1. Of the judgment of the court of first instance, the part against the defendant in excess of the following amount ordered to be paid shall be revoked.

1. Basic facts

A. On April 13, 2015, the Plaintiff entered into a contract for construction works with the Defendant (hereinafter referred to as “instant construction works”) by setting the construction cost of KRW 34,000,000 (additional tax separately), from April 13, 2015 to May 5, 2015 (hereinafter “instant construction contract”). Article 4 (other Matters)(a) of the said contract for construction works states that “The content of the construction works shall be based on the attached estimates, and additional construction works shall be borne separately by A (referring to the Defendant).”

B. On May 5, 2015, the Plaintiff completed the instant construction work.

C. The Defendant paid KRW 24,00,000 in total as construction cost under the instant construction contract.

[Judgment of the court below] The ground for recognition is without merit, Gap evidence Nos. 1 and 3, and the ground for appeal

2. The parties' assertion

A. The main purport of the Plaintiff’s assertion was to complete the instant construction project under the instant construction contract, and during the instant construction project, additional construction works, such as construction works with wide size of the main area not included in the instant construction contract at the Defendant’s request, and construction works for open main walls. The Defendant is obligated to pay the Plaintiff the unpaid construction cost of KRW 10,000,000, additional construction cost, additional tax, and damages for delay.

B. As the Plaintiff’s summary of the Defendant’s assertion occurred in the course of performing the instant construction, the Plaintiff is obligated to pay KRW 17,954,00,00 necessary for defect repair to the Defendant. The Defendant’s service of the preparatory document on June 8, 2017, set off the Plaintiff’s damage liability of KRW 17,954,00 against the Plaintiff and the Plaintiff’s damage liability of KRW 17,954,00 against the Plaintiff’s construction cost and additional construction cost on an equal basis.

3. Determination

A. As to the Plaintiff’s claim for the construction cost of this case, the construction cost of this case under the construction contract of this case is KRW 34,000,000, and the Defendant among them.