Hans Bensemann, who lived in the house as a young child, later in life interviewed settler Christopher Frederick Carl Heinrich (Fred) Bensemann and Hans in turn was interviewed by the web-author in 1979 and 1983.

Fred Bensemann said he helped build the cottage when a young man. He learnt the trade from his father Cordt who had a busy building business in the 1850s and 1860s, which included the Sarau Hotel in 1857 and the Lutheran Church in 1865. Hans believed the house was built in the mid to late 1860s, but according to the Harvey family, descendants of English settlers George and Cornelia who commissioned the house, the construction date was 1859 (Fred would have been only 10 years old then). In adulthood Fred lived in a similar thick-walled sod house at Sarau which was built by Cordt. It seems likely that Cordt may have overseen the Mahana cottage project.

According to Hans, Fred was a large, well-liked old man with a passion for building (he also built E C and Ester's later wooden house across the road). Fred said that to build the Mahana earth cottage, the soil was first taken off and the site levelled, about 2'6" at end and a bit more at the other so as to get down to the clay. Ditches were then dug down where the walls would go, including inner walls. Stones from the creek were put into the ditches to try to prevent water coming up and decaying the walls. All the walls were started at the same time and built up at the rate of about a foot a day. The materials were native grasses, water and clay from a nearby bank which were all placed inside a container and mixed using a paddle contraption turned by oxen which walked around it in a circle. There was no sieving so small stones were left in the mixture. Large sod bricks were made from the mixture and compressed but not fully dried. No wooden framework was used to put the bricks into - instead they were stacked and merged into each other. The clay was left overnight to harden and the first job each morning was to cut off profusions using a very sharp spade so that the walls could be fashioned exactly vertical. Hans said the other method of building sod houses, using a framework, meant walls could be thinner as the clay was thumped down hard inside the wall mould, but with the Mahana house the walls had to be thicker ie from 19 to 24 inches thick. Windows were installed when the walls reached window height and an attic added for the kids' bedrooms. It took 11 days to build.

Hans said his father eventually took down the attic and added to the house so that it consisted of six small rooms, however it originally had only two rooms downstairs - the master bedroom and the kitchen/dining room containing the fireplace - and it has been restored that way. The children slept in the attic. The fireplace was made of firebricks, not clay. It was large enough to accommodate large logs and also sometimes the Bensemann children. Hans could recall sitting inside the fireplace to warm himself by the embers. He also painted a poignant word picture of a small dinner party around the table in front of the fire one night, just after war had been declared with Germany in 1914, with everyone speaking in German, as was the custom in those days. Among the group was the Lutheran Church Pastor Hoyer. Hans pretended to be asleep so he could eavesdrop and stay in the fireplace, rather than being sent upstairs. He heard the Pastor say to E C and the others in German: 'Don't worry, Germany will endure'.

After building a new wooden house across the road, EC and Esther sold the earth house in 1915 to the Dominion Orchard Company which used it as a bach for orchard workers. In the 1980s, members of the Bensemann and Harvey families became concerned about the condition of the building, which had had most of its front knocked out to house a tractor. The families did not confer but by a kind of magical coincidence the web author and Eileen Thawley each approached farmer Merv Uren within a fortnight of each other seeking to preserve the house. Merv kindly donated the land, the house was registered with the Historic Places Trust, the Thawleys gave some $6000 towards restoration and lots of other donations in time and resources were made by a large number of local trades-people and professionals (eg lawyers) and by the old Waimea County Council and new Tasman District Council. A trust was formed of Bensemann and Harvey descendants who researched and sometimes visited other earth buildings around the country and in working bees in late 1989 and through 1990 the house was refurbished and the wall rebuilt (this time with iron rods for reinforcement in the replaced wall, and with a hidden concrete foundation under all the outside walls). The bulk of the work was undertaken by the Thawleys.

In the early 1990s, the house was initially rethatched (in the way it was originally) on a voluntary basis by a trained German thatcher, Norbert Kleinschmidt, who has settled in the district. Since then period furniture has been installed in the house, plus a 'wax family', including children upstairs, and old horse-drawn vehicles and equipment in a side shed to make the whole experience as real as possible. Transparent perspex inner walls protect all this and makes it possible for the cottage and its 'inhabitants' to be visited at any time. Most of the hard work was done either by the Thawleys or under their direction.

The trust, a non-profit charity - the Somerset Farm Settlers Cottage Trust - aims to continue maintaining the building as a tourist attraction, heritage site and educational facility (especially for visiting school children). The work undertaken by Graeme and Eileen Thawley has included planting and maintaining an authentic 19th century garden between the road and the house.

Our largest recent project has been to install a more permanent thatch, at the cost of $12,600. It has been imported from South Africa. The previous thatch although lasting nearly 20 years, was sourced with great difficulty from local reeds which are no longer available and it was full of holes (although luckily we had iron underneath!)