Frequently asked Questions

Isn't earth building relatively new in New Zealand?

No, its been done satisfactorily for over 100 years up and down the length of the country. Our oldest known earth building, Pompallier House, in Russell, stands two stories high and was built in 1842.

Isn't earth building (traditional to the drier climates of the Middle East, North Africa and the American Southwest) unsuited to New Zealand's wetter weather?

Earth building is not just traditional to the drier areas of the world, but Britain, France, Russia, Germany and China, as well as most other countries, have successfully built with this abundant and ever present resource for hundreds of years. In Germany a standard building code for earth houses was in existence before World War II. New Zealand earth buildings up and down the length of the country have successfully withstood rain, wind, heat, freeze and thaw for up to 150 years.

Don't earth walls revert to mud when it rains heavily

Roof overhangs of at least 6OOmm all round are recommended as essential for earth buildings, as they should likewise be for all houses of conventional materials. This, together with a good foundation that stops ground moisture getting in to the bottoms of the walls, ensure that earth buildings will last for hundreds of years (note that these comments also apply to ALL buildings made from conventional materials). Roof overhangs are also essential to control unwanted summer sun.

In New Zealand stabilisers such as cement, bitumen emulsion or slaked lime are often added to improve the strength and weathering of the earth walls. Alternatively, unstabilised earth walls can be given added weather protection by a plaster or some other kind of coating (in the same fashion that timber, fibre-cement and concrete block are given coatings to make them fully weather proof).

What about the susceptibility of earth buildings to earthquakes?

All over New Zealand and in all seismic zones of this country, earth houses have successfully withstood earthquakes. Wellington, Nelson and Marlborough are well known for being in our country's worst seismic zone, yet they have many examples of long-standing earth buildings. Badly built/designed buildings of steel, reinforced concrete and timber will also suffer damage, and even be totally destroyed in severe earthquakes.

Aren't local bodies against earth buildings?

Territorial Authorities (TA'S) are not specifically "against" any specific type of structure. If when you approach them with an unfamiliar building medium, you provide proper information about weather resistance, durability, strength and engineering calculations, they usually issue a building consent after due consideration of your submission. EBANZ knows of no case where, after following this procedure, a building consent has still been refused.
The New Zealand Earth Building Standard will assist most applications