Winter Ventilation in Poultry Houses

As the days grow shorter and the months grow colder, one key factor in maintaining a healthy poultry flock is proper ventilation. While heat stress and air movement are typically big topics during the summer, proper ventilation during the winter months also warrants discussion. The primary goal of winter ventilation is to ensure proper air and litter quality through moisture removal.

Issues – Maintenance of broiler houses air flow has become more advanced in recent years thanks to improvements in user friendliness by equipment companies. However, the energy and fuel required to run these systems are often some of the biggest costs taken on by growers. With summer ventilation in the rearview mirror, it would be easy to consider cutting costs by backing off running these expensive fan systems in colder months. Unfortunately, improper winter ventilation can lead to litter and air quality issues, ultimately affecting flock performance. Minimum required ventilation is the principle of having enough air movement to remove moisture from the house and provide fresh, clean air to birds, with minimum energy expenditure and therefore lower costs. A major factor playing into minimum required ventilation is “tightness” of the house, or making sure no air is seeping in through open curtains, or cracks in siding or doors. Checking for openings, cracks, or other places where air seeps in could be vital to achieve an efficient and effective winter ventilation system.

Remedies – Since the main goal of winter ventilation is moisture removal, it is imperative to ensure a minimum ventilation rate that not only removes moisture but does so at minimal cost. As most know, warm air holds more water than cold air. In a broiler house, the issue is knowing how much outside, cooler air to bring in to remove moisture in the house, without bringing down temperatures or heightening energy expenditures. Broiler houses are designed to balance body heat from birds, mechanical heat from equipment, and supplemental heat from brooders, against heat losses from curtains, doors, and walls that draw out moisture. The pressure of this air movement is the key to ensuring ventilation programs are running properly. Mississippi State Extension recommends ceiling vents to be open 1-2 inches, while sidewall vents should be open 1.5-2.5 inches to ensure proper air volume. Static pressure in the house of 0.10-0.12 inches water column is the recommended level of static pressure to remove moisture, but could pose the threat of higher energy costs as fans need to work harder to move air into the house. Up to date equipment, such as stir fans, could reduce fuel cost by as much as 25% in older broiler houses and up to 10% in newer houses (Campbell et al., 2008).

In conclusion, a proper minimum ventilation program during winter is crucial for maintaining flock health and performance. While growers are always trying to save money, and reducing ventilation and energy would certainly reduce cost, the risk of poor bird health, performance, and market weights make a convincing case for proper winter ventilation.