How Much Does It Cost to Build a Deck in London, Ontario? (2025)

Decks · 5 min read

A deck is one of the best-value upgrades you can make to a London, Ontario home — it adds usable living space and real resale appeal. But what should you expect to pay in 2025? Deck pricing varies widely with size, materials and complexity, so here's a clear breakdown to help you budget.

Priced by Size and Material

Most decks are quoted by square footage, and the material you choose sets the baseline. Pressure-treated lumber is the most budget-friendly and remains the most common choice in London. Cedar costs more for its natural beauty and rot resistance, and composite sits at the top for its near-zero maintenance. A small ground-level platform is far less than a large, elevated, multi-level deck — height and structure drive both material and labour.

What Adds to the Cost

Beyond size and decking material, the big cost drivers are height (elevated decks need more substructure, stairs and railings), railings (a significant line item, especially glass or aluminum), footings (proper piers below the frost line are essential in our climate and non-negotiable for a deck that won't heave), and features like built-in benches, privacy screens, pergolas or wrap-around stairs. Site access and removal of an old deck also factor in.

Don't Forget the Permit

Many decks in London require a building permit, particularly those above a certain height off the ground or attached to the house. Permit and inspection requirements exist for safety — they make sure the structure, footings and railings meet code. Skipping a required permit can cause problems at resale, so we factor this into planning rather than treating it as an afterthought.

Where the Value Is

The cheapest deck quote often means undersized footings or thin materials that show their age within a few winters. We build on solid, frost-depth footings with quality lumber and clean detailing, and back it with a 2-year workmanship warranty. If you're still deciding on boards, our guide to wood vs. composite decking compares lifetime cost, and you can see our full process on the deck building page. The only way to a real number is a free on-site quote — every yard and design is different.