My family once built something like this. We used ready-made roofing materials, but the rest was branches and small tree trunks, dried grass, and clay. The process went something like this: dig a hole until you hit clay. Put four posts for the corners such that the hole is in the middle. Put up a basic slanted roof and put straight branches over it, nailing it all together. Put grass and mud mixture on top of that and let dry, then cover with roofing material. Now you have a shady place to work! Keep digging clay out of the center hole and store it. Put more posts where walls will go. They don't have to be super close: 1-2 inches apart is just fine. Mix clay with water and grass again to make mud. Fling it against the newly created walls and smooth it out with a board. Wait to dry. Repeat form the inside and out until you have a solid 6-8 inch wall and none of the wood is exposed. The door was another ready-made item but technically didn't have to be. Once the four walls are up and the door is installed, create a floor and a hatch into your new cellar.
We then expanded this one room, adding three more. We built a wood burning stove in one of them using clay bricks and another stove outside. Once you can stay at a place like this work goes much faster. There is a huge advantage to using clay as the main material too: it keeps the inside very cool, and it is very cheap and easy to work with.
Then we got even crazier and bought a bunch of bricks. We laid the foundation of a brick house around the mud hut, then built up walls around the mud hut. Once the walls and the roof was up, the sledge hammer took care of the mud hut and the materials were carried out the front door.
Edit: oh, and we had no power at this location, so we did all of this using only hammers, manual saws, screw drivers, and a manual drill. Almost all the nails and screws were salvaged.
It held up great. The clay cured enough in the sun to not be bothered by it. It stood for 3 or 4 years IIRC. After that we built the brick house around it.
The reason we built this was because we got a plot of land to farm, but it was a ways away from where we lived, so we needed some shelter to stay there during the summers. Another requirement was that it had to be resistant to people trying to break in to steal stuff (it was).
We then expanded this one room, adding three more. We built a wood burning stove in one of them using clay bricks and another stove outside. Once you can stay at a place like this work goes much faster. There is a huge advantage to using clay as the main material too: it keeps the inside very cool, and it is very cheap and easy to work with.
Then we got even crazier and bought a bunch of bricks. We laid the foundation of a brick house around the mud hut, then built up walls around the mud hut. Once the walls and the roof was up, the sledge hammer took care of the mud hut and the materials were carried out the front door.
Edit: oh, and we had no power at this location, so we did all of this using only hammers, manual saws, screw drivers, and a manual drill. Almost all the nails and screws were salvaged.