Thanks for the PDF! So detailed the construction and thinking behind it.
I watched a couple of documentaries about walipinis in La Paz (Bolivia). Having to fight the altitude issue they came up with walipinis which turned out to be beneficial. So much to discover and gather knowledge about. Yeah, I'm with you when it comes to having these pits all over the globe.

Can't wait for it to get really cold so I can test it out by sleeping in there!

Now that's going to be a fun test 😉😊