Should I get a downdraft or overhead range hood for my NB kitchen island?

An overhead range hood is the better choice for most New Brunswick kitchen islands — it captures smoke, grease, and moisture far more effectively than a downdraft system, which is critical in NB's humid Maritime climate where excess cooking moisture promotes mold growth behind cabinets. Downdraft ventilation has its place, but only in specific situations where an overhead hood is physically impossible.

An overhead (ceiling-mounted) island range hood pulls rising heat, steam, and grease particles upward — the natural direction they travel — and exhausts them outside through ductwork routed through the ceiling and attic or soffit. This design captures 80–95% of cooking contaminants when properly sized. For a standard 30-inch cooktop, the hood should be at least 30 inches wide (36 inches is better for islands because there are no walls to contain airflow). For a 36-inch cooktop, a 42-inch hood is recommended. Expect to pay $400–$1,500 for the hood itself and $300–$800 for installation and ductwork, depending on how far the exhaust run needs to travel to reach an exterior wall or roof vent.

A downdraft system ($600–$2,000 for the unit) sits behind or beside the cooktop and pulls air downward and out through ductwork run under the floor or through the cabinet base. The advantage is a clean sightline — no bulky hood hanging from the ceiling, which appeals to homeowners who want an open-concept look. However, downdraft ventilation fights physics. Hot air rises, and pulling it downward before it disperses is inherently less efficient. Downdrafts typically capture only 50–70% of cooking vapours, and they struggle with tall pots and high-heat cooking like searing or stir-frying.

Why This Matters in New Brunswick

NB's Maritime humidity already creates moisture challenges in kitchens — summer relative humidity regularly exceeds 70% outdoors, and that moisture migrates indoors. If your range hood is not effectively capturing steam from boiling pots and cooking vapours, that moisture settles behind cabinets, under the sink, and inside wall cavities where it promotes mold and mildew. Recirculating hoods (which filter air and blow it back into the kitchen rather than exhausting outside) are even worse for this — in New Brunswick, always vent your range hood to the exterior.

For island installations, the ductwork routing is the main challenge. Overhead hoods require a duct run through the ceiling cavity, which works well in single-storey homes or kitchens below an accessible attic. In two-storey NB homes where the kitchen is on the main floor with bedrooms above, routing ductwork can be more complex and expensive ($500–$1,500 additional). A downdraft system avoids ceiling work by running ductwork through the floor — feasible in homes with basements or crawl spaces, which most NB homes have.

If an overhead hood truly will not work for your space, choose a telescoping downdraft that rises 10–14 inches above the cooktop when in use, rather than a flush-mounted one. The extra height significantly improves capture. Pair it with an induction cooktop, which produces less ambient heat and fewer airborne grease particles than gas cooking, improving the downdraft's effectiveness.

Budget $700–$2,300 total installed for either option. Minimum CFM (airflow) rating for an island hood is 600 CFM for gas and 400 CFM for electric or induction. Make-up air may be required by code for hoods rated above 400 CFM — your contractor should factor this into the plan.

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Looking for experienced contractors? The New Brunswick Construction Network connects homeowners with qualified professionals:

• Thirty Four Renovations
• Gionetterenovations