The seventy year old Tower building on Wellington’s waterfront, originally built for Government Life Insurance, is to receive a major makeover. In the early 1930's - with the memory of the destructive power of the Napier earthquake still fresh in their minds - the buildings designers detailed a riveted steel frame, concrete encased, with a number of reinforced concrete walls. Today’s new owner requires additional levels to the building as well as car parking.

Good records of the existing building were available and Holmes Wellington documented the alterations required - including the addition of lifts and mezzanine car parking - to bring it into the 21'st century. The non-linear time history analysis of the structure - with its four additional top levels – revealed that some local strengthening to some parts of the ground floor walls and columns only was required in order to achieve seismic performance equivalent to that of a modern building. These top levels will be constructed from steel frames built off the existing concrete roof.

The project has involved some exploratory work on the structure, and consideration has been given to the results of some previous full scale model testing by others. The assessment of the building’s performance has followed the recommendations of FEMA 356, the detailed United States document that is specifically written for assessing and improving buildings to resist earthquake action.