Hybrid-Positive Pressure System: A New Design Concept
Most poultry houses are designed using a negative
pressure ventilation program, but free-range facilities
must be thought about differently. Because free-range
farms must provide outside access for birds, pop-doors
are built into the walls. These doors are often required
to be open for long periods of time, if not continuously,
when birds are present. With negative pressure
ventilation, pop-doors act as air inlets and create cold
drafts along the floor during winter, resulting in wet
litter by the doors and uneven house temperatures.
To solve this problem, houses can be designed using
a hybrid ventilation scheme. This hybrid design
combines a natural or negative ventilation scheme with
a positive pressure design to accommodate free-range
birds during all seasons.
The key to successful positive pressure design is the use
of a centrifugal mixing fan. Our Z-Pro™ Hemisphere®,
the newest addition to the Hemisphere line, works in
any floor bird application. The patented design of the
fan pulls air – from above and below – into the center
of the fan, where it is mixed and pushed out towards
the sidewalls. This creates a constant, slow-moving air
current along the walls and floor of the bird space.
The end result is the ideal bird environment –
a uniformly well-ventilated, comfortable house that
balances bird comfort, consistent temperatures, and
litter quality.
