Compare the air path and cabinet location separately. “Freestanding” describes how a cabinet is placed; “ducted” describes how air reaches or leaves it. A freestanding cabinet may still use ducts. For a greenhouse layout decision, the useful comparison is direct-air equipment in the growing space versus equipment connected through a planned duct route.
Compare the two layouts
| Decision | Direct air in the growing space | Duct-connected arrangement |
| Space and service | Allow for the cabinet and local maintenance access | If the cabinet moves outside the growing space, service access moves with it |
| Air delivery | Identify the intake, discharge and crop area they serve | Identify the served area and the complete supply/return arrangement |
| Equipment location | Check conditions at the cabinet and its inlet | Check both the cabinet environment and the air arriving through ducts |
| Circulation | Examine local obstructions and discharge reach | Examine the duct delivery points and the circulation beyond them |
Remote placement is worth evaluating when cabinet space or service access is the constraint. Direct-air placement is worth evaluating when suitable local space and access are available. Neither description establishes an efficiency ranking.
Confirm the air path before choosing equipment
A duct proposal needs an operating-point check. AMCA's fan-curve guidance explains why the curve's conditions and the system resistance matter. Use the selected configuration's actual airflow and pressure information, not an assumption that an existing unit can be converted.
Keep equipment-specific mounting, connection and service requirements in the selection review. Also identify the condensate or other moisture-exit route appropriate to the chosen technology. Cabinet placement alone does not define these interfaces.
Check circulation where the crop grows
UMass greenhouse guidance describes how tall crops, hanging baskets, curtains and poor fan spacing can affect air movement. That is evidence for checking the crop air path, not a trial proving that ducted dehumidifiers outperform direct-air units. (UMass circulation guidance)
Mark the proposed cabinet, maintenance area, served crop zones and air-delivery points on the same layout. Then compare whether each arrangement can meet the same moisture duty under the same operating conditions. See greenhouse air distribution for the circulation question. Select the equipment configuration only after its documented interfaces and site conditions have been checked.
Related project questions
To connect equipment placement with the wider greenhouse assessment, review humidity variation across the crop and water removal and heat-recovery routes. For the wider project context, return to agricultural humidity control.
