An inventory of unreinforced load-bearing stone masonry buildings in New Zealand

Abstract

Almost all unreinforced stone masonry (URSM) buildings in New Zealand were constructed between 1860 and 1910, typically in regions where natural stone was sourced from local quarries, fields and rivers. These buildings form an important part of the country’s architectural heritage, but the performance of URSM buildings during earthquake induced shaking can differ widely due to many aspects related to the constituent construction materials and type of masonry wall cross-section morphology. Consequently, as a step towards gaining greater knowledge of the New Zealand URSM building stock and its features, an exercise was undertaken to identify and document the country-wide URSM building inventory. The compiled building inventory database includes: (i) general building information, such as address, building owner/tenant and building use; (ii) architectural configuration, such as approximate floor area, number of storeys, connection with other buildings, plan and elevation regularity; and (iii) masonry type, such as stone and mortar types, wall texture and wall cross-section morphology. From this exercise it is estimated that there is in excess of 668 URSM buildings currently in existence throughout New Zealand. A large number of these vintage URSM buildings require detailed seismic assessment and the implementation of seismic strengthening interventions in order to conserve and enhance this component of New Zealand’s cultural and national identity. The entire stock of identified buildings is reported in the appended annex (688 total), including 20 URSM buildings that were demolished following the Canterbury earthquake sequence.