The $2.8 million job to fix and upgrade Auckland's Chancery shopping, dining and office precinct is on track to be finished around Christmas.
But maintenance issues mean not all the workers will leave the site until early next year.
Graeme Birkhead, Arrow International's northern director, said much of the work was already completed on the site where around 40 people had worked daily.
Arrow won the contract for one of the inner-city's largest building repairs and upgrades and started work late last year.
The block opposite Freyberg Place at the foot of the Metropolis Residences apartment block opened in 2000 but suffered leaky building issues for many years.