Decks & Patios

A deck looks like a simple structure: joists, boards, railings, done. Yet ask any building envelope specialist in the Lower Mainland where houses rot, and decks will be near the head of the list. Not because decks themselves fail catastrophically, but because of the one detail where the deck meets the house. Get that connection wrong and the deck slowly destroys the wall it is attached to, invisibly, over years.

That is why it makes sense for a siding and envelope contractor to build decks. We spend our working lives managing water at wall penetrations, and a deck ledger is the largest, most heavily loaded penetration most houses will ever have. This page covers decking materials, railings, the flashing details that protect your home, membrane decks over living space, permits, and what maintenance really involves in this climate.

Wood Decking

Wood remains the traditional choice for good reasons: warm underfoot, easy to work, straightforward to repair board by board, and comfortable in summer heat where some synthetics get uncomfortably warm in full sun.

Species and Grades

Pressure treated lumber is the workhorse for framing and for budget conscious surfaces. Modern treatment is effective, but the boards are prone to checking and twisting as they dry, so a treated deck surface trades economy for appearance over time. Cedar is the regional favourite for visible surfaces, naturally decay resistant, dimensionally calm, and beautiful when maintained; its softness means furniture and dog claws leave their history in it. Imported hardwoods offer remarkable density and lifespan at a corresponding price and require dedicated fasteners and finishing practices.

Whatever the species, the framing details matter more than the decking: joist protection tape over every joist, correct fastener metallurgy for treated lumber, ventilation under low decks so the structure can dry, and end cuts sealed where boards were trimmed.

Finishing Wood Decks

Horizontal wood takes the full punishment of coastal weather, standing water, ultraviolet, foot traffic, and freeze cycles. Penetrating oils and semi transparent stains are the sensible finishes; film forming products on deck surfaces peel under traffic and become a stripping project. Expect renewal on a shorter cycle than any wall finish, and treat that honestly in the material decision, because it is the main ongoing cost of a wood surface. This is the same reasoning we walk through with cedar siding owners, compressed into a harsher exposure.

Composite and PVC Decking

Composite decking, wood fibre in a polymer matrix, and full PVC boards have matured enormously. Early generations faded, stained, and occasionally sagged. Current capped products carry a bonded polymer shell that resists fading and stains, come in convincing wood grain textures, and remove the sand and refinish cycle from ownership entirely: washing is the maintenance program.

The honest trade offs: purchase cost is meaningfully higher than treated lumber, dark colours get hot in direct summer sun, spans between joists are often shorter so framing can cost more, and thermal expansion along board lengths requires gapping discipline during installation. Composites also do not structurally reinforce anything; the frame beneath is still wood and still governs the deck's real lifespan. We build both wood and composite decks and the right answer usually falls out of three questions: how you use the space, how you feel about annual maintenance, and how long you plan to own the house.

Railings and Stairs

Railings are a life safety element with specific code requirements for height, opening sizes, and the loads a guard must resist, and they are checked during inspection for good reason. Options run from matching wood, to aluminum systems with minimal upkeep, to glass panels that preserve a view. Two field notes from experience: first, glass railings on exposed sites become a cleaning commitment their owners rarely anticipate; second, any wood post that penetrates a deck surface or sits unflashed against it is a rot starter, so post bases and connections deserve the same flashing thought as the structure itself. Stairs concentrate structural loads and foot traffic; stringer attachment and consistent riser heights are where amateur builds most often go wrong.

The Ledger: Where Decks Rot Houses

Now the detail that justifies this entire page. Most residential decks are attached to the house through a ledger board, a structural member bolted to the building that carries half the deck's load. To install it, the builder works directly against the wall, and here the paths split.

How It Goes Wrong

The shortcut installation bolts the ledger over or through the existing cladding, seals the intersection with caulking, and moves on. Water running down the wall face hits the ledger's upper edge, and caulking, which ages, cracks, and debonds, is the only thing keeping it out of the wall. Once through, water sits between ledger and sheathing, in wood to wood contact with no drying path, soaking the rim joist that holds up the floor of the house. This progresses for years with nothing visible outside. We have opened walls during siding replacement projects and found rim joists you could dig out with bare hands, all downstream of a ledger flashed with optimism.

The structural consequence is worse than rot alone: deck collapses, when they happen, are overwhelmingly ledger connection failures. A ledger bolted into decayed rim joist material holds until the day it does not, usually when the deck is full of people.

How It Goes Right

A correct ledger detail integrates with the wall's drainage layers, exactly like a window head. The cladding is opened, the weather resistive barrier is lapped and taped so it directs water outboard, metal flashing runs up behind the WRB and out over the ledger's upper edge with a drip leg that kicks water clear, and the fasteners hit solid, verified framing with proper corrosion resistant hardware. Where the house has a rainscreen, spacing details maintain the drainage cavity behind the ledger. Some situations justify going further with a freestanding deck on its own posts and beams, eliminating the wall penetration entirely, an option we raise whenever an existing wall's condition makes ledger attachment questionable.

This is envelope work, not carpentry alone. It is the reason deck building belongs in the hands of people who think about siding and walls for a living, and it is the first thing we inspect when asked to assess an existing deck.

Footings and Framing: The Part You Never See Again

Decking and railings get all the attention, but a deck's lifespan is written in its structure. Footings must reach below frost depth and bear on undisturbed soil, sized to the loads above them; in this region's wet clays and variable fills, guessing at bearing capacity is how decks develop a lean. Posts stand on standoff bases that keep end grain out of water, never buried in soil or set directly on concrete where they wick moisture continuously.

Above the posts, the quiet details compound: beams sized without optimism, joist hangers fully nailed with the correct fasteners rather than a few pan head screws, blocking that keeps long joists from rolling, and hardware rated for treated lumber, whose preservatives corrode ordinary zinc coatings surprisingly fast. Joist protection tape along every upper edge blocks the water that would otherwise sit in fastener holes, the primary way deck frames rot from within. None of this photographs well and all of it is invisible by the first barbecue, which is exactly why it is where careless builds economize. When we assess older decks, the framing and connections tell us more in ten minutes than the deck boards tell us in an hour.

Membrane Decks Over Living Space

Some decks are also roofs: a walkable surface over a room below, a sundeck above a garage, a rooftop patio. These assemblies raise the stakes because any leak lands directly in finished space. At a general level, they work by making the structural surface waterproof with a continuous membrane, vinyl sheet systems and liquid applied membranes being common, sloped to drain, with every edge, post, and door threshold detailed into the waterproofing. The membrane is the roof; tiles or sleeper supported boards above it are just wear surface.

Two principles cover most of what an owner needs to know. First, penetrations and perimeters cause nearly all failures, not the field of the membrane, which is why railing attachments on membrane decks should be engineered into the detail rather than screwed through it afterward. Second, the door from the house onto such a deck is a critical junction where the membrane, the wall's WRB, and the door's sill pan must all connect; we cover that logic from the wall side in our windows and doors service. Because this surface functions as a roof, scope boundaries matter: we build and detail deck structures and their wall integration, and we coordinate with membrane specialists where a project calls for them.

Patios and Grade Level Outdoor Structures

Not every outdoor space needs to be elevated. Grade level patios, concrete, pavers, or stone, avoid ledgers and railings entirely and suit many yards better. The construction discipline shifts to ground preparation and drainage: compacted base, slope away from the building, and surface elevations kept sensibly below interior floor level and clear of the cladding's lower edge so splash and ponding do not attack the wall base. Pergolas, privacy screens, and covered outdoor areas follow the same rule as everything else on this page: wherever they touch the house, the connection gets flashed like it matters, because it does. A post or beam tied casually into a wall is a future water damage restoration file.

Permits and Inspections

Municipalities across the Lower Mainland require permits for decks above modest heights or sizes, and for any deck over living space; exact thresholds vary by city, so it is worth confirming locally rather than assuming. The permit process typically reviews structure, guard details, and setbacks, with inspections at framing stages. Skipping permits invites real costs later: insurance complications after any incident, forced alterations discovered at sale time, and no inspection backstop on a structure your family stands on. We handle permit drawings and applications as part of the project so the process costs you attention only where your preferences are needed.

Maintenance in This Climate

Every deck here lives under falling needles and eight months of moisture. The annual rhythm that keeps them healthy is simple: clear debris from board gaps so water drains, wash off algae before it becomes a slip hazard, check that flashings are intact and that soil or planters have not crept up against the house wall, and probe railings and stair connections for movement. Wood surfaces add finish renewal on their own cycle. Ten minutes with a flashlight under the deck each spring, looking for staining at the ledger and corrosion at hangers, is the cheapest structural inspection you will ever perform.

Build It Once, Build It Right

Berkana Construction Management builds decks and outdoor structures across the Lower Mainland with the same envelope discipline we bring to every wall, from our base at 13490 224th St in Maple Ridge. Licensed, insured, and WorkSafeBC compliant since 2019, we start every project with a free written quote. If you are planning a new deck, or wondering what an existing one is doing to your house, call (672) 771-6868 and we will come take a look.