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.