The Transport Accident Commission (TAC) in Victoria has relocated to purpose-built offices in the heart of provincial city Geelong, 80 km south west of Melbourne.

The move is part of the Victorian Government's pledge to build regional Victoria and sees the TAC occupy an office complex awarded a 5 Star Green Star – Office Design V2 Rating by the Green Building Council of Australia (GBCA). The certified rating evaluates the environmental potential of the building and a rating of five green stars signifies Australian excellence.

The eight level complex is more than just a new headquarters for TAC. The ground floor has a retail component and includes a gymnasium, café, travel agent and newsagent; there are also three levels of fully enclosed carparking. All up the complex will have 16,285 square metres of net letable area (NLA).

Entire Mechanical Services Project Manager Garry Muscat said ventilating the 338 space carpark, split across three levels in the TAC complex, was made more difficult by the fact that the carpark was fully enclosed and that the ceilings were low.

“The FKP Property Group was keen to look at alternatives to the traditional carpark exhaust system which would have required a lot of bulky ductwork and in some places where space was limited, ducting made from load bearing Steel-Styrofoam panel,” Gary said.

“Furthermore, the developers support sustainable energy efficient designs and wanted a cost effective system that had good performance figures. They liked the idea of using JetVent fans which had a low vertical height and were economical to run and install.”

A carpark impulse ventilation system can help to minimise major capital costs in several ways. It reduces the time it takes to install and commission, eliminates the need for expensive ducting, and reduces the pressure requirements for the main supply and exhaust fans, which therefore has the potential to lower the cost of the fan. Deciding to use a ductless system early in the building design can also reduce the level of expensive excavation required for the basement.

Ongoing power consumption costs can also be reduced by using smaller fans and controlling the speed and usage of the fans based on the demand. Removal of most of the ducting could also drop the overall cost of maintenance and repairs.

Fantech engaged a computational fluid dynamics (CFD) consultant to optimise the design and ensure the mechanical design would comply with performance criteria set out in the Building Code of Australia.

Entire Mechanical Services installed 12 JetVent mixed flow induction jet fans (JIU-CPMF-50N) and a carbon monoxide sensor driven control system to deliver optimal energy consumption performance.

“The energy efficiency and space saving characteristics of the JetVent system were duly noted by the GBCA who awarded the developers additional points for innovation in their green star accreditation,” Garry said.

Mr Muscat said the building was put into operation in January 2009 and the JetVent fans continue to perform well.