AAP Engineering Pty Ltd v Fernlog Pty Ltd

In the case of AAP Engineering Pty Ltd v Fernlog Pty Ltd, the primary dispute centred around allegations of breach of a commercial lease by the defendant, Fernlog Pty Ltd. The plaintiff, AAP Engineering Pty Ltd, sought relief in the Supreme Court of New South Wales, arguing that Fernlog had breached the lease by not adhering to certain terms, including the payment of electricity and water bills. Fernlog, in turn, filed a cross-claim for restitution, asserting that AAP had overcharged for electricity and water, claiming that these utilities were not separately metered as required by the lease.

The court was tasked with interpreting the lease to determine whether the electricity and water usage was indeed "separately metered" as stipulated, and whether Fernlog could recover payments made towards AAP's electricity bills on a restitutionary basis. Additionally, the court needed to assess if the parties had adopted a common understanding of their legal relationship, which could establish a conventional estoppel.

The court found that the lease did not require the utilities to be separately metered, thus the plaintiff was not entitled to the additional payments for electricity and water. Furthermore, the court held that the parties had not shared the same assumption about the terms of their legal relationship, and therefore, a conventional estoppel could not be established. Consequently, the defendant was granted judgment on its cross-claim for restitution, and the plaintiff was ordered to pay the defendant's costs of the proceedings. The parties were also directed to bring in Short Minutes of Order to reflect the amounts found to be owed under the cross-claim, and to return the exhibits after 28 days.