The $7.5 billion Government Employees Superannuation Fund (GESB) is opening its doors for the first time to unlisted property and other direct asset classes.

The WA-based GESB is currently looking closely at unlisted property as a new asset class, said Sharon Hicks, the fund's chief investment officer.

Till date, the fund's unlisted component is made up of private equity investments.

"This time in the market presents us with the opportunity to fully capitalise on the unutilised capacity in our illiquidity risk budget," said Hicks.

Other direct asset classes including unlisted infrastructure is on GESB's agenda, although Hicks said the firm's investment process was about "prioritising opportunities" and the fund plans to tackle adding new asset classes one step at a time.

Credit investments are on the list, although it may not be a permanent addition and more of an opportunistic addition, she said.

"Allocation to credit would be part of a more dynamic approach, where we won't have it as a permanent addition in our portfolio but more as an allocation when the risk reward and correlation characteristics are sufficiently attractive," she said.

The fund is also closely reviewing its entire portfolio, and adopting a "return to basics" approach to its investments.

"[We're] making sure that cash and core cash is not enhanced cash and credit for example," said Hicks.