How to Save on Deck Building in London (August 2026 Real Cost Data)

If you are looking at your backyard in Old North or Wortley Village and imagining a space for summer hosting, you are likely calculating the return on investment for a new deck. In the London market right now, a well-built outdoor space is one of the smartest ways to boost property value. However, you need to be prepared for the price tag. The average deck building cost in London is $22,602 CAD this August. While you can get a basic platform started for around $8,000, high-end composite builds with multi-level features can easily climb to $75,000. With costs up 9.9% over last year, London homeowners are paying a premium for quality outdoor living space.

How Much Does Deck Building Cost in London?

When you look at the numbers, that $22,602 average covers a wide variety of projects. For an investor looking to maximize rental yield in a student-heavy area like near Western University, a simple pressure-treated wood deck is the standard. These entry-level projects typically land in the $8,000 to $15,000 range. They provide the necessary square footage without the bells and whistles.

If you are aiming for a mid-range build, expect to spend between $20,000 and $35,000. This usually gets you a larger footprint, perhaps using cedar or a mix of pressure-treated framing with composite decking boards. At the top end, the $75,000 projects usually involve custom lighting, built-in outdoor kitchens, and premium materials like Ipe or top-tier Trex. These high-end decks are becoming more common in newer developments in Byron or Sunningdale, where homeowners view the deck as a full extension of the home's square footage.

What Affects the Cost?

Several factors drive your final invoice in the Forest City. First is the material choice. Pressure-treated lumber is the most affordable, but in London's humid summers and freezing winters, it requires significant maintenance. Composite materials cost more upfront but offer a better long-term ROI because they don't rot or warp.

The London labor market is another major factor. We are seeing a shortage of skilled carpenters right now, which has pushed hourly rates higher across Southwestern Ontario. If you want a reputable crew, you are paying for their expertise and their insurance.

Permits and inspections also add to the tally. In London, any deck over 24 inches above the finished grade requires a building permit. The City of London Building Division bases fees on the value of the work, and you'll need to account for the time it takes to get those drawings approved.

Finally, the physical site matters. If your backyard in a neighborhood like Oakridge has a significant slope or requires clearing out old silver maple roots, your footings will be more expensive. Helical piles are becoming a popular, albeit pricier, alternative to traditional concrete sonotubes in London because they can be installed quickly even if the ground is stubborn.

How London Compares to Other Canadian Cities

London is currently sitting on the higher end of the spectrum for Southwestern Ontario. Our average of $22,602 is noticeably higher than our neighbors in Windsor, where the average cost is $19,333. This is largely due to the higher property values in London and a tighter labor market for specialized deck builders.

When you look further east, London is more expensive than Oshawa, which sits at an average of $21,045. Interestingly, we are nearly double the cost of Barrie, where the average is just $13,424. This discrepancy often comes down to the types of decks being built; Londoners are currently trending toward more permanent, high-finish outdoor rooms rather than simple utility decks. Compared to the East Coast, London is slightly more expensive than St. John's, which averages $22,115, despite the logistical challenges of island construction.

How to Save Money on Deck Building

If you want to keep costs closer to that $8,000 floor, timing is everything. Most people start calling contractors in May when the first warm Saturday hits. By then, the best crews are booked through September. To save money, try to book your project for the "shoulder seasons." Late August or early September is a great time to start. The ground is dry, which makes digging footings easier, and contractors are often looking to fill their fall schedules before the snow flies.

Another way to save is by handling the demolition yourself. If you have an old, rotting deck, taking it apart and hauling the debris to the EnviroDepot on Clarke Road can save you a few thousand dollars in labor and disposal fees.

Focus on the "bones" of the deck first. You can build a high-quality structure now and add the expensive glass railings or the built-in LED lighting systems in a year or two. This spreads out the financial hit while still giving you a functional space for this season. Also, stick to a simple rectangular design. Every extra corner or "bump out" adds significant waste in material and hours in labor.

Is 2026 a Good Time for Deck Building in London?

The 9.9% year-over-year increase is a bit of a sting, but there is no sign that prices will drop in 2027. If you are waiting for a massive correction in material costs, you might be waiting a long time. Right now, the London real estate market remains resilient, and an outdoor renovation is one of the few projects where you can recoup a large portion of the cost upon resale.

From an investor's perspective, the "cost-per-year-of-use" is the metric that matters. Starting your project now means you get the full use of the space for the upcoming autumn - which is arguably the best deck weather in London anyway. If you have the budget, get your quotes now. The best contractors in town are already looking at their late 2026 and early 2027 calendars.

FAQ

How long does deck building take in London?

A standard 12x16 deck usually takes about 3 to 5 days of actual construction time. However, you need to factor in the 2 to 4 weeks for the City of London to process your permit and the time required for the concrete footings to cure if you aren't using helical piles.

Do I need a permit for deck building in London?

Yes, if the deck is more than 24 inches (0.6 meters) above the ground or if it is attached to the house. Even if it is lower than 24 inches but has a roof or is over a certain size, you likely need to visit the building department at 300 Dufferin Ave to file paperwork.

What is the best material for London's climate?

Composite is the winner for longevity. London experiences extreme temperature swings. Wood expands and contracts significantly here, leading to cracks and splinters. Composite handles the freeze-thaw cycles of January and the humidity of August much better with almost zero maintenance.

Check the latest deck building costs for London and other cities on LookupCost.com.