air plenum or return duct
air plenum or return duct
(OP)
Hello all
If we have a floor includes different units with different tenants,it is served by one AHU.
Which one is better?
- install a suspending ceiling in each unit to create return air plenum then connect all units together by making openings in unit's walls with fire dampers
OR
- using a return duct, also with fire damper when it penetrate the walls between units
Thank you
Attached is a sketch
If we have a floor includes different units with different tenants,it is served by one AHU.
Which one is better?
- install a suspending ceiling in each unit to create return air plenum then connect all units together by making openings in unit's walls with fire dampers
OR
- using a return duct, also with fire damper when it penetrate the walls between units
Thank you
Attached is a sketch





RE: air plenum or return duct
Ducted returns can be balanced.
RE: air plenum or return duct
If installing one fancoil per unit is not an option, I would prefer having a return duct going through a common corridor and getting into each room. It is better from an acoustic point of view and better for balancing.
Fire dampers are necessary depending on the fire zone criteria of the building.
RE: air plenum or return duct
Them's my two cents' worth.
Goober Dave