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Flex versus rigid ductwork for the HVAC system in your home

Heating, ventilation, and air conditioning (HVAC) refers to the technology used to create indoor comfort within the house. The objective of a good HVAC system is to ensure that there is thermal comfort in the house, as well as quality air. The technology employs heating components, air conditioners, and ductwork to facilitate the flow of air from one point to another. The ductwork is as important as the other HVAC equipment, which makes it elemental for you to have an appropriate one installed. Here are some details on both flex and rigid ductwork to help you make the right choice regarding the ductwork for your HVAC system:

Flex ductwork

Flex ductwork for an HVAC system is made from thin aluminium foil or plastic. A long coil of wire or metal strap is used to support the whole cross section of the ductwork. During installation, wires or cotton straps are used to support the ducts against poles to hold them in position. Preferably, wide straps should be used to support the ductwork because thin wires increase the constrictions along the ductwork. These constrictions can interfere with the flow of air in the ducts, limiting the efficiency of ventilation and thermal regulation.

Flex ductwork is cheaper than rigid metallic ductwork. Its installation also takes a shorter time, which costs you less in terms of labour. Moreover, the flexible nature of the material used to make flex duct enables it to pass through tight spaces and make sharp turns. This is often difficult when using rigid ductwork.

On the downside, the material used to make flex ductwork is not as durable as that used in rigid ductwork. For instance, the material can be easily punctured by rodents or become brittle and collapsible after being used for many years.

Rigid ductwork

Rigid duct for your HVAC system is made using thin metallic sheets of aluminium. The interior of these ducts is smooth, which facilitates the flow of air between the heating or ventilating component and the room. Unlike flex ductwork, the rigid alternative has no constrictions at the points of support, which improves the flow of air. 

Insulating the outer side of the rigid ducts ensures that no fibres make their way into the air stream, which helps to keep the air pure. The insulation also helps to protect the ductwork against harmful ultra-violet rays and damage by rodents. However, rigid ductwork is hard to work with in tight spaces and around bends. It is also more expensive than flex ductwork because of its durability and improved efficiency in terms of air flow.