Earth building makes sense

An earth built house in Queenstown, designed by Graeme North Architect. PHOTO/SUPPLIED

While it may all sound a little "new age", earth building is, in fact, a long standing form of construction.

In New Zealand, the oldest known earth building is Pompallier House in Russell, built in 1841.

Britain, France, Russia, Germany and China, as well as most other countries, have successfully built with what is an abundant and ever-present resource for hundreds of years.

Today, it is a legitimate, modern and healthy method of construction that is also sustainable and ecologically sound.

Earth building involves various techniques for turning sub-soils into useful building materials that are bound together with clay. Clay is the smallest particle in sub-soils and when it is dry a suitable mix will bind other soil aggregates such as sand and gravel together.

In Germany a standard building code for earth houses was in existence before World War II and today there are New Zealand standards for the testing of soils for suitability and for construction of earth buildings.

Earth building is great for creating a healthy indoor climate by regulating temperature, moisture and humidity -- no more mould and mildew -- and by absorbing sound, toxins and smells in the air. It is rot and fire-proof, with a very low carbon footprint.

Natural building has many advantages, can be incorporated into conventional designs and be very contemporary. Two builds using natural materials have recently featured on New Zealand Grand Designs.

The Earth Building Association of New Zealand (EBANZ) will have a stand at the Bay of Plenty Times Down to Earth Expo where you can find out more about this construction technique.

There will be hourly demonstrations of mud brick casting and earth plastering, a chance to win a membership of EBANZ and samples of rammed earth and mud brick walls to see.

- Down to Earth -- Sustainability & Lifestyle Expo takes place November 28 and 29 at ASB Arena, Mount Maunganui. Click here for more information.