The Southern District Health Board is expecting most of the work to be completed by mid-February.
While slightly later than the board had hoped, the organisation had previously said it would not commission the final part of a $14.8 million project as Christmas approached.
That decision followed issues with the initial 14-bed section of the project, when problems with air tightness in the ward's isolation room meant a facility intended to open in December instead did not open until March 8.
Those delays pushed back the planned opening date for the additional 10 beds and the full commissioning of the new critical care unit, which incorporates intensive care and high dependency services.
Board chief executive Chris Fleming said work on the ward was progressing as planned.
Framing was completed except for a new public toilet, wall linings almost finished, and ceilings half done.
"The removal of temporary ducting and subsequently connecting up the final heating, ventilation, and air conditioning ducting to stage one in early December has allowed [contractor] Naylor Love to progress with finishing building works in the area around the main service riser and new entrance to the ICU.
"The remainder of stage two is complete with minor work to occur over the next three to four weeks."
The new unit, which replaces cramped, dark and outdated facilities, will have natural light in most areas, private rooms, noise dampening technology new monitoring technology, and more space for families, staff and students.
"Naylor Love intends for commissioning of the electrical, security and data systems to run in parallel with completion of the final two to three weeks of construction," Mr Fleming said.
The whole project was expected to be finished within weeks, barring the heating and ventilation systems.
