Discussion Starter · #1 ·
OK, we are doing a DYI install of our HVAC system in our cabin. I had a local HVAC contractor map and do the J loads so I know how large my duct runs need to be and how many CFM's per room and register. However, what I cannot figure out is how I size my register boots. Is there a chart somewhere that tell how many cfm for what size of register?