1. The defendant's appeal is dismissed.

2. The costs of appeal shall be borne by the Defendant.

3. The judgment of the court of first instance is ordered.

1. Basic facts

A. On February 2, 2010, the Defendant entered into a contract with the Agju Medical Center (hereinafter “Agju Medical Center”) for the 25,500,000,000 construction cost (including value-added tax; hereinafter the same shall apply) from the Agju Medical Center (hereinafter “Agju Medical Center”). The Defendant finally changed the construction period from February 10, 201 to December 20, 2012 to KRW 36,542,00,000 through a four-time modified contract.

B. On January 27, 2012, the Plaintiff entered into a contract with the Defendant for a contract with the construction cost of KRW 341,00,000, and the construction period of KRW 31,000 from January 27, 2012 to July 31, 2012. On July 18, 2012, the Plaintiff entered into a contract with the Defendant to change the construction cost of the instant tin to KRW 597,850,00 (hereinafter “instant modified contract”).

C. The instant stone construction was completed on July 31, 2012, and the Defendant and the ASEAN completed the settlement of construction cost for the instant extended construction around December 31, 2012.

The Defendant paid the Plaintiff KRW 595,850,00 in total, including KRW 587,66,00 prior to the filing of the instant lawsuit, and KRW 8,184,00 on February 5, 2013 following the filing of the instant lawsuit (= KRW 587,66,000).

[Ground of recognition] Facts without dispute, Gap evidence 2, 3 evidence, Eul evidence 2 (including branch numbers; hereinafter the same shall apply), and the fact inquiry conducted by the court of first instance on September 26, 2013 about the ASEAN of the first instance court, the purport of the whole pleadings, as a result of the fact inquiry conducted by the court of first instance

2. The assertion and judgment

A. The Defendant, which caused the Plaintiff’s claim, requested alteration work and additional construction work for completion to the Plaintiff even after the instant alteration contract, and accordingly, the Plaintiff and the Defendant agreed to make a subsequent settlement of the specific additional expenses and carried out alteration and additional construction work. Ultimately, the Plaintiff’s additional construction work in the instant extension work has a total of KRW 724,350,000.