HNZ house stands up to earthquake tests

Photo / APNZ

An old Housing New Zealand unit which underwent destructive earthquake testing today managed to stay standing - despite tests showing its structural strength was not up to scratch.

Two 550-horsepower rigs - each equipped with rams capable of pulling about 100 tonnes - applied force to the 1950s two-storey, four-unit structure in Upper Hutt to test its strength.

Housing New Zealand (HNZ) said the unit had been chosen because it was typical of a number of properties in the Wellington Region. Comprehensive test results, which would not be available until next year, would be able to be applied to a number of other buildings undergoing earthquake strengthening.

After today's testing had been completed, HNZ said in a statement that the building had not collapsed, but its structure had failed.

The organisation, which is considering investing $44.6 million over the next three years for strengthening and refurbishing of its properties, would release more information once they had assessed all the test results.

"The testing has the potential to significantly reduce the cost of the next phase of work we are doing to improve tenants safety," HNZ board chairman Allan Freeth said.

Housing Minister Nick Smith said today's testing had been the first time "destructive earthquake testing" had been carried out on a two-storey building in New Zealand.

"We need more reliable information about how weak or strong houses of this age are so we can make better informed decisions on their repair and replacement."

Information from the tests would be made public when they were ready, and would be "invaluable to all property owners making assessments on the relative strength of older buildings," Dr Smith said.

"We are about to embark on a massive programme of earthquake strengthening for more than 150 Housing New Zealand buildings at a cost of tens of millions of dollars. This destructive testing enables us to compare actual strength to predicted strength to ensure we make better decisions on maximising safety for tenants while minimising cost to tax payers," he said.