First draft of quake-proof law was an over-reaction, but the revised version is practical and affordable.
In the aftermath of a disaster it is easy to lose your head. That is what happened when a royal commission of inquiry into the Canterbury earthquakes, followed by a building code review, suggested all New Zealand's older buildings of unreinforced masonry should have to comply with the modern code as soon as possible.
The royal commission recommended that councils be given two years to identify substandard buildings and after that, the owners be given seven years to upgrade or demolish them.
The Ministry of Business, Innovation and Employment was a little more lenient. Its code review proposed five years for identification of non-compliant buildings and a further 10 years for their strengthening. The Government adopted periods of five and 15 years in a bill introduced to Parliament when Christchurch had barely stopped shaking.
Fortunately the Earthquake-prone Buildings Amendment Bill has been delayed long enough for better judgment to prevail. This week, Building and Housing Minister Nick Smith announced the bill would be revised to give variable periods for compliance depending on the building's location. The country is to be divided into three broad zones of high, medium and low risk, depending on their distance from the collision of tectonic plates that created our shaky isles.
Only the zone of high risk - the eastern side of the North Island, Marlborough, North Canterbury and the western side of the South Island - will face the five and 15 year deadlines.
Areas of medium risk, which include Waikato, Bay of Plenty, King Country and Taranaki, will have 10 years for assessment and a further 15 years for work to be done.
Low risk regions such as Auckland and Northland will have 15 years for assessments and another 35 years for owners to decide whether to upgrade or replace the buildings.
Those with heritage listings can be given a further 10 years.
This means the wrecking ball that threatened many older town and suburban centres has been stayed. Periods of 25 and 50 years, or 35 and 60 for heritage buildings, make it much less likely distinctive older buildings in these areas will be lost. It is much more likely within those spans of time that a building will come to need substantial renovation in any case.
If it is on the council's earthquake non-compliance list, the strengthening can be done with the renovation. That is already the way the code is enforced by many councils, and it is the only sensible way. The risk of an earthquake is too low to justify doing major remedial work to public and commercial buildings that predate the adoption of today's earthquake resistant standards in 1976.
One study calculated that in Auckland the bill's original requirements would have cost $3 billion and would have taken 4000 years to save a life. Such is the rarity of earthquakes of a life-threatening magnitude.
After experiencing one, it can seem sensible to take excessive precautions. Thankfully, that phase has passed and our older stone buildings will be allowed to stand for a while yet.