Flexible Ductwork: The Basics
Traditional air conditioning ducts are made from thin sheets of aluminum formed into tube like shapes and then coated with insulation. There are also rigid insulation boards that can be used to form ductwork without the need for the sheet metal to hold their shape. These two types of rigid ducts are ideal for main lines coming off of the air handler, but for smaller duct lines running to individual vents, flexible ductwork is often better suited for the task.
What Is In Flexible Ductwork?
As opposed to rigid sheet metal, flexible ducts are made with a coiled wire frame surrounding in a thin plastic or polyester sheeting. The wire frame allows to duct to hold its round shape while also allowing a greater amount of flexibility than traditional rigid lines. Once the wire frame has been coated in plastic sheeting, it is then insulated with either a thick glass wool or a combination of glass wool and polyester fiber. Once the ductwork has been properly insulated, it is then coated with a layer of polyethylene, another plastic substance with mostly industrial applications.
How Is Flexible Ductwork Used?
While the flexibility of ductwork is needed at times, most duct systems will not rely solely on flexible ducting due to its decreased efficiency when compared to rigid ducts. Instead, flexible ducts are used in conjunction with rigid systems, often found connecting main lines to individual vents. Branching flexible lines off the main fixed duct in order to reach rooms through tight angles or small spaces becomes much easier than trying to form a rigid line in the same manner. Flexible lines also allow for future adjustments without the need to disassemble and reassemble a rigid structure. In general, air conditioning installers will only use flexible duct work if the length of duct needed to reach the vent is under 15 feet. Even though the ducts are designed to be flexible, care must also be taken to ensure proper airflow is able to pass through.
While flexible ductwork may not be as energy efficient as rigid ducts, it works well as a component of an overall system when increased maneuverability is required.
Related topics:
February 19th, 2010 - 15:29
Great article thanks for the information