Companies specialising in the tricky task of re-levelling buildings are gearing up for a massive amount of work fixing up damaged land in Christchurch.

New Zealand building consents stalled in September with its first monthly decline in five eroding gains over the past two months.

Fletcher Building, the biggest company on the NZX 50 Index, said first-half profit will fall 10 per cent.

Fletcher Building says its first-half earnings are likely to be about 10 per cent down on the $166 million earned in the same period last year.

Construction continues on the Auckland Art Gallery extension and renovation project in the Central City.

Questions are being raised about the strength of Stadium Southland's now collapsed roof.

Global re-insurance companies will probably take the bulk of losses for claims from the Christchurch earthquake not covered by EQC, says Moody's.