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The Department issued a practice advisory in June 2005 highlighting issues of concern and emphasising recommended good practice. It urged designers and building officials to keep themselves informed of the latest recommendations from researchers and reminded them of the need to follow NZS 3101 Amendment No 3. The design details in this amendment were incorporated in further tests at the University of Canterbury and performed satisfactorily.

For the buildings identified to be of potential concern in Christchurch and Wellington, the Department supported the territorial authorities in following up with owners. Through the respective councils, the Department offered to meet with building owners to explain the context of the Department’s investigations and the potential concerns about their buildings.

For the two buildings in Christchurch, the Department advised the Council in October 2004 and owners were advised by the Council. In February 2005, a Department representative, Council representatives and the survey consultant met the owners. Both owners have since reviewed the hollowcore floors in their buildings.

In Wellington, 13 buildings were brought to the attention of Wellington City Council in May 2005. The Council wrote to all those with a registered interest in each building advising of potential concerns with hollowcore floors. No requests for meetings were received. The Council has included the buildings in its list of those that are potentially earthquake-prone under section 122 of the Building Act.

In October 2006, the Department brought together a special study group to prepare guidance material for designers and building officials on assessing existing buildings and designing remedial measures. Recommendations from the group are expected to be published in 2007. Guidance material will then be prepared for new buildings, and recommendations made for any necessary changes to NZS 3101, the concrete design Standard.

A paper has been prepared summarising the Department’s investigations and promoting good practice. This will be presented to the annual conference of the New Zealand Society for Earthquake Engineering in Palmerston North in March 2007 [12].