Clive and Ruth Aims' cob cottage is warm in winter and cool in summer.
Yesterday, they opened their cottage off SH3 to a steady stream of visitors eager to see the fundamentals of building a cob house.
They also charged a small fee, which will go toward an earthquake-strengthing report for St Mary's at Upokongaro.
Mr Aim said living in an earth house had a ``satisfying, nice feel to it''.
``I love it. It feels really comfortable,'' Mrs Aim said.
The internal walls were good with humidity, and because they were able to breathe, they were a buffer to heat and moisture, and kept the house dry.