In the construction and industrial sectors, choosing the right insulation material is like “dressing” a building. Different materials have their own strengths and weaknesses in terms of insulation, safety, and durability. This article provides a basic comparison of various materials and offers recommendations for the use of aerogel materials.
I. Inorganic thermal insulation materials (non-combustible type)
Inorganic materials are typically made of minerals or glass fibers, and their biggest selling points are safety and longevity .
1. Rock wool/mineral wool
- Thermal insulation : Moderate. Thermal conductivity is generally between 0.035 and 0.045 W/( mK ).
- Fire resistance : Excellent . Class A non-combustible material, capable of withstanding temperatures above 1000°C, making it the top choice for fire protection in high-rise buildings.
- Hydrophobicity : Poor. Although there are hydrophobic rock wools, they are inherently prone to moisture absorption, and their thermal insulation performance decreases significantly after becoming damp.
- Durability : High. Stable properties, not prone to aging.
- Price : Medium to low.
2. Glass Wool
- Thermal insulation : Good. Slightly lighter than rock wool, with a slightly lower thermal conductivity.
- Fire resistance : Class A, non-combustible.
- Hydrophobicity : Poor. The fibers have large gaps, making them extremely prone to absorbing water.
- Price : Low. Commonly used for steel structure workshops or ceiling infill.
3. Foamed Glass
- Thermal insulation : Average. Thermal conductivity is slightly high.
- Fire resistance : Class A, non-combustible.
- Hydrophobicity : Excellent . Closed-cell structure, completely impermeable and non-absorbent.
- Durability : Extremely high. Lifespan equal to that of the building.
- Price : Expensive .
4. Aerogel Blanket
Aerogel is a nanoporous solid material with an air content of over 90% .
· Thermal insulation: Unbeatable . Its thermal conductivity is extremely low, typically between 0.015 and 0.020 W/( mK ) . This means that the same insulation effect can be achieved with only 1/3 the thickness of traditional materials .
· Fire resistance: Class A non-combustible . It has excellent flame-retardant properties and does not produce toxic fumes when heated.
· Hydrophobicity: Excellent . The overall hydrophobicity can reach over 99% , and it is breathable but not water-permeable, effectively preventing corrosion of pipes or walls (CUI).
· Durability: Extremely high. The structure is stable, and the service life is typically over 20 years.
· price: It boasts extremely high compatibility, high performance, and a long service life, with a moderate overall cost-effectiveness . Currently, it is mainly used in aerospace, petrochemical, heating pipe networks, or high-end ultra-thin energy-saving buildings.
II. Organic Thermal Insulation Materials (High-Efficiency Type)
Organic materials are mostly petrochemical byproducts, and their biggest advantages are their lightweight nature and excellent heat insulation .
1. Molded polystyrene board (EPS) / Extruded polystyrene board (XPS)
- Thermal insulation : Excellent . XPS is denser than EPS, and its thermal conductivity can be as low as 0.028 to 0.030 W/( mK ).
- Fire resistance : Poor . It is usually a Class B material, flammable, and will melt and shrink when heated, producing black smoke (flame retardants need to be added).
- Hydrophobicity : Good. Especially XPS, which hardly absorbs water.
- Price : Extremely low EPS, moderate XPS.
2. Polyurethane (PU/PIR)
- Thermal insulation : Top-notch . It has the lowest thermal conductivity among currently commercially available materials (approximately 0.022 to 0.025 W/( mK )).
- Fire resistance : Poor. Although slightly better than polystyrene board, it is still an organic material and will carbonize at high temperatures.
- Hydrophobicity : Excellent. High closed-cell ratio.
- Price : Relatively high.
III . Comprehensive Performance Atlas
To more clearly illustrate the differences between the various materials, please see the table below :
characteristic | Aerogel felt
| Rock wool (inorganic) | Foamed glass (inorganic) | Polystyrene (XPS) board (organic) | Polyurethane (organic) |
thermal conductivity | Extremely low (optimal) | middle | higher | Low (or good) | Extremely low (excellent) |
Fire rating | Class A (non-flammable) | Class A (non-flammable) | Class A (non-flammable) | B1/B2 grade (combustion oxidizer) | B1/B2 grade (combustion oxidizer) |
Moisture-proof/Water-repellent | Extremely strong | generally | Extremely strong | excellent | excellent |
Service life | Extremely long | long | Extremely long | Medium (prone to aging) | medium |
Environmental protection | Environmental friendly | Fibers may irritate the skin. | Environmental friendly | The production process consumes energy. | The production process consumes energy. |
Comprehensive unit price | Extremely high | economy | expensive | High cost performance | higher |
IV. Summary and Recommendations
Aerogels are almost “all-round champions” in terms of performance, but when making a selection, considering price, the following factors and application scenarios should be given priority:
1. Thickness , weight :
If your home renovation space is extremely limited (for example, you don’t want to take up space for interior wall insulation), or if there are requirements for load-bearing capacity and space for exterior walls, rooftops, etc., aerogel felt is a miracle cure.
2. Fireproof and durable
Aerogel felts offer advantages in scenarios requiring high fire resistance and long durability.
3. The special significance of hydrophobic properties :
While organic materials (such as polyurethane) are also hydrophobic, they degrade under long-term high-temperature conditions; aerogels, on the other hand, can maintain their physical hydrophobic properties even at temperatures above 400 degrees Celsius , which is why they dominate in fields such as industrial thermal pipelines and the treatment of localized thermal bridges .