Cooker hood installation: height, ducting and ventilation

Short answer: mount the hood 45–65 cm above an electric or induction hob, depending on the manufacturer, and at least 65 cm above a gas hob. Keep the duct short, straight and at least as wide as the hood outlet (usually 150 mm). In an apartment building, check where you are allowed to vent before you start.

1. How high should a cooker hood be?

The distance is measured from the hob surface to the underside of the hood. Manufacturers’ minimums differ:

*NEFF’s limits for gas: up to 3.9 kW per burner and 11.3 kW in total.

Three rules

1. If the hob and hood manufacturers disagree, the larger distance applies.
2. A hood mounted too high extracts poorly. Miele suggests 65 cm above electric hobs for working space.
3. With several appliances under one hood (for example a hob and a grill), the largest required distance applies.

2. Ducting: diameter, length and bends

• Diameter: usually 150 mm, and never narrower than the hood outlet.
  • Elica recommends 150 mm, with a 125 mm minimum.
  • A narrow duct cuts extraction and raises noise.
• Length and bends: as short and straight as possible. Elica suggests a total length of up to 6 m and ideally no more than two bends, both wide-radius.
• Flat ducts: fine if the cross-section is equivalent (150 mm ≈ 177 cm²).
• Horizontal runs: at least 1 cm of fall per metre.
• Cold spaces: insulate the duct where it passes through a cold loft, to avoid condensation.

3. Do you need a non-return flap?

A non-return (backdraft) flap closes the duct when the hood is off, so cold outside air and smells don’t come back in. Miele recommends always using one. Many wall and roof vents already have one built in.

An optional silencer also cuts fan noise and street noise coming in through the duct.

4. Ducted or recirculating?

• Ducting to the outside is the most effective: grease, moisture and smells leave the house.
• Recirculation cleans the air through a charcoal filter and returns it to the kitchen.
  • Use it when you cannot vent outside.
  • It only needs a socket.
  • The charcoal filter has to be replaced or regenerated regularly. See: cooker hood filter care.

5. Apartments, fireplaces and gas boilers

Shared shafts in older apartment buildings

The Estonian Association of Apartment Associations (EKÜL) lists connecting a fan hood to a shared ventilation shaft as a common mistake. In taller buildings, cooking smells can end up in neighbours’ flats. Ask the housing association or a ventilation designer before installing.

New apartments with heat-recovery ventilation

These often use a motorless hood:

• the apartment’s ventilation unit does the extracting;
• the hood’s switch opens a damper, and the unit raises the airflow;
• Estonian nearly-zero-energy design guides (EIS/KredEx) specify 25 l/s for the hood.

We stock motorless hoods and separate motors, for example Miele DA/DAS models without a motor plus external motors, and Gaggenau remote fan units. Browse our integrated cooker hoods.

Fireplace, stove or gas boiler in the same space

If an appliance takes its combustion air from the room and vents through a chimney, a ducted hood can create negative pressure and pull flue gases back indoors.

• Manufacturers (Miele, NEFF) allow no more than 4 Pa of negative pressure and require a permanent fresh-air inlet.
• A fresh-air valve or a window contact switch (the hood runs only with the window open) solves this.
• Never connect a hood to a flue or chimney that is in use.

Fire safety

The Estonian Rescue Board (Päästeamet) names kitchen extraction as the most fire-prone part of a ventilation system, because grease collects there. Under EVS 812-2, ventilation systems must be cleaned at least once a year.

6. Electrical connection

• Plug the hood into an earthed socket that stays reachable.
• If it can’t be reached, or the hood is hard-wired, an all-pole isolating switch is needed.
• No extension leads or multi-plug adapters.
• The power cable is often only about 1.3 m long, so plan a socket inside the cabinet near the hood.

Checklist before installation

• Distance from the hob is correct per both manufacturers’ manuals
• Duct diameter ≥ hood outlet, as few bends as possible
• Non-return flap in place
• In an apartment, the housing association has confirmed where you may vent
• With a fireplace or gas boiler, a fresh-air solution is in place
• Socket reachable inside the cabinet

FAQ

How high above an induction hob should a cooker hood be?

At least 45–65 cm, depending on the manufacturer. Check the installation manual for your model.

Can I connect a hood to my apartment’s ventilation shaft?

A hood with its own fan generally should not go into a shared shaft. New apartments use motorless hoods that work with the apartment’s ventilation unit. Ask your housing association.

What is a motorless cooker hood?

A hood without a built-in fan. An external motor or the building’s ventilation unit does the extraction.

Do you install cooker hoods?

Yes, across Estonia. See delivery and installation.

See also: all cooker hoods · cooker hood buying guide · hobs with integrated extraction