There is no single right answer. Each material has genuine strengths and genuine trade-offs. This guide walks through both so you can make an informed decision, or talk it through with a contractor who knows what works in this climate. If you are also planning a pool, pergola, or outdoor kitchen alongside your deck, see our custom deck installation page for more on how we approach full backyard projects in Toronto and South Mississauga.
What Is Pressure Treated Wood?
Pressure treated lumber is wood that has been infused with chemical preservatives under pressure to resist rot, insects, and moisture. It has been the standard choice for deck framing and decking boards across Canada for decades, and for good reason: it is widely available, cost-effective, and relatively straightforward to work with on site.
In Ontario, pressure treated wood is commonly made from local species treated to meet Canadian Standards Association specifications. It can be stained or painted to achieve a range of looks, and it is easy to cut and install with standard tools. The natural look and feel of real wood is something many homeowners genuinely prefer.
What Is Composite Decking?
Composite decking is an engineered product made from a blend of wood fibre and recycled plastic, bound together with resins and UV stabilizers. Manufacturers developed it specifically to address the weaknesses of natural wood: moisture absorption, rot, fading, and splitting.
Composite boards come in a wide range of colours, textures, and finishes, including options that closely mimic the grain of natural wood. Most quality composite products carry long manufacturer warranties and are designed to hold their appearance with minimal upkeep year over year.
How Toronto’s Climate Affects Your Deck
Toronto’s climate is genuinely tough on outdoor materials. Winters bring repeated freeze-thaw cycles, where temperatures climb above zero during the day and drop below at night. This repeated expansion and contraction is one of the main reasons wood decks can crack, warp, and split over time without proper sealing.
Spring brings snowmelt and extended periods of surface moisture. Summer brings high humidity and intense UV exposure. Any decking material you choose has to handle all of these conditions reliably, year after year.
Pressure treated wood absorbs moisture and expands and contracts with temperature changes. Over time, this can lead to cupping, cracking, and surface checking, especially if the deck is not properly sealed each season. Composite decking is engineered to resist moisture absorption and is less affected by freeze-thaw cycling, which is one of the main reasons it has grown in popularity in Ontario over the past decade.
Composite vs Pressure Treated: Side-by-Side Comparison
| Factor | Pressure Treated Wood | Composite Decking |
|---|---|---|
| Upfront Cost | Lower | Higher |
| Long-Term Maintenance | Annual sealing and staining required | Minimal, periodic washing only |
| Freeze-Thaw Resistance | Moderate; can crack or warp over time | High; engineered to resist moisture cycling |
| Rot and Insect Resistance | Good with treatment; declines without upkeep | Excellent; no organic material to decay |
| Appearance Over Time | Fades and greys without regular staining | Holds colour well; minor fading possible |
| Summer Heat Retention | Stays relatively cool underfoot | Can become warm; darker colours more so |
| Repairability | Individual boards easy to replace or sand | Full board replacement required if damaged |
| Typical Lifespan (with care) | 15 to 20+ years | 25 to 50 years depending on product grade |
| Environmental Profile | Natural material; chemical preservatives used | Often made with recycled content |
Maintenance: What Each Material Asks of You
This is where the two options diverge most sharply, and it is worth thinking honestly about how much time and money you want to put into upkeep over the years.
Pressure treated wood needs to be sealed and stained regularly, typically once a year or every two years depending on sun and rain exposure. If you skip this, the wood will begin to grey, then crack, then eventually rot at the surface. It also needs to be inspected each spring for boards that have shifted, split, or lifted over the winter. On the positive side, individual boards are inexpensive and easy to replace, and light sanding can often restore minor surface damage without replacing the board entirely.
Composite decking largely takes care of itself. Washing it down with soap and water once or twice a year is usually all the maintenance required. There is no staining, sealing, or sanding involved. The trade-off is that composite boards cannot be refinished if they are scratched or gouged. Because the colour runs only through the outer layer on some product lines, deep scratches can be more visible than on stained wood.
Is Composite or Pressure Treated Better for Pool Decks?
If your deck will sit adjacent to a swimming pool or hot tub, moisture resistance becomes especially important. Pool decks face constant splashing, chemical runoff from pool water, and wet foot traffic that would accelerate deterioration in unsealed wood.
Many Toronto homeowners building pools opt for composite decking around the pool surround specifically because of its water resistance and because it will not splinter underfoot when wet. That said, the final choice depends on the overall design, the rest of the backyard layout, and personal preference. Some homeowners pair a pressure treated frame with composite boards to get the structural benefits of wood with the surface performance of composite.
For anyone thinking about the full backyard picture, combining a new deck with a pool, outdoor kitchen, or landscaping, planning all the elements together from the start leads to better results. See our inground swimming pool installation page and our outdoor kitchen installation services to see how these pieces come together in a complete backyard design.
Which Option Fits Your Budget and Goals?
Pressure treated wood has a lower upfront cost, which can matter when you are managing a broader backyard renovation budget. It is a proven material that countless Toronto homeowners have used successfully for generations. It is also easier to repair and modify down the road if your needs change.
Composite decking costs more to install but significantly less to maintain over the long run. If you plan to stay in your home for many years and want to reduce the ongoing time and cost of seasonal upkeep, composite often works out to be the better investment when viewed across the full lifespan of the deck.
Both materials can produce a beautiful, functional deck. The right choice depends on your budget, how hands-on you want to be with maintenance, and the look you are working toward. Explore our backyard landscaping ideas for inspiration on how a new deck fits into a complete outdoor living space.
Frequently Asked Questions
How long does composite decking last in Toronto?
Quality composite decking products typically carry warranties ranging from 25 to 50 years. In Toronto’s climate, with proper installation and basic cleaning, composite decking can realistically last several decades with minimal maintenance required.
Does pressure treated wood hold up in Ontario winters?
Pressure treated wood can hold up well in Ontario winters when properly maintained. The key is keeping it sealed and stained to protect against moisture absorption. Without regular upkeep, repeated freeze-thaw cycles will cause it to crack and warp over time.
Which decking material requires less maintenance?
Composite decking requires significantly less maintenance than pressure treated wood. It does not need annual staining or sealing and can be kept clean with a simple wash. Pressure treated wood needs to be resealed and stained regularly to maintain its appearance and structural integrity.
Can I install composite decking over an existing pressure treated frame?
Yes, in many cases composite deck boards can be installed over an existing structural frame, provided the frame is in good condition and meets the spacing requirements for the composite product. Your contractor will assess the existing framing before proceeding.
Is composite decking slippery when wet?
Most modern composite decking products are manufactured with a textured surface designed to provide grip when wet. This makes composite a practical choice for pool decks and other areas exposed to frequent water, though the specific texture varies by product and brand.
Plan Your Toronto Deck with Destination Pools
Choosing the right decking material is just one part of building a backyard you will enjoy for years. At Destination Pools and Landscaping, we design and build custom decks throughout Toronto and South Mississauga, and we can help you weigh all the material, layout, and design options for your specific property and lifestyle.
Contact us today to start planning your project. Whether you are building a standalone deck or a complete outdoor transformation with a pool, kitchen, and landscaping, we would love to help bring the vision to life.
