Hi there: I’m trying to calculate undercuts necessary for balancing an HVAC system in a couple new residences. But then it occurred to me, that since all the doors are pocket doors, and since the Johnson Hardware we’re using specifies a 3/16″ gap between the jambs and the door panel on either side of the door, that this gap could be considered a “transfer grille” of sorts… The smallest 30×80″ door would therefore have the equivalent of 20in2, not including any undercut.

Am I thinking about this in the right way? Do these 3/16″ gaps give me what I’m assuming they do, in terms of airflow?

thanks!