Efficient stone with 24cm thickness regarding thermal insulation

Hello,

I am looking for a stone that provides the best thermal insulation at a wall thickness of 24cm.

What would you recommend?

This will be a single-story building.

Regards and thanks, CJC

Ytong or filled bricks.

Poroton, why only 24cm?

Poroton T10 or T12, or Poroton filled with mineral or Styrofoam. Also available as 36.5 cm stone. Then no exterior insulation is needed anymore.