Fiberglass ducts, commonly used in modern buildings for air conditioning and ventilation systems, are widely applied in various projects, including commercial, office, and industrial buildings, due to their excellent thermal insulation, sound insulation properties, and good construction adaptability. With increasingly stringent building energy conservation requirements, the long-term stability of fiberglass ducts has become a crucial consideration in design and construction. This article will evaluate the long-term stability of fiberglass ducts from multiple dimensions to help engineering technicians make informed decisions during selection and construction.

I. Material Characteristics of Fiberglass Ducts

Fiberglass ducts are made by combining glass fiber with bonding materials through a specific process. Their outer surface is typically covered with a moisture-proof and anti-aging protective layer. Glass fiber itself possesses high compressive strength, is corrosion-resistant, heat-resistant, and non-toxic, thus providing long-term stable performance in ventilation systems. The design of the moisture-proof protective layer is crucial for the durability of the duct; its main function is to prevent moisture penetration and avoid expansion, deformation, or performance degradation of the fiberglass duct in humid environments.

II. Environmental Adaptability

The long-term stability of fiberglass ducts is closely related to external factors such as ambient humidity, temperature fluctuations, and ultraviolet radiation.

1. Humidity Impact: In high-humidity environments, if the moisture barrier is inadequate or the duct is damaged, moisture may penetrate the fiberglass layer, leading to a decrease in the duct's insulation performance and even mold or corrosion. Therefore, in high-humidity environments, fiberglass ducts with good moisture barriers should be selected, or regular inspection and maintenance of the ducts should be performed to ensure long-term stable operation.

2. Temperature Fluctuations: In environments with large temperature differences, especially in places with frequent temperature changes, fiberglass ducts may be affected by the expansion and contraction of the material. While fiberglass has a certain degree of elasticity and flexibility, frequent temperature changes may cause the duct joints and fasteners to loosen or become damaged, leading to insulation failure. Therefore, properly designing the duct system to avoid excessive temperature fluctuations is crucial to ensuring its long-term stability.

3. Ultraviolet Radiation: Fiberglass ducts are typically used indoors, but in some special applications (such as roof ventilation ducts), they may be exposed to ultraviolet (UV) radiation. UV radiation causes aging of the duct surface materials, thus affecting the duct's strength and durability. Therefore, outdoor fiberglass ducts usually require a UV-resistant protective coating to slow down the aging process.

III. Degradation of Mechanical Properties

With increased usage time, fiberglass ducts may be affected by mechanical forces such as friction and vibration from airflow, leading to surface wear or structural loosening. Especially under conditions of high wind speed or significant vibration during system operation, the duct may experience localized damage or poor sealing, affecting insulation and airflow performance.

Therefore, to ensure the long-term stability of fiberglass ducts, in addition to selecting high-quality materials, installation and fixing measures should be strengthened to ensure that the ducts are not subjected to excessive stress during use. At the same time, duct joints and fasteners should be inspected regularly, and timely repairs and replacements should be carried out to avoid potential problems during long-term use.

IV. Maintaining Sound Insulation

A major advantage of fiberglass ducts is their excellent sound insulation performance, effectively reducing noise generated by airflow within the duct. However, with prolonged use, the internal fibers may be eroded by airflow and particulate matter such as dust, leading to a decrease in sound insulation. To maintain the sound insulation performance of the duct, the inner surface should be cleaned regularly to prevent the accumulation of dust and impurities.

V. Measures to Ensure Long-Term Stability

1. Regular Maintenance: Regular inspection and maintenance are essential to ensure the long-term stability of fiberglass ducts. Especially in humid, high-temperature, or high-vibration environments, check the integrity of the moisture barrier, the sealing of joints, and the presence of aging and damage on the surface.

2. Appropriate Material Selection: In high-humidity, low-temperature, or high-temperature environments, select specially designed fiberglass duct products to ensure superior moisture resistance, UV resistance, or high-temperature resistance.

3. Installation Specifications: During installation, ensure that the joints of the fiberglass duct are airtight to prevent air leakage; and use appropriate fixing methods to prevent loosening or deformation of the duct due to temperature changes or mechanical forces during use.

Fiberglass ducts are widely used in building HVAC engineering due to their excellent thermal insulation, sound insulation properties, and high mechanical strength. However, with increased usage time, environmental factors, temperature changes, mechanical stress, and other factors can affect the stability of the ducts. Therefore, to ensure the long-term stability of fiberglass ducts, in addition to selecting high-quality materials and appropriate specifications, regular inspection and maintenance are necessary to prevent problems such as surface damage and loose joints from affecting the normal operation of the system. Through scientific design and management, the long-term performance advantages of fiberglass ducts can be maximized, improving building energy efficiency and system stability.