P0w3rGr0wZ
Member
I have an 8" 750 cfm. I wanted to know if I needed 8" duct or if I need to go 9" and clamp or tape it? Also I will be venting to attic so I wanted to know when I put the hole going to the attic if I can make it a 4" and just get a reducer say 8" to 4" or will that back things up trying to push through a smaller hole? Will it cause any problems?