Whanganui earth house finished after three years

Tim Oldham (right) and Philip Baertschi are happy to have the whare finished. Photo / Bevan Conley

After a three-year "rollercoaster ride", the light earth house built on Māori land near Putiki in Whanganui is finally finished.

It's at the end of Hewitts Rd, on the 26.6ha Riri a Te Hori 2 Native Reserve, and was the project of the late Moari (Ari) Bailey, a descendant of the owners.

Her vision was for an eco-kainga of many houses and gardens. She was a high-earning IT analyst and funded much of this first experimental earth house herself, before dying from a brain tumour in September 2018.

At that time, the house was only a concrete ring foundation with framing and trusses.

Her partner Philip Baertschi, daughter Zoe Cochran and builder Tim Oldham soldiered on with the project in her memory. They had some devoted volunteers: Widge Rowden, John Handley, Ger Guiry and Graeme and Lynne Pearson.

Oldham, who is also an architect and earth building expert, put a final coat of oil on the earth floor of the 120 square metre house this week. Baertschi moves in soon and expects to have a housewarming in February or March.

He will keep a room free for Cochran, who has a life in New Plymouth and visits monthly.

Baertschi has worked for two years to finish the house, and, as Ari's partner, has a lifetime interest in the land. Now that work is over, he will have to make a life for himself in Whanganui and will look for other work or start a business.

"Putting a large sum of money into Māori land is always going to be a problem, because you don't have clear title. You can't sell the house at market rates or raise capital against it. It's complicated," he said.

Oldham will go to live in Ngaruawahia, and hopes to further the earthbuilding movement by doing design and project management rather than building. He'll take with him Lady Marmalade, the stray cat that has been his companion for the three years.

North and west-facing walls have a rain screen of redwood planks. Photo / Bevan Conley

On January 6 the house was empty, but ready for new occupants.

"It's taken three years, almost to the day, since I pulled up in my housetruck and broke the ground here," Oldham said.

A "truth wall" exposes the light earth material that fills the walls. Photo / Bevan Conley

Baertschi has been the labourer, mixing mud, straw and sawdust and pushing it into place.

"It went on forever and ever. It took a good year to just fill up the walls with the material," he said.

The result was a strong, warm and energy-efficient house that would last 100 or 200 years, Oldham said.

It has not been cheap. The initial estimate was $250,000 for its three bedrooms and large veranda. The actual cost has been $350,000 to $360,000 - without counting thousands of hours of free labour.

With Ari's aim of an eco-kainga now vanished, most of the reserve land has been leased for cattle grazing. It is to be partitioned through the Māori Land Court. Ari's brother Julian (Judd) Bailey plans to build a house on another piece when he retires.

Ari's wetland down in the valley is now "like Jurassic Park", Baertschi said.

"You need a machete to get around. It's a nature refuge for eels, ducks, pukekos, dragonflies and an amazing number of frogs. We have given something back to the environment, after taking for 150 years."

Roof trusses are from eucalypts harvested on a neighbouring property. Photo / Bevan Conley

The house was labour-intensive to build but less damaging to the environment than most. It used untreated timber from a local supplier, clay from the site, a minimum of concrete and has a lot of recycled and repurposed elements.

Whanganui District Council was easy to deal with, Oldham said.

"They put through our plans with very few questions, and the inspectors were great."

The whare's Colorsteel roof covers a large veranda to the south and east. The exterior walls there are plastered with a mud mixture and painted with a natural mineral silicate paint.

The north and west sides are more exposed to weather. There the light earth walls have a rain screen of redwood timber over windcloth and an air gap.

All the walls have macrocarpa framing, with a light earth mix of mud, straw and sawdust packed in, then left to dry and plastered. The mix is exposed indoors in a "truth wall" that also holds a painting of Ari.

The aluminium windows are secondhand and doubleglazed.

The interior walls are coated with plaster. The ceilings are a plaster-coated hessian, with wool insulation and an air gap above. The floor is insulated by 5000 wine bottles, all packed around with pumice. Packed in above that is 130mm (20 cubic metres) of light earth mix.

Its top surface was coated with a clay/sand plaster mix and polished with steel trowels, then oiled with tung oil. The result was similar to linoleum, Oldham said.

The kitchen has a woodburner with a wetback to heat water. Electricity is from the national grid, and water running off the roof is held in tanks.

Zoe Cochran made a bathroom mosaic in honour of her mother, Ari Bailey. Photo / Bevan Conley

The house has a flush toilet. Water from that, the shower and sinks goes into a worm composting system, then out to an irrigation field.

The doors are secondhand, with an assortment of knobs found in op shops. The lightshades hold LED lights and are made of Ari's preserving jars in "a nice tribute" to her vision for the place she had to leave.

• For more information, go to Creating Mama's Whare on Facebook.