Range Hood Duct Size - Complete Guide (With …
The minimum duct size for a range hood is 4”, which is ideal for range hoods 400 CFM and under. The higher the cubic feet per minute, the larger the duct you’ll need. At 600 CFM, the minimum duct size is 6”. At 900 CFM, the minimum duct size is 8”. Finally, at 1200 CFM and above, consider a 10” diameter duct or larger.