Wellington Hospital needs to spend $5.4 million on construction to fit in its new scanning equipment.
The hospital has had long waiting times for MRI, CT and other scans for years and some of its equipment is on its last legs.
It has done two phases of radiology upgrades so far and is now embarking on a third worth $13.6m over the next three years.
About $6m is for imaging equipment, but more than $5m is budgeted for building work. Most of the spending will be next year.
"Phase 3 involves redeveloping the two cardiac catheter laboratories, the electro-cardiologypacing laboratory and the angiography laboratory and replacing end of life equipment in these four laboratories," a board paper from a public-excluded meeting in June, released under the OIA, said.
The regional hospital in Newtown has plans to shift a lot of services around, creating more space for a relocated Emergency Department and Intensive Care among other services.
In the meantime, some patients will still have to be sent to private scanning providers, though quite how much that will cost is unclear.
The June board paper refers to $2m in operating costs over three years, however, previous documents have suggested up to $7m would be needed for outsourcing next year alone.
Read the relevant section of the June board paper (PDF1.4MB)