| Frequently Asked Questions (Structures) |
What is a house tightness test and how is it conducted?
A good rule of thumb for checking a broiler house for tightness is to close all the inlets and doors in the house and turn on one tunnel fan and observe the static pressure difference between inside and outside of the house. The higher the static pressure difference the tighter the house is. Field tests and observations have shown many broiler houses to have a static pressure under this tightness test of under 0.03 to 0.05 inches of water (7.5-12.5 Pa). New houses that are being built where builders are paying special attention to minimizing leaks and tightness can have static pressure readings of 0.15 to 0.25 inches (37-62 Pa) during this tightness test. The performance difference in these houses from a ventilation standpoint is staggering. Loose houses use much more fuel, have poor litter quality, and less uniformity in temperature and air quality for the birds. Field results have shown that houses that have leak test readings as low as 0.03-0.05 inches (7.5-12.5Pa) will use 20-25% more fuel than those with leak test readings of 0.15 inches (37 Pa).
Product Categories: Ventilation, Structures
Industries: Poultry
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Could running water lines and electrical conduit along the house ceiling possibly hurt the effectiveness of my ventilation system?
Yes, indeed. During minimum or transitional ventilation, we want incoming air to stream along and hug the ceiling as long as possible, in order to get good air mixing. If pipes and conduits are placed on the ceiling above air inlets they can appreciably obstruct that good airflow stream, cutting its velocity down and directing outside air downward toward the birds. Alternative locations for water lines and electrical conduits should be found.
Product Categories: Structures
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How important is house tightness in doing a good job in ventilating under wintertime conditions?
Nearly all of the environmentally controlled poultry houses in the United States operate under the principle of negative pressure ventilation. This means that a slight suction or vacuum is placed on the house by the ventilating fans. Thus air is sucked into the house through any available openings because it is flowing from a slightly higher pressure area (outside) to a slightly lower pressure area (inside) the poultry house. This makes it possible to have air enter the perimeter of the house through carefully designed inlets that are an essential part of the ventilation system. But this works only if the house is otherwise tight, with few or no air leaks or "unplanned inlets." One of the key conditions that must be met to successfully operate a negative pressure ventilation house is that the house must be tight. In the last three years in the United States there has been a great push on to tighten up houses. Houses that have lots of air leaks through the curtains, doors, pad rooms, or ceilings have a lot of air entering the house that is not directed properly. Curtain flaps, seals on doors, patching of ceilings and in general tightening up houses have resulted in much more uniform air entry and therefore higher litter quality and uniformity of temperatures within the house. In addition, stopping or closing unplanned inlets (leaks) will greatly reduce fuel costs.
Product Categories: Structures
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