and meltwater run down the wall and collect behind the ledger unless flashing sends them out over it. Without flashing, the rim joist and the ledger can rot out of sight, weakening the connection and letting moisture reach the basement or the floor structure.

Deck rules are set locally, and the height of the walking surface above the ground is usually what triggers a permit. In Toronto, a building permit is required to build a deck more than 60 centimetres (24 inches) above the ground. A lower, uncovered platform is exempt from the permit but must still comply with the zoning bylaw, and enclosing an existing deck of any size needs a permit.

Montreal handles permits by borough. Its page for Ahuntsic-Cartierville, for example, requires a permit to build or replace a deck, balcony, porch or front stoop whose floor is more than 60 centimetres above the ground, and for a floor higher than 1 metre it asks you to consult a plan designer and a borough representative before buying materials. The same page lists what to check first: distance from the lot lines, dimensions and floor height, guard height and baluster spacing, and the type of screen allowed.

Guards and stairs are safety items the building code governs in detail, from guard height and openings to steps and handrails; have the requirements for your deck's height shown on the drawings. A privacy screen may also fall under fence or zoning limits, which the fences page covers for Toronto.

Most of the planning happens before the first hole is dug. Zoning sets how close a deck may come to the lot lines and how much of the yard structures may cover, and the rules sometimes differ for a raised deck, a low platform and a privacy screen. A certificate of location in Quebec, or a survey in Ontario, shows where the lines are.

A deck is designed to carry snow as well as people, and the load depends on where you live, so the design follows your local code rather than a generic plan. Drifts build up against the house and snow sliding off a roof can land all at once, so keep the deck out from under the drip line where you can, and decide where shovelled snow will go. A hot tub adds its own weight on top of the snow, and the frame and footings must be designed for both.

New pressure-treated lumber is often too wet to take a finish right away, while cedar can usually be finished sooner; the product label explains how to test whether the wood is ready. A penetrating stain protects against sun and water better than a clear sealer and is easier to renew than a film-forming paint, which tends to peel on a horizontal surface. Composite, PVC and aluminum need only regular washing. The exterior painting page explains stain choices and surface preparation in more detail.