Several months ago I came across a product called aircrete or foamcrete. It has been around for a few decades but as of today has mostly been used as an insulation material, while its potential for construction has yet to be fully appreciated.
Aircrete is basically mortar filled with air; sand, cement and a foaming agent ~ a type of soap. Special mixing equipment is required to make it but the process is not high-tech, just different from mixing concrete or mortar the conventional way.
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