The closure to Victoria Avenue near the City Bridge has been extended for an extra three days to allow for the safe removal of the front of Thain's Building.
The bottom CBD block was due to be opened today but the closure will remain in place until Friday.
A council spokesperson said further closures may be advised.
A one-way traffic system is in place along Taupō Quay between Victoria Ave and St Hill St until Friday August 23.
The detour for northbound traffic heading to the City Bridge is via St Hill St, Ridgway St, Drews Ave, Taupō Quay near the i-SITE building, and back to the City Bridge.
The restrictions are in place daily between 9am and 4.30pm.
Cordons are in place to keep pedestrians away from the demolition and council staff will be on site to guide pedestrians.