Can I use smaller high-velocity ducts instead of standard ductwork in my Toronto home?

Yes, high-velocity duct systems are a legitimate alternative to conventional ductwork, and they are particularly well-suited to older Toronto homes where installing standard-size ducts would be impractical or destructive. Systems like SpacePak and Unico use small-diameter flexible tubing — typically 2 to 3 inches — instead of the 6 to 14-inch ducts used in conventional systems, delivering conditioned air at higher velocities through small, unobtrusive outlets.

The main advantage of high-velocity systems in the GTA context is their ability to retrofit heating and cooling into homes that were never designed for ductwork. Many pre-war homes in established Toronto neighbourhoods like the Annex, Roncesvalles, Leslieville, and Riverdale use hot water radiators or steam heat with no existing duct system. Installing conventional ductwork in these homes would require extensive demolition — opening walls, dropping ceilings, and building soffits that compromise the architectural character. High-velocity tubing can be snaked through wall cavities, between floor joists, and through closets with minimal disruption, often requiring only 3-inch holes rather than the large chases needed for standard ducts. The small round outlets sit nearly flush with walls or ceilings and are far less visually intrusive than conventional registers.

The trade-offs are important to understand. High-velocity systems cost significantly more than conventional ductwork — expect $12,000 to $25,000 fully installed for a typical 1,500 to 2,500 square foot Toronto home, compared to $5,000 to $15,000 for a conventional system. The air handler units are specialized and not interchangeable with standard furnaces, so you are committing to a specific equipment ecosystem. Operating noise can be higher than conventional systems, particularly near the air handler and at outlets that are not properly installed — though modern high-velocity systems have improved dramatically and many homeowners find the gentle white noise acceptable. Energy efficiency is comparable to conventional systems when properly designed, but the higher air velocities mean the system is more sensitive to installation quality.

High-velocity systems work best in specific situations: homes with no existing ductwork, heritage properties where preserving original plaster walls and trim is essential, additions where running conventional ducts from the existing system is impractical, and condos or multi-unit buildings where space constraints rule out standard ducts. They are generally not the best choice for new construction or homes with existing conventional ductwork in good condition — in those cases, a properly designed conventional system delivers the same comfort at lower cost.

If you are considering a high-velocity system, look for contractors who specialize in these installations — not every HVAC company has experience with SpacePak or Unico, and installation quality is critical. The system design requires careful calculation of air volumes and outlet placement to ensure even comfort throughout the home. Toronto Ductwork can help you find contractors experienced with high-velocity installations in the GTA.