What is the average price to replace all ductwork in a 1,500 square foot GTA bungalow?

A complete duct replacement in a 1,500 square foot GTA bungalow typically costs $5,000 to $12,000, including removal and disposal of the old ductwork, installation of the new system, sealing, and basic insulation. Bungalows are generally the most straightforward duct replacement because all runs are accessible from the basement — there are no interior wall chases or upper-floor routing to complicate the job.

The wide price range reflects real variables that affect every project. A post-war bungalow in Scarborough or Etobicoke with a simple rectangular trunk line and eight to twelve supply branches will land closer to $5,000 to $7,000 if the layout is straightforward and the basement is unfinished. A larger bungalow with a finished basement, multiple returns, longer branch runs, and the need to work around existing finishes will push toward $8,000 to $12,000. If the existing ductwork contains asbestos tape or insulation — common in homes built between the 1940s and 1970s — professional abatement adds $2,000 to $5,000 on top of the replacement cost. Always have the old ductwork tested before any demolition begins.

Why replace rather than repair? Many post-war GTA bungalows have original galvanized steel ductwork that is now 50 to 70 years old. These systems were designed for heating only — when central air conditioning was added later, the existing ducts were often undersized for cooling loads. Cooling requires approximately 400 CFM per ton compared to 300 CFM per ton for heating, so a duct system that worked adequately for a furnace may deliver inadequate airflow for air conditioning. Common symptoms include rooms that never cool properly in summer, excessive noise from high air velocity through undersized ducts, and a single undersized return grille on the main floor that starves the system of air.

A proper replacement addresses all of these issues. Your contractor should perform Manual D duct design calculations to size every trunk line, branch, and return correctly for both heating and cooling. The new system should include dedicated return air ducts from bedrooms and the basement — not just a single central return. All joints should be sealed with duct mastic and UL 181 foil tape, and any runs through unconditioned spaces need R-8 insulation minimum.

For a typical bungalow replacement, expect the work to take two to three days with a crew of two or three installers. Budget $200 to $500 for the City of Toronto mechanical permit. When getting quotes, ask specifically whether the contractor includes new register boots, supply and return grilles, dampers for balancing, and proper mastic sealing — some quotes exclude these items and add them as extras later.

Need help finding a ductwork contractor for your bungalow? Toronto Ductwork can match you with local professionals for free estimates through the Toronto Construction Network.