Glass wool and polyurethane are two widely used insulation materials in building insulation, industrial equipment insulation, and HVAC systems. They differ significantly in material structure, insulation performance, fire safety, and construction methods. A proper understanding of the core points of comparing glass wool and polyurethane materials helps in making more informed selection decisions in different engineering scenarios. This article will systematically compare glass wool and polyurethane insulation materials from the perspectives of material properties, thermal conductivity, fire resistance, and application scenarios.

I. Comparison of Material Structure and Basic Properties

1. Material Structural Characteristics of Glass Wool

Glass wool is an inorganic fiber insulation material, mainly made from quartz sand, limestone, etc., which are melted and fiberized at high temperatures. Its interior consists of numerous interwoven, long, thin glass fibers, forming a porous structure filled with still air, thus reducing heat transfer.

Glass wool itself is non-combustible, has good stability, and also possesses certain sound absorption and noise reduction capabilities, making it widely used in building and HVAC systems.

2. Structural Characteristics of Polyurethane Materials

Polyurethane insulation materials are organic polymers, typically formed into a closed-cell foam structure through a foaming process. Its fine pores and strong airtightness make it a typical high-efficiency insulation material.

Polyurethane can be applied through on-site spraying or prefabrication, offering strong adaptability. It is commonly used in roofing, cold storage, pipe, and equipment insulation systems.

II. Comparison of Thermal Conductivity and Insulation Effect

1. Thermal Conductivity of Glass Wool

The thermal conductivity of glass wool is generally between 0.034 and 0.040 W/(m·K). In conventional building insulation, duct insulation, and equipment insulation, it provides stable and reliable insulation effects. Its thermal conductivity is relatively balanced in normal and low-temperature environments.

2. Thermal Conductivity of Polyurethane

The thermal conductivity of polyurethane materials is typically between 0.020 and 0.028 W/(m·K), significantly lower than that of glass wool. This means that, while achieving the same insulation effect, polyurethane requires a thinner material layer, making it suitable for projects with limited space or high energy-saving requirements.

III. Comparison of Fire Resistance and Safety

Fire Resistance of Glass Wool

Glass wool is an inorganic, non-combustible material. It will not burn or release large amounts of harmful gases under high temperatures and fire conditions, resulting in high fire safety. Therefore, glass wool is commonly used in building envelopes and HVAC systems with high fire resistance requirements.

Fire Resistance of Polyurethane

Polyurethane is an organic material and is inherently flammable. In engineering, flame retardants are typically added to improve its fire resistance. Although flame-retardant polyurethane can meet some building code requirements, its overall fire safety rating is still weaker than that of glass wool.

IV. Comparison of Moisture-proof and Condensation-proof Performance

1. Moisture-proof Characteristics of Glass Wool

Glass wool has a fibrous structure. If not used in conjunction with a moisture-proof layer, moisture may penetrate the insulation layer, affecting the insulation effect. Therefore, when used in pipes or humid environments, aluminum foil or other moisture-proof layers are usually required.

2. Moisture-proof Advantages of Polyurethane

Polyurethane has a good closed-cell structure and low water vapor permeability, giving it strong moisture-proof and anti-condensation capabilities. This makes it advantageous in environments such as cold storage and low-temperature pipelines.

V. Comparison of Construction Methods and Applicable Scenarios

**Application Characteristics of Glass Wool**

Glass wool is commonly used in the form of boards, rolls, or pipes. Its construction methods are mature and suitable for large-area laying and standardized installation. Its good flexibility makes it suitable for air ducts, ceilings, and building envelopes.

**Application Characteristics of Polyurethane**

Polyurethane can be prefabricated or sprayed on-site. It can tightly adhere to complex structural surfaces, reducing thermal bridging problems, making it suitable for irregularly shaped structures or space-constrained areas.

VI. Comparison of Typical Application Scenarios

| Application Scenarios | Glass Wool | Polyurethane |

| -------------- | --------- | --------- |

| Building Wall Insulation | ✔ Commonly Used | ✔ Commonly Used |

| Duct Insulation | ✔ Preferred | △ General |

| Cold Storage Projects | △ General | ✔ Preferred |

| Roof Insulation | ✔ Applicable | ✔ Applicable |

| Areas with High Fire Safety Requirements | ✔ Preferred | △ Restricted |

VII. Comprehensive Analysis and Selection Recommendations

In summary, glass wool and polyurethane materials differ significantly in their performance orientation:

Glass wool focuses more on fire safety, sound absorption, and stability.

Polyurethane emphasizes high-efficiency insulation, thin-layer design, and moisture-proof performance.

In engineering practice, a comprehensive evaluation should be conducted based on specific temperature conditions, fire rating, space limitations, and cost requirements to select the insulation material that best meets the project's needs.

A comparative analysis of glass wool and polyurethane materials reveals that they are not simply substitutes, but rather each has its own advantages in different application scenarios. Appropriate material selection and scientific design are key to achieving long-term energy conservation and safe operation of building and industrial systems.