Is wood the answer?

Jim Anderton writes in The Press:

Wigram MP and Progressive Party leader JIM ANDERTON explains why he favours rebuilding Christchurch in wood.

‘Ridiculous” and “stupid” are how Richard Field, the Canterbury president of the Master Builders’ Federation, described my recent call to use wood as a primary construction material in the rebuilding of post- earthquake Christchurch. Setting aside the obvious question of why a building industry leader would dismiss wood in this way, the comments from Mr Field ignore mounting scientific and engineering evidence which shows that wood has the characteristics and qualities needed for a safe, modern city. As well as being safe, there are a host of other reasons why wood should form the mainstay of Christchurch’s building recovery – it is ecologically sound and sustainable, it is less expensive than many alternatives and it’s an attractive, iconic New Zealand product. There is another aspect too, and that is in the psychological recovery of the thousands of people who work in the inner city, many of whom now live in fear of working again in high-rise buildings. Those people need to feel secure, and wooden buildings, even up to six storeys high, can afford them that security.

I don’t know enough to say whether Anderton is right or wrong. I tend to think it is more likely the head of the Master Builders Federation will know what they are on about, but it would be interesting to hear reasons for why wood is or is not impractical.

Since 2007, research carried out under the guidance of Professor Andy Buchanan at the University of Canterbury has looked at the potential for commercial buildings to be constructed of wood as opposed to concrete and steel. That research was motivated in part by the Government’s wish to pursue policies towards greater sustainability; its rationale including that modern engineered wood products, along with advances in structural timber engineering and innovative design, positioned timber as a viable alternative to concrete and steel for multi-storey buildings. There are a number of other reasons to look at wood for major construction work. It is a renewable, low-energy resource.

I wonder what the cost differential is?

Another important element when it comes to safety is fire resistance. Strange as it may seem, large wood beams have excellent fire resistance because the slow rate of surface charring protects the wood inside the beams and columns. Fire safety is further increased by sprinkler systems, giving people time to evacuate buildings during an emergency.

Compare that with the collapse of the Twin Towers in New York during the 9/11 event, where the steel frame lost strength as a result of fire. That sort of collapse would be unlikely in a wooden building.

Any engineers with an opinion on this?