AAC or Autoclaved Aerated Concrete was developed by Swedish architect J Axel Eriksson in 1923. The key features that it possessed at that time was providing structure, insulation and resistance to mold and fire. Over the years this design has been improved to provide and array of different features like pest resistance and superior strength. Initially what was used for just industrial purposes now can be used for a lot more including residential purposes too.
AAC blocks much like carbon fiber; light and strong. AAC blocks have the tendency to float on water and at the same time the ability to withstand tremendous pressure from storms as well as earthquakes.
AAC is like wood except they don't catch fire! They are non-combustible with a UL fire rating of 4 hours for a 4 inch non-load bearing wall. Also, when exposed to fire, AAC gives off no toxic gases, but at the same time there is full flexibility of customization. It can be cut and shaped in to any structure, in many cases its better than wood, something like a whole flight of staircase can be shaped from single blocks.
Apart from fire resistance, they have great thermal capabilities especially for a tropical country like India and even more so in places where there is great fluctuation on day and night temperature, the temperature inside remains more or less the same. Its cellular structure offers these unique thermal properties.
A popular concept that is emerging these days is that of the green buildings. AAC blocks go well with this concept as it is produced in a pollution free fashion using minimum energy and non-toxic ingredients.
These walls are protected against pests like termites. They have amazing sound absorbing capacity and are ideal for places like schools and hospitals.