In October 2019 it was announced the workshops would get $20million from the Provincial Growth Fund to go towards revitalisation.
That included earthquake-proofing ageing buildings, getting rid of asbestos and overhauling old equipment.
Staff numbers are expected to grow from about 23 to 100 as it becomes a multipurpose workshop.
In an update this week a KiwiRail spokesman said the work at Hillside was already visible "...with the completion of the demolition last month of two end-of-life vacant workshops".
"More demolitions are planned to start before the end of the year".
The next step was to upgrade the main rail workshops on site, such as overhauling an ageing heavy-lift crane and traverser.
"The planned improvements for the site will allow us to maintain more locomotives and wagons, as well as undertaking new types of work, such as heavy maintenance and upgrades."
A detailed design for the main workshops was expected by the end of the year and before new construction begins.
Asked whether there may be positions available for the 37 staff working at the Bradken foundry tipped to close at the end of the year, the spokesman said there was not work available now.
Nor was Kiwirail interested in taking back the foundry after selling it to Bradken in 2012.
