More and more high-rises

Press, 18 December 1986, Page 34

More and more high-rises

Dr Alan Reay of the Christchurch engineering consultancy, Alan Reay Consultants, says Christchurch residents can look forward to more high-rise buildings in the innercity.

He says the profit from building ownership lies in leasing and to be an attractive lease proposition, a building needs to have features which set it apart from other buildings.

“Being one of the highest buildings in the city would be one of those features.

"Also, working environment considerations are more important now. More buildings are now being set back from section boundaries and to do that and still obtain the required floor space, you need to build higher.” He says modern and more economic materials nd methods, as well as improved earthquake resistance design, make high-rise a more feasible option than in the past. Dr Reay says the current commercial building boom, very apparent around inner Christchurch, will continue for longer than most people might think. “A recent survey in Australia showed that the average office worker now requires 50 per cent more office space than in the past.” He says the common wisdom that computers would displace white-col-lar workers has not proved to be true.

“It seems that computers are just helping the same number of peojfle to produce more and ijetter output.”

Dr Reay also predicts an increase in the use of structural steel in new commercial buildings. He says two inner-city developments to be commenced next year will be in structural steel and more will follow. About 20 steel buildings are currently under design or construction in Auckland, he says.

The reason is that the cost of structural steel has not risen at the same rate as other materials; and design and fabrication techniques will reduce many of the problems and costs associated with the material in the past. One of the major recent innovations in steel construction has been the elimination of on-site welding which has caused so many problems in the past. New design techniques allow the bolting of components on site.

“This will result in buildings going up a lot faster.” To illustrate, Dr. Reay says developments in concrete construction have reduced the construction time of a highrise building from one floor per month, 10 years ago, to one floor every one to two weeks. In steel, however, it is now possible to put up two to three floors a week. “This move to steel will make quite a change for engineers in New Zealand. There would be quite a few consulting engineers in New Zealand who have not ever had anything to do with steel construction.

“Steel offers a lot of advantages over concrete in terms of weight, also,” Dr Reay says.