The NZ Defence Force says it'll be another day before the deep clean is finished at the building where a positive Covid-19 case worked.
Around 1300 staff work in Defence House, in Wellington, and have been working from home while the deep clean was underway.
The deep clean is expected to be finished tomorrow so staff can return on Thursday, says Lieutenant Colonel Darren Bec, executive officer to the Office of the Chief of Defence Force.
"This is a very deliberate and methodical process so we are flexible with this timeframe and are not going to rush the process," he told 1 NEWS in a statement today.
"The whole building needs to be cleaned, checked and formally handed over prior to any re-occupation."
He says safety of personnel and those using Defence House is "paramount".
Once staff return to the building, they'll be following stricter health protection measures.
"These include restrictions on large gatherings, distancing, focussed tracing precautions and visitor controls," Bec says.
He says the extra precautions will be in place until further notice.
Two NZDF staff have tested positive for Covid-19, a serviceperson in the Auckland quarantine facility and a civilian worker who lives in Wellington.