In HVAC systems, various types of ducts are used, among which fiberglass ducts are widely used due to their integrated insulation, sound absorption, and air delivery functions. Many users ask when selecting ducts: Are fiberglass ducts composite ducts? What are the differences between fiberglass ducts and traditional metal ducts?

I. Fiberglass Ducts are Composite Ducts

According to common classification methods in the HVAC industry, fiberglass ducts are a type of composite duct.

A composite duct refers to a duct system composed of two or more different materials, possessing multiple functions such as structural integrity, insulation, or sound absorption. Fiberglass ducts are formed through multi-layered material composites, thus meeting the definition of a composite duct.

Key Conclusions:

Fiberglass ducts belong to: Composite ducts

Fiberglass ducts belong to: Insulated ducts

Fiberglass ducts belong to: Non-metallic composite ducts

Fiberglass Ducts

II. Why are fiberglass ducts classified as composite ducts?

1. Multi-layer Composite Structure

Fiberglass ducts are typically composed of the following layers:

Inner layer: Fiberglass sound-absorbing and heat-insulating layer

Middle layer: Reinforcing structural layer

Outer layer: Moisture-proof and protective surface material

This multi-layer structure is not made of a single material, conforming to the basic characteristics of composite materials.

2. Multiple Functions in One

Compared to single-layer metal ducts, fiberglass ducts simultaneously possess the following functions within the same structure:

Air delivery function

Thermal insulation function

Sound absorption and noise reduction function

Formaldehyde-free fiberglass ducts

III. The Position of Fiberglass Ducts in the Duct Classification System

From the perspective of duct system classification, common duct types include:

Metal ducts (such as galvanized steel sheet ducts)

Non-metal ducts

Composite ducts

Fiberglass ducts are generally classified as non-metallic composite ducts and are widely used in building air conditioning and ventilation systems.

IV. Comparison of Fiberglass Ducts with Other Duct Types

1. Fiberglass Ducts vs. Metal Ducts

Metal ducts typically lack inherent insulation properties, requiring additional insulation layers; while fiberglass ducts, being composite structures, reduce the need for subsequent insulation processes.

2. Fiberglass Ducts vs. Traditional Composite Ducts

In composite duct systems, fiberglass ducts are representative products with glass fiber as their core material, differing from other composite ducts in material composition and performance focus.

Formaldehyde-free, sound-absorbing fiberglass ducts

V. Common Applications of Fiberglass Ducts as Composite Ducts

Based on their composite structural characteristics, fiberglass ducts are commonly used in:

Commercial building central air conditioning systems

Public building ventilation systems

Places requiring noise control

Projects requiring overall system energy efficiency

VI. Conclusion

Based on their structural composition and industry classification standards, it is clear that fiberglass ducts belong to composite ducts and are an important type within non-metallic composite duct systems. Its multi-layered composite structure determines that it has multiple functions such as air supply, heat preservation and sound absorption in HVAC systems.