Aerogel is an ultralight, porous material that consists of approximately 95–99% air and is one of the best thermal insulators in existence. In construction, aerogel is used as high-performance insulation where space is limited.
How does aerogel work?
Aerogel is made by replacing the liquid in a gel with air without collapsing the structure. The result is a solid material with an extremely fine nanostructure that virtually blocks heat transfer.
The thermal conductivity (λ-value) of aerogel is around 0.013–0.016 W/(m·K) — two to three times better than conventional insulation materials.
Application
Aerogel is used in construction for:
- Heritage and retrofit projects — thin insulation boards where there is no room for thick insulation layers
- External wall insulation — aerogel insulation render combines insulation and surface finish in one layer
- Glazing — aerogel granules as a filling in translucent panels (translucent insulation)
- Pipework — as insulation around heating and cooling pipes
- Window frames — aerogel-filled profiles improve the thermal performance
Pros and cons
| Advantages | Disadvantages |
|---|---|
| Exceptionally low λ-value | Relatively expensive |
| Can be applied very thin | Fragile in board form |
| Translucent options available | Limited availability |
| Vapour permeable |
Related terms
- Insulation
- Building physics
- Mineral wool
- Sustainable building
- External wall insulation
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