So I have two basement rooms about 500 sqft each and I want to balance the humidity between both rooms. One room has a dehumidifier and drain so I'd like to cut a transfer grille between the two rooms so the dehumidifier can work through both rooms.
How big of a transfer grille should I have between the two rooms for the dehumidifier to be effective across both rooms. How far above the floor should the grille be mounted?
Looking at the original blueprints - it looks like they had planned to put 24x14 transfer grilles into the wall - but the actual building does not.