To strengthen or demolish : the financial challenges facing unreinforced masonry buildings in New Zealand

Abstract

Auckland, New Zealand’s largest city continues to be dogged by both the high cost and short supply of domestic housing. A combination of high immigration, high material costs, a lack of forward planning at both Governmental and Local Authority level and a shortage in the number of qualified tradespersons has placed considerable pressure on the domestic housing market, ensuring an ongoing shortfall in the number of suitable building stock to meet population requirements. Compounding this building pressure is an impending workload from legislation recently passed that will require the strengthening of all earthquake suspect buildings to a minimum of 35% of the New Building Standard, within time periods ranging from 15-35 years and irrespective of the earthquake zone within which the building is located.

It will examine, through a series of case studies, the financial implications the legislation will have on the continued life of our small-scaled earthquake prone “home shop” unreinforced masonry buildings, many of them heritage buildings that make up a portion of the urban fabric in the many small towns and suburban communities within New Zealand. The “home shop” identifies a particular of style of Edwardian building built largely between the 1880s and 1930s, where the building owner was also the retailer who lived on the premises, usually in accommodation on the upper floor. These buildings number in the hundreds, and the financial and physical resources needed to implement this strengthening regime, assuming economic feasibility, will add further stress to the already stretched building industry and alter irrevocably the urban fabric of many of New Zealand’s towns and cities.