So, my flower and mother/clone/veg room are in a room in my basement. I'm currently ducting the exhaust off my 1000w hps into the main return trunk on the houses HVAC system. That worked fine for 1000w but with the addition of another flower light I'll be overheating the house in all but 20* weather. So, I need a seperate duct circuit to get any additional heat up into my attic where it will dissipate naturally. Obviously, I'm aware that carbon filtering will be required. I'm already familiar with this aspect.
So, aside from the "where to hide the 6" duct" issue how about head loss per foot of duct? I know, at a minimum to get the peak of my attic I'll need 19+ feet of ducting from the point that it exits my room. I'm just looking for a rule of thumb basically. Similar to how we know that flow will be reduced by ~50% for every 90* elbow. So, 1' of 6" duct = x% flow loss? Also, how much do duct mufflers cut flow? Don't want the neighbors hearing the jet from the attic if I'm going to need 1000+CFM.
So, aside from the "where to hide the 6" duct" issue how about head loss per foot of duct? I know, at a minimum to get the peak of my attic I'll need 19+ feet of ducting from the point that it exits my room. I'm just looking for a rule of thumb basically. Similar to how we know that flow will be reduced by ~50% for every 90* elbow. So, 1' of 6" duct = x% flow loss? Also, how much do duct mufflers cut flow? Don't want the neighbors hearing the jet from the attic if I'm going to need 1000+CFM.