Helicopters are preparing to take to the air to survey fresh damage across the charred and smouldering Port Hills as the deadly fires continue to burn for a fifth day.

At least one Christchurch primary school is closed and about 1000 people cannot go back to their homes this morning. But last night was one of the quietest for firefighters since the destructive wildfire started on Monday.

Several large flare-ups overnight near Dyers Pass Rd and Summit Rd were doused before they could breathe more life into the enormous blaze.

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Live blog: Quieter night for Christchurch, no homes destroyed overnightt


Now helicopters were getting ready to go up and give emergency workers an overview of any fresh destruction.

"They'll probably have a thermal-imaging camera and they'll be looking for hotspots. They'll also look to see if the fire has advanced anywhere overnight and then they'll make decisions on what they see," said Fire Service southern communications manager Riwai Grace.

He said the aerial survey would give everyone a vital overview before they head back out.

"In conjunction with the other commanders they'll make the plan of attack on how and what they're going to do today and where the resource is going to be and which areas are potentially going to be in for an interesting day. They'll look at weather conditions, wind conditions, and what type of fuels are in the area."

He said there were no reports of further damage overnight.

Vital fire retardant supplies are being flown from Australia as scores of firefighters continue to tackle the blaze that now spans 2075 hectares across the Port Hills.

This morning Cashmere Primary School said it would not be reopening this week.

The Education Ministry said there were no reports of other schools or early childhood centres closing because of the fire.

A state of emergency remains in place and police cordons will not be lifted until tomorrow at the earliest.

Christchurch Civil Defence controller Dave Adamson said the area behind the cordons was still dangerous.

Ground crews and air crews will continue to operate today and focus on the perimeter of the fire zone.

Light rain has been falling across Christchurch overnight and this is expected to continue today, coupled with high humidity levels.