And finally, this afternoon, we screwed down the cement board that we mortared down a couple of days ago, and then wrapped everything up in DPM plastic to protect our air supply from getting damp with heavy rain showers and wet ground.
Earth-tube-tunnel-wrapped-up
The final step is to put in stuttering to form the chimney that will come through the foundation and floor slab, plus shuttering down the side of the tunnel where it crosses under the main house foundation strip.