Natural Ventilation Systems

Ventilation is critical to the health and production of animals in modern farming operations. Livestock producers are continuously looking for efficient and cost-effective ways to keep their barns in optimal environmental condition. In this article we are going to look at natural ventilation, which is sometimes called “passive ventilation”.

A natural ventilation system creates airflow using natural factors such as wind and temperature differentials, with the goal of producing a healthy and comfortable animal habitat. We will look at the benefits, uses, and considerations of natural ventilation barns for livestock.

Introduction to natural ventilation

Natural ventilation originated from the time when farmers would leave barn doors open to reduce moisture and heat accumulation in animal shelters. Modern naturally ventilated barns are much more advanced, but still follow the main principles of this age-old practice. Today, a sophisticated natural ventilation system plays a crucial role in enhancing the well-being of animals by drawing fresh air into the barn and expelling it through a series of strategically placed components.

Advantages of natural ventilation

Natural ventilation has several advantages over mechanical ventilation, including:

• Often less expensive to design and build
• Less expensive to operate
• Significantly less energy use, more environmentally friendly
• Less maintenance
• Provide ventilation during power outages*
• Provide natural light when curtains/panels are open
• Reduced animal stress and better working conditions due almost silent operation and less humidity, odour, and harmful gases

* Power outages in mechanically ventilated barns provide a significant risk of animal suffocation, the costs of which can be in the tens of thousands of dollars depending on the size of the facility.

Uses

Industry	Applications	Suitability for use
Dairy	All	Very common
Poultry	Especially turkeys	Sometimes
Swine	Farrowing and nursing	Rare
Swine	Finishing	Sometimes

Farmers that raise larger animals that require confinement typically use natural ventilation systems with sidewall and ridge apertures increasing airflow through the facility.

Considerations

Proper location of the building concerning prevailing winds and surrounding trees, structures and land formations is essential to the success of a natural ventilation system.

During periods of changing weather conditions, sidewall doors and inlets should be adjusted several times a day to avoid a sudden temperature change in the building.

Winter

• Inlets open
• During severe winter weather, inlets may be partially closed, NOT COMPLETELY CLOSED
• Sidewall and end wall openings closed and fastened

Mild winter/spring/fall

• Inlets fully open
• Upper sidewall and end wall openings adjusted to maintain a comfortable animal environment

Summer

• Inlets open
• Sidewalls completely open to provide air movement in the animal zone

Conclusion

In conclusion, ventilation stands as a crucial element for maintaining the health and productivity of animals in modern farming, and natural ventilation emerges as a cost-effective and efficient solution.

These systems have several advantages over mechanical alternatives, including lower costs, reduced energy consumption, and improved animal well-being. Natural ventilation systems offer benefits such as reduced stress, minimal maintenance, and the ability to provide ventilation during power outages.

Overall, natural ventilation systems, with their roots in age-old practices, continue to play a vital role in creating healthy and comfortable environments for livestock in modern agriculture.

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