Quick Answer: Choose a chimney that is at least as wide as your hob, with enough suction for the way you cook. Heavy frying and tadka need stronger suction than light boiling. Pick a type that suits your layout: wall mounted for wall hobs, island type for island hobs. Plan the duct route before the kitchen is made, because the chimney, the cabinets and the wall all depend on each other. Key Facts: The chimney should cover the hob fully. A common rule is to match or exceed the