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Cedar vs Composite vs Pressure-Treated Decking in Ontario

Compare cedar, composite, PVC, and pressure-treated decking for an Ontario home, including care, heat, framing, gaps, fasteners, and quote details.

  • 5 min read
  • by Sawdust & Steel Workshop
Cedar deck with a built-in bench in an Ontario backyard

Think about the deck on an ordinary afternoon: bare feet, full sun, food spills, and whatever time you have for upkeep. Cedar, composite, PVC, and pressure-treated wood suit different priorities. Compare samples outdoors, then price your preferred boards on the same complete deck design.

Which decking material fits your priorities?

DecisionCedarComposite or PVCPressure-treated
Best fitNatural appearance and finish choiceLess refinishing and consistent colourLower initial surface-material cost
Routine careCleaning plus finish inspectionCleaning with approved productsCleaning, drying, and finish inspection
Installation variableGrade, moisture, gaps, and corrosion-resistant fastenersExact line, temperature, layout, gaps, clips, and supportTreatment type, moisture, end cuts, and compatible fasteners
Check before buyingFull-size board after wetting and sun exposureHeat, traction, sheen, warranty, and local availabilityBoard straightness, grade, treatment label, and drying plan
A decision guide, not a substitute for the selected product's instructions.

What do you gain and give up with cedar?

Western red cedar gives you a real wood surface that can be finished or allowed to weather naturally. It also asks you to pay attention to grade, moisture, sun, drainage, and the finish manufacturer's recoat signals. A universal stain it every two years rule is too tidy for different exposures and products. Inspect the surface and follow the selected finish instructions; our new-deck staining guide explains why moisture matters more than the calendar.

The Western Red Cedar Lumber Association's fastener guidance recommends corrosion-resistant fasteners and warns against products that can corrode or stain cedar. Fastener grade is not an aesthetic upgrade. It must suit the wood, connector, exposure, and approved detail.

Multi-level cedar deck with a stone patio and firepit in an Ontario backyard at sunset
Cedar can be finished to retain colour or allowed to weather. The care plan should be chosen before installation.

What changes when you choose composite or PVC?

Composite and PVC are families of products, not one interchangeable board. The exact collection controls maximum joist spacing, diagonal-layout support, end and side gaps, stair-tread framing, approved fasteners, overhangs, ventilation, and warranty coverage. TimberTech's current installation guides and Trex's joist-spacing guidance both send the installer back to the selected product and layout. Check these details before the frame is built.

Colour and exposure matter too. Every outdoor surface can become hot in direct sun, and a small indoor sample will not tell you how a dark board feels on a south-facing deck. Put full-size samples outside, wet them, walk on them with the footwear your household uses, and check them again in afternoon sun. Less refinishing does not mean no care: Trex and TimberTech publish different Trex care instructions and TimberTech cleaning limits for their products.

Grey composite deck with a cedar pergola and a grill station
Board colour, exposure, layout, and the exact product line all affect the finished surface and its framing requirements.

When does pressure-treated decking make sense?

Pressure-treated decking is useful when the initial surface-material budget matters and a natural wood appearance is acceptable. The treatment label, use category, lumber grade, moisture at installation, end-cut treatment, fasteners, and finish plan still need to be specified. Wet boards can shrink as they dry, so a fixed gap copied from another project is not a specification.

Wood Preservation Canada says exposed cuts and holes should receive an appropriate registered end-cut preservative and that hardware must be compatible with the preservative and intended exposure. Its deck-board fastening tips also call for exterior fasteners approved for treated wood. Match the hardware to both the treatment and the connector specification.

Does the decking choice change the frame?

Often, yes. Board thickness, direction, picture framing, stair layout, concentrated loads, and hidden-fastener systems can change joist spacing and blocking. The City of Mississauga's current deck drawing requirements require the framing plan to show member size, type, grade, spacing, spans, piers, beams, and posts. The approved drawing and selected board instructions should agree before material is ordered.

Long composite deck overlooking a garden view
Long runs, borders, stairs, and diagonal patterns need product-specific support and expansion details.

What should the decking quote specify?

  • Exact manufacturer, collection, profile, colour, board dimensions, and quantity allowance.
  • For wood, species, grade, treatment label where applicable, moisture condition, and finish system.
  • Joist spacing, blocking, borders, stairs, ventilation, gaps, and overhangs tied to the approved drawing and product instructions.
  • Fastener and connector manufacturer, model, material, coating, and visible or hidden layout.
  • Treatment of cut ends, exposed framing, ledger water management, and board-end details.
  • Cleaning, finish, warranty-registration, and replacement-board information handed over at completion.

Choose the surface after the house, exposure, maintenance tolerance, and complete installed scope are clear. Then price that exact specification using the GTA deck-cost guide. Ask for the exact product line beside any composite allowance so you can compare like for like.

questions & answers

Things homeowners ask.

  • Which deck material usually has the lowest initial cost?

    Pressure-treated decking commonly has the lowest initial board cost, but compare the same foundations, frame, stairs, guards, fasteners, finish, demolition, permits, and tax. A cheaper surface allowance does not make an incomplete structural quote cheaper overall.

  • Does composite decking always require joists at 12 inches on centre?

    No. Maximum spacing depends on the exact manufacturer, product line, board profile, residential or commercial use, board direction, stair application, and layout. Follow the current product instructions and the approved framing plan rather than a universal number.

  • How often should an Ontario cedar deck be stained?

    There is no reliable universal interval. Exposure, board condition, preparation, finish type, colour, drainage, and use all matter. Inspect the surface and refinish when the selected product calls for it; check that the wood is dry enough before recoating.