Non-Insulated Flexible Duct

Structure and Materials of Non-Insulated Flexible Air Duct

Aluminum layer and spiral steel wire structure

The non-insulated flexible duct is manufactured from multiple layers of high-grade aluminum, providing strong mechanical strength and excellent resistance to kinking or collapse. Between the aluminum layers is a reinforced spiral steel wire that helps the duct maintain its shape when bent or stretched. This is the key factor that gives the duct high elasticity and mechanical durability, making installation easier in complex or hard-to-reach locations.

The combination of aluminum and steel wire increases pressure resistance while minimizing deformation during transportation and operation.

Outer foil layer characteristics

Covering the aluminum layer is a white foil outer layer that not only improves appearance but also provides flame-retardant performance according to ASTM D635 and UL 94 standards. This foil layer also helps reduce heat absorption and prevents moisture penetration, keeping the duct dry and durable under various environmental conditions.

Additionally, the foil surface makes cleaning easier and reduces dust and bacteria accumulation — an important factor for environments requiring high hygiene standards such as hospitals, shopping malls, and production areas.

Flexibility and airtight performance during installation

With its flexible structure, the duct can bend in multiple directions without complex connectors, making it suitable for limited-space duct systems. It can easily connect to round, oval, or rectangular outlets while maintaining airtightness and minimizing leakage.

In case of fire, the non-insulated structure allows toxic gases to dissipate quickly, helping reduce risks to people and property.

Advantages of Non-Insulated Flexible Air Duct

When choosing air ducts for HVAC or ventilation systems, users often consider insulated vs. non-insulated types. Each has its own strengths depending on application and environment.

Key advantages in installation and use

• Easy installation: High flexibility allows bending and fitting into difficult positions without specialized tools or many accessories.

• Cost-effective: Without insulation, the product is more affordable than insulated ducts, ideal for budget-focused projects.

• Multiple size options: Prodetech ducts are available from D100mm to D400mm for various systems.

• Flame-retardant and durable: Meets ASTM standards for flame resistance and tear strength, ensuring long service life in medium-pressure ventilation systems.

When to use non-insulated ducts

• When heat retention is not required or when used indoors with stable ambient temperature.

• In factories, warehouses, or commercial buildings needing basic ventilation without strict energy-loss concerns.

• Projects requiring fast installation and budget optimization.
   

  

Practical Applications of Non-Insulated Flexible Air Duct

Due to its simple, flexible, and cost-effective design, this duct is widely used in many applications, especially low- to medium-pressure ventilation systems.

Installation in high-rise buildings and shopping malls

Ventilation systems in high-rise buildings and malls are often hidden above ceilings, requiring lightweight, flexible, and easy-to-install materials. Non-insulated flexible ducts are ideal for this environment. They can be installed through gypsum ceilings, narrow technical shafts, and curved sections without complex fabrication.

Without insulation, the duct reduces total system weight and cost while still effectively supplying fresh air, exhausting air, and circulating airflow in enclosed spaces.

Low and medium pressure HVAC systems

Not all duct sections in HVAC systems require insulation. Short auxiliary ducts or ducts passing through temperature-controlled areas are suitable for non-insulated types.

Prodetech ducts support working pressure >2500 Pa for 2 hours and air velocity up to 30 m/s, ensuring continuous, stable, and leak-free airflow compliant with residential and light-industrial HVAC standards.

Role in ventilation and exhaust systems

Common applications include:

• Basement, technical room, and warehouse ventilation

• Hot air and odor extraction in industrial kitchens or processing areas

• Factory and workshop ventilation where heat retention is not required

The duct does not absorb moisture, resists mold, and contains no harmful materials, making it suitable for industries such as food processing, pharmaceuticals, and electronics.

Comparison: Non-Insulated vs Insulated Flexible Duct

Structural and performance differences

Cost and application comparison

• Cost: Non-insulated ducts are typically 20–40% cheaper than insulated ones.

• Application: Non-insulated ducts suit basic ventilation without thermal requirements, while insulated ducts are better for long duct runs or areas with large temperature differences (e.g., central air-conditioning systems).

Selection recommendations

Choose non-insulated duct if:

• Ambient temperature is stable

• Budget optimization is required

• Only airflow transmission is needed without insulation

Choose insulated duct if:

• Temperature inside the duct must be maintained

• Long duct runs may cause condensation

• Noise reduction is required

Non-insulated flexible air duct is a smart solution for projects requiring efficient ventilation, easy installation, and cost savings. With Prodetech quality and international certifications, the product ensures both technical performance and long-term operational safety. Proper understanding, selection, and installation will help maximize its effectiveness.