How to Size Kitchen Ventilation

Wall Mount Installation
100 CFM per foot of width.
For example: 3 foot wide stove top requires 300 CFM exhaust fan.

Island Mount Installation
150 CFM per foot of width.
For example: 3 foot wide stove top requires 450 CFM exhaust fan.

Note: If using gas for cooking, it is recommended that
the hood liner be 6" wider than the cooktop.