Y'see the ones I know of have hurdle walls. Those walls are either doubled and stuffed with bracken and the like, or they're mudded over like wattle and daub.
I know of a lot of Duns that are built using stone like that, but it just kind of seems overkill for such a small dwelling.
In the ones I know of the roof isn't supported on the walls, it's supported on a ring of timbers set on posts.
The round house doesn't stop the weather, it baffles it, and creates a warm dry space, that because of the smoke from the hearth, is pretty much insect and pest free.
Above head height there's smoke, as it kind of drifts up to fill the cone then spills out at the eaves.
As I said, interesting to see
something different, but it seemed awfully labour intensive.
Good on them giving it a go