The appeal is dismissed.

The costs of appeal are assessed against the Plaintiff.

The grounds of appeal are examined.

1. As to the establishment of the right to claim damages under the lease agreement

A. In a case where a fire, which occurred in the part of a building owned by a lessor that was partially leased for use and profit-making, destroyed the part of the building that was not the leased building (hereinafter “non-leased part”), and the lessor suffered property damage therefrom, if the lessee proves that the lessee breached the duty of preservation and management, such as providing the cause of the fire, and that there was a proximate causal link between the lessee’s breach of the duty of preservation and management, and the damage to the non-leased part of the building. In a case where the damage to the non-leased part of the building falls under ordinary damages due to such breach of duty, or where the lessee is deemed to fall under damages due to special circumstances that the lessee knew or could have known, the lessee is liable to compensate the lessor for the damage to the non-leased part pursuant to Articles 390 and 393 of the Civil Act (see Supreme Court en banc Decision 2012Da86895, 2012Da86901, May 18, 2017).

In light of the above legal principles, the lower court’s rejection of the Plaintiff’s claim on behalf of the Defendant for damages due to nonperformance under a lease agreement with the Defendant is justifiable, and did not err by misapprehending the legal principles on the scope of damages due to the lessee’s nonperformance

2. As to the establishment of claim for damages caused by tort

(a) An accident caused by a defect in the installation or maintenance of a structure shall not mean only the defect in the installation or maintenance of the structure causes the occurrence of the damage, but also the damage caused by an accident if the defect in the installation or maintenance of the structure causes the common cause of the accident.