Firefighters on the Port Hills are focusing on creating a 50 metre wide edge around the 24 kilometre long perimeter of the fire today.
Incident controller Steve Kennedy said 16 crews have taken over from the nightshift and will be working with diggers and a bulldozer to make the edge and extinguish hotspots, before stronger winds developed on Sunday.
Up to seven helicopters will also be fighting the blaze from the air before stronger winds arrive, he said.
"The safety of our crews and the public is still a major consideration for us, as this is an active fireground," Kennedy said.
"We have been able to get almost all the residents home but they all know that the fire is not out, and they may have to evacuate again at short notice."
He asked the public to stay away from the whole summit, including Dyers Pass Road, to allow fast and easy access for fire trucks, tankers and other emergency service vehicles.
Kennedy said satellite imagery has helped Fire and Emergency to better the define the area that has been burnt within the perimeter and it would be surveyed again using thermal imaging tonight.
He also warned that the fire danger remained very high right across Canterbury, and asked the public not to carry out any activities that could spark another fire.
Prominent Port Hills site reopens
Christchurch's Sign of the Kiwi cafe has reopened after being closed for two days because of the Port Hills fire.
Owner Eric Devos said he was expecting a quiet day because walking tracks and nearby Victoria Park were closed, but the loss of two days' trade was not a big deal.
"Kiwis are resilient, especially in Christchurch. We went through quite a bit with the quake. It's fine, it's life, isn't it?" he said.
"The firefighters have done a great job."
Devos said firefighters seemed far better organised than in the 2017 Port Hills fires, with better communication with evacuees.