Natural ventilation and smoke vantilation North America : Solutions :

Natural_ventilation

Natural ventilation systems rely on pressure differences to move fresh air through buildings. Pressure differences can be caused by wind or the buoyancy effect created by temperature differences or differences in humidity. In either case, the amount of ventilation will depend critically on the size and placement of openings in the building. It is useful to think of a natural ventilation system as a circuit, with equal consideration given to supply and exhaust. Openings between rooms such as transom windows, louvers, grills, or open plans are techniques to complete the airflow circuit through a building. Code requirements regarding smoke and fire transfer present challenges to the designer of a natural ventilation system. For example, historic buildings used the stairway as the exhaust stack, a technique now prevented by code requirements in many cases.

DESCRIPTION

Natural ventilation, unlike fan-forced ventilation, uses the natural forces of wind and buoyancy to deliver fresh air into buildings. Fresh air is required in buildings to alleviate odors, to provide oxygen for respiration, and to increase thermal comfort. At interior air velocities of 160 feet per minute (fpm), the perceived interior temperature can be reduced by as much as 5°F. However, unlike true air-conditioning, natural ventilation is ineffective at reducing the humidity of incoming air. This places a limit on the application of natural ventilation in humid climates.

USEFUL FACTS

All our controlled natural ventilation products meet the very latest standards for buildings that are comfortable and energy-efficient. From drive and control technology up to integration in building control systems thanks to intelligent bus technology, we can provide the solutions to help you implement your complex, long-term strategies for energy reduction and climate control.

Cost-efficient ventilation systems with motor-operated win- dows improve the air in the room and keep the temperature comfortable. Depending on the type of building or concept of the room, various methods can be implemented to provide controlled natural ventilation: Single-sided ventilation, cross venti- lation and hybrid ventilation are suitable for use in schools.