Aircrete Dome

Aircrete is an innovative construction technique using concrete with bubbles, which is also very inexpensive. The material is fireproof, insect proof, waterproof, offering significant thermal and acoustic insulation. It can be cut, carved, drilled and shaped with wood-working tools.
The photo above is featured on https://www.domegaia.com/ . The team there appears to be outstanding with a wonderful mission that is in alignment with ours.