WOW! Many questions indeed... I try to answer one-by-one 1. The mud for the whole house is fermented at once per layer. So the base layer, the course mud (ara-kabe), which is the most volume is made in a pit dug near the house if there is a place for it. kzfaq.info/get/bejne/ZtGngZWUu6zbho0.html (a bit old, but great and authentic video about the whole process, as it is used in the maintenance of heritage buildings) The fermentation period can vary from several months to a year. In the old times, they also used the mud of the rice fields. Recently there you can also buy the fermented mud. 2. you can calculate the amount by multiplying the wall surface x 60mm 3. the pit for the fermentation is quite shallow, so it is possible to mix it with a special hoe. Recently hand plowing machine is also used. 4. smaller amounts, like for the middle layer, are mixed in containers. But these are not fermented that long, or sometimes not at all, based on the intended finish. The topcoat is rather left for some time being periodically mixed, to get even and free of chunks. 5. the lime coat is somewhat rainproof, although constant exposure to water is not favorable, so houses usually have deep eves. The lime coat has fibers and seaweed gue mixed in, so there is no protective covering layer. At the same time, the lime coat can consist of several layers, which have somewhat different ingredients. 6. Japanse lime plaster is not painted but applied with trowels forming dense layers. If applied well, and protected from direct rain, it can last for decades without regular maintenance. 7. The inside and outside walls can have various finishes ranging from lime to the countless types of (colored) earth plasters. These are also complex mixtures of earth, fibers, sand, glue, and other ingredients. 8. The technique is generally used for all the outside and partition walls as well. There are thicker wall types as well, used for fire-proof storage houses, castles, temples, and in certain regions for residential architecture in cities.

as far as I know "Tsuchikabe" technique

Probably has to do with building regulations in the country.

Hey! Thank you for your comment. Japanese have been using various kinds of drills since the old times, and there are several companies such as Makita, or Ryobi which are developing electronic hand tools. It is quite common to open holes or mortise with electronic drills and finish with chisels. At the camp, there were only limited tools available, so I had to stick with the drill only - which is actually OK in this case since it is not visible, and the under-structure of the wall connects somewhat loosely to the wooden frame to avoid tension.