What is the price to install a kitchen exhaust duct with a roof cap in a Toronto townhouse?

Installing a kitchen exhaust duct with a roof cap in a Toronto townhouse typically costs $800–$2,500, with most projects landing in the $1,200–$1,800 range depending on run length, duct routing, and whether the hood is already in place.

The wide price range comes down to a few key variables. The most important is the distance from your range hood to the exterior termination point — a short 6-foot run through an exterior wall costs far less than a 15-foot run up through a second-floor ceiling and out the roof. Townhouses in Toronto add their own complexity: party walls on both sides often eliminate the option of a simple side-wall exit, and many GTA townhouses have finished ceilings on every floor, meaning the duct has to be concealed inside a bulkhead or chased through a wall cavity rather than run exposed through an unfinished basement. That extra framing and drywall work adds $300–$600 to the ductwork cost alone, before you factor in any finishing trades.

The roof cap itself is a meaningful cost item. A quality stainless steel or galvanized roof cap with a backdraft damper runs $80–$200 in material, and the labour to safely work on a townhouse roof — setting up proper fall protection, cutting the penetration, flashing and sealing the cap against the GTA's freeze-thaw cycles — typically adds $300–$500 in labour. A roof cap that isn't properly flashed will leak within a few winters. This is not a place to cut corners, especially given Toronto's ice storm and heavy snow load conditions.

Duct Material Matters

For kitchen exhaust, rigid aluminum or galvanized steel duct is the only acceptable choice — grease-laden air from cooking requires smooth, cleanable interior surfaces and fire-resistant materials. Flex duct is never appropriate for kitchen exhaust. The Ontario Building Code and NFPA 96 both require smooth-wall rigid duct for range hood exhaust. The duct should be as straight as possible with minimal elbows — each 90-degree elbow is equivalent to adding 10–15 feet of duct length in terms of airflow resistance, and a hood that can't move air efficiently defeats the purpose entirely.

The Make-Up Air Question

This is where many Toronto townhouse projects get more expensive than homeowners expect. If your range hood moves more than approximately 400 CFM (roughly 190 litres per second), Ontario Building Code Part 6 requires a make-up air system to replace the air being exhausted. In a tightly built modern townhouse, running a 600 or 900 CFM hood without make-up air creates negative pressure that can backdraft gas appliances — a carbon monoxide risk. A make-up air system adds $2,000–$5,000 to the project and must be interlocked with the hood so it activates automatically. If your hood is 400 CFM or under, you are generally below the threshold, but confirm with your contractor.

Permits and Trades to Coordinate

A new kitchen exhaust duct installation in Toronto may require a building permit from the City of Toronto Building Division, particularly if the project involves structural penetrations or triggers the make-up air requirement. Budget $200–$400 for permit fees if applicable. If the hood requires new electrical wiring or a dedicated circuit, that work must be done by an ESA-Licensed Electrical Contractor — it cannot be bundled into the ductwork quote legally.

Hire a professional for this project. Roof penetrations, grease duct installation, make-up air assessment, and any associated electrical work all require qualified tradespeople. A poorly installed kitchen exhaust duct is a fire hazard, a moisture intrusion point, and a code violation that will surface during a home inspection when you go to sell.

Toronto Ductwork can match you with a local ductwork contractor experienced in GTA townhouse exhaust projects — get matched for a free estimate through the Toronto Construction Network at torontoconstructionnetwork.com/directory?trade=hvac.