How much does it cost to install ductwork for a mini-split ducted system in the GTA?

Installing ductwork for a ducted mini-split system in a GTA home typically costs $2,000 to $6,000 for the duct portion alone, with the complete system (unit plus ductwork) running $5,000 to $12,000 depending on capacity, number of zones, and installation complexity. Ducted mini-splits are an increasingly popular choice in Toronto for additions, basement apartments, and homes without existing ductwork.

Unlike traditional ductless mini-splits with wall-mounted heads, ducted mini-split systems use a compact air handler concealed in a closet, ceiling space, or soffit that connects to a small network of ducts serving multiple rooms. The air handler is much smaller than a conventional furnace, which makes it ideal for tight spaces — a major advantage in Toronto's older homes where mechanical rooms are cramped or nonexistent. The refrigerant line still runs to an outdoor condenser, but the indoor distribution is entirely through ductwork, giving you the efficiency of a heat pump without visible wall units in every room.

The ductwork for these systems is typically smaller than conventional HVAC duct — most ducted mini-split air handlers use 6-inch or 8-inch round supply ducts rather than the 10-inch to 14-inch trunk lines of a furnace system. This makes routing through existing walls, ceilings, and soffits much easier. For a single-zone ducted mini-split serving two to four rooms in a basement apartment or addition, the ductwork portion usually costs $1,500 to $3,000, including supply runs, register boots, a small return, and all connections. A multi-zone system serving an entire floor or small home runs $3,000 to $6,000 for ductwork.

The total installed cost breaks down roughly as follows: the outdoor condenser unit runs $2,000 to $4,000 depending on capacity (typically 18,000 to 36,000 BTU for residential), the indoor air handler is $800 to $2,000, refrigerant line set and installation labour adds $1,000 to $2,500, and ductwork is the variable described above. Multi-zone systems with multiple indoor air handlers connected to a single outdoor unit cost more but eliminate the need for separate outdoor condensers.

In Toronto's post-war homes across Scarborough, North York, and Etobicoke, ducted mini-splits are a practical solution for adding air conditioning to second floors that were never connected to the original duct system. The compact ductwork can often be routed through closets and soffits without major structural work. For basement apartments — especially those requiring separate HVAC under Toronto's second suite regulations — a ducted mini-split with its own thermostat provides the independent climate control that building inspectors require.

Permits may be required depending on the scope of work. The electrical connection for the outdoor unit and air handler requires an ESA-licensed electrician, and if any gas disconnection is involved, a TSSA-registered contractor must handle that portion. Get multiple quotes from contractors experienced with ducted mini-split installations specifically — the duct design differs significantly from conventional forced-air systems. Toronto Ductwork can match you with local HVAC and ductwork professionals through the Toronto Construction Network.