1. The defendant's appeal is dismissed.

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

Purport of claim and appeal

1..

1. Basic facts

A. The Plaintiff subcontracted the construction work of electricity and lighting to “C” (hereinafter “instant construction work”) from the Defendant and completed the construction work from June 2015 to September 9 of the same year.

B. The Defendant paid KRW 25 million to the Plaintiff as the price for the construction as above.

[Ground of recognition] Facts without dispute, entry of Gap evidence 1 to 3, purport of the whole pleadings

2. The assertion and judgment

A. The gist of the party’s assertion argues that the Plaintiff agreed with the Defendant on KRW 20,00,00 for the first construction cost of the instant construction, but the Plaintiff, at the Defendant’s request, agreed on the additional construction and the installation of lighting fixtures outside the office (hereinafter “the instant additional construction”). Since the additional construction cost for the added portion was determined as KRW 23,487,150, the Defendant is obligated to pay the Plaintiff the unpaid construction cost of KRW 18,487,150 (=43,487,150 - 25,00,000), and the delay damages therefrom.

The defendant asserts that the plaintiff shall pay to the plaintiff KRW 25,00,000,00 in total, including the construction work of this case and the additional construction work of this case. Since the construction work claimed by the plaintiff is unreasonable, the plaintiff's assertion is without merit.

B. Comprehensively taking account of the evidence and the appraisal result of the first instance court’s appraiser D, the first estimate amount of the instant construction was KRW 24,120,000, and the reasonable construction cost of the instant additional construction is 22,545,379.

Comprehensively taking account of the evidence revealed in the above facts, the following circumstances, namely, the appropriate construction cost of the instant supplementary construction, which was KRW 22,545,379, was close to the Plaintiff’s assertion, and only the appraisal of the instant supplementary construction cost was conducted on the premise that the initial construction cost of the instant supplementary construction was KRW 20,000,00,00 at the time of the first instance judgment. The Defendant did not raise any objection thereto.