Cranes are being moved into Wellington's inner city to demolish what remains of Defence House.

The building was severely damaged in the Kaikoura Earthquake.

Wellington City Council building resilience manager Steve Cody said they've got the building down to five storeys.

He said they now need to quickly take down key components of the building, which keep it stabilised.

"While the office building is relatively stable you don't want to leave it sitting there half torn down and the whole focus is getting these buildings demolished as soon as possible."