What is the price difference between galvanized steel and aluminum ductwork in the GTA?

Aluminum ductwork costs roughly 40 to 60% more than galvanized steel in the GTA market, with aluminum running $12 to $28 per linear foot installed compared to $8 to $20 per linear foot for standard galvanized steel round duct. For a complete residential duct system with 200 linear feet of ductwork, that premium translates to an additional $1,500 to $3,000 on the total project — a significant difference that rarely justifies itself in a typical Toronto home.

Galvanized steel is the industry standard for residential ductwork in the GTA for good reasons. It is durable, fire-resistant, provides a smooth interior surface for low air friction, and does not support mould growth. Galvanized steel holds up well in Toronto's climate extremes — the zinc coating provides excellent corrosion resistance even through decades of condensation exposure in basements and temperature cycling through our freeze-thaw winters. The vast majority of GTA ductwork contractors stock galvanized steel fittings and work with it daily, meaning fabrication is faster and labour costs are lower.

Aluminum duct has specific advantages, but they rarely apply to typical residential installations. Aluminum is about one-third the weight of steel, making it easier to handle in tight spaces and reducing load on hangers and supports. It is naturally corrosion-resistant without a coating, making it the preferred choice in marine environments, coastal areas, or high-humidity commercial applications like swimming pool buildings. Aluminum also does not spark, which matters in certain industrial settings. However, none of these advantages are particularly relevant to a typical GTA home.

Where aluminum does see legitimate residential use in Toronto is for dryer vent ducts and certain exhaust applications. Rigid aluminum dryer vent duct is actually the recommended material for dryer venting — it is smooth, corrosion-resistant, and handles the heat and moisture from dryer exhaust better than other options. A rigid aluminum dryer vent installation runs $200 to $600 in the GTA, and the material choice is well justified here.

One practical consideration is contractor availability. Because aluminum ductwork is uncommon in GTA residential work, fewer contractors carry aluminum fittings in stock. Custom aluminum fabrication takes longer and costs more, and not all sheet metal shops are set up to work with aluminum (it requires different joining techniques than steel). This limited availability contributes to the price premium and can extend project timelines.

For the vast majority of Toronto homeowners, galvanized steel is the right choice. It delivers excellent performance at a lower cost, every GTA ductwork contractor is experienced with it, and replacement fittings are readily available for future modifications. Save your renovation budget for upgrades that deliver measurable comfort improvements — like proper duct sealing with mastic, adequate return air ducts, or R-8 insulation on any runs through unconditioned spaces.

Need help comparing quotes for your ductwork project? Toronto Ductwork can match you with local contractors through the Toronto Construction Network for free.