Search Results for ‘ducting calculation’

I’m trying to find a straight answer. I’m replacing my supply ducting. Water leak rusted them. My question is, What’s the easy way to figure the new plenum? I am going to round. I keep finding different opinions. One says make it the same size as the A coil box. I’m assuming if not actual...

I am replacing an old noisy bathroom exhaust fan that currently has a 4" roof jack/cap and 4" ductwork. According to the proper calculations, I would need a new exhaust fan rated at 190 CFM. However, I can't find any 4" exhaust fans with CFM ratings this high. The roof is 7/12 pitch and I...

I have a question about how to calculate duct size when there are multiple supply or return vents in the same room. Say I have a room that requires 400 cfm. Using a ductulator for flex ducting tells me I need 11" diameter. Now if I have two vents at opposite sides of this room, how do I...