Base-isolation method 'barely used in NZ'

7:08 pm on 13 March 2012

An earthquake engineer says many construction companies are scared of adopting new quake-resistant building designs because they do not realise how simple and cost effective they are.

The Canterbury Earthquakes Royal Commission is investigating new building and design technologies that could change the way Christchurch rebuilds.

A technical director of Holmes Consulting, Des Bull, says the way buildings are currently constructed is well suited to making use of new technologies, which will generally make the job easier.

The commission heard about a recently constructed building in Christchurch that made use of several new techniques and ended up being $40,000 cheaper than if it had been built conventionally.

Professor Bull says New Zealand is much slower than the rest of the world in taking up new building technologies, even though it is a world leader in designing them.

The commission was told that base isolation - a technique invented in New Zealand that can make buildings much safer - is barely used here.

Trevor Kelly, of Holmes Consulting, says base isolation separates the building from the ground, allowing it to move with, rather than against, a quake.

He says the technique will not make construction any cheaper, but does make the building much safer.

The method, which has been compared to adding suspension to a car, was developed by a New Zealander in the 1970s.

Only 12 buildings in New Zealand use it, with one in Wellington the first in the world.

But Megan Devine of Robinson Seismic said its use took off in other countries after substantial earthquakes, and she expects the same to happen here.