New research into Aerogel-based insulation
Aerogel is often cited as the ultimate, state-of-the-art insulation solution for retrofit. This is because its low thermal conductivity (K-value) of 0.004-0.03W/mK and density of 10-300kg/m3 make it an excellent insulator. By comparison the thermal conductivity of mineral wood is 0.04-0.05W/mK and its density is between 11-100kg/m2. Until now the high cost and low strength of aerogel has limited its application in the built environment, but new research into aerogel-based insulation could transform its viability and application.
Fixit 222 is a new insulating plaster, developed by Swiss company Fixit and incorporating Cabot Corporation’s aerogel technology. The plaster was created with Swiss research body EMPA as part of a project to improve the energy efficiency of historic buildings. The aerogel-enhanced product is spray-applied directly onto brickwork and is said to have a thermal conductivity of less than 30mW/mK. The product is currently only available in Switzerland.
Swedish firm Svenska Aerogel has developed a production process that, it is claimed, could reduce the cost of aerogels by perhaps as much as 90%. The process allows aerogel to be produced continuously rather than in small batches, lowering costs. It also allows aerogel to be made in different forms, including pellets or powders, extending its applications.
A European research project Is also looking to bring down the costs of aerogel manufacture. High Performance insulation based on Nanostructure Encapsulation of Air (HIPIN) looks at five areas:
- increasing the solica content from 30% to 60% to make aerogel stronger and water and solvent resistant
- developing a faster, cheaper more efficient means of production
- developing new nano-materials that are more efficient and effective
- maximising longer term performance
- mixing aerogels into paint and coating systems and into plaster
In Germany, chemical company BASF is already developing an organic aerogel insulating panel material. The product achieves a K-value of 0.016W/mK.