Engineering behind timber tower plan
This country’s tallest wooden office block will have revolutionary design aspects including a rooftop device to protect the block during earthquakes, its developer says.
Sir Bob Jones, chairman of Robt. Jones Holdings, said all approvals had been granted for the block on the Leaders Building site, corner of Brandon St and Featherston St, and demolition of the existing block was well advanced.
“A revolutionary device on the roof involves a large weight on rollers. In an earthquake, this will roll in an opposite direction to the shake and nullify the movement.
“That’s the same principle of a sudden stop or crash in a car in which the driver is thrown forward,” Jones said.
“These have huge advantages over the conventional steel as they won’t buckle in an earthquake, which single factor has been the reason for the recent demolition of several new buildings in the city,” he said.
The 12-storey, 52m tall office block is made from laminated timber columns and beams which perform better in earthquakes than steel or reinforced concrete because they are less likely to buckle, Jones said.
“The internal removal of asbestos of the existing building took three to four months and finished a month back. Currently the internal demolition is going on and will be followed by the total demolition which is apparently quite quick,” he said.
Construction would start in August and finish around March next year.
Jones said he was inspired to build the wood tower after the topic rose to prominence last year and was being widely discussed.
“I rang the architects. ‘ Have you read this stuff?’ I asked. I received a cautious yes. ‘Then why don’t we do this?’ I asked,” Jones said.