1. The plaintiff's appeal is dismissed.

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

The purport of the claim and appeal is the purport of the appeal.

1. The reasoning of the court of the first instance’s explanation concerning the instant case is as follows. The Plaintiff’s assertion emphasized or added by this court is identical to the description of the reasoning of the first instance judgment, except for adding “3. Additional Judgment” as to the assertion that the Plaintiff emphasizes or added by this court. As such, this is acceptable in accordance with the main sentence of Article 420 of the Civil Procedure Act.

2. Each “this Court” of the Parts 3, 5, 9, 6, and 12 shall be applied to a “court of the first instance” of the first instance judgment.

Part 4 of the first instance judgment " July 4, 2015" is dismissed as " July 14, 2015" in Part 4.

From the sixth side of the judgment of the court of first instance, the 7th "20,60,00 won" shall be deemed to be "22,660,000 won (including value-added tax)", and the 33,030,000 won (including value-added tax) of the 6th parallel shall be deemed to be "33,030,000 won (including 10,370,000 won 22,660,000 won)" of the 6th parallel (including value-added tax).

3. Additional determination

A. The gist of the Plaintiff’s assertion 1) Since C corporation, the main contractor, the non-existence of the grounds for nonperformance, supplied by the Defendant from Yangcheon-gu Seoul, changed the date of completion into six months after the date of completion due to the design change, delay of civil engineering works, and the wintering construction, regardless of the Plaintiff, the construction period under the instant contract was extended due to the change in the construction completion date of the original contract. Accordingly, the remaining completion date until the original completion date cannot be deemed as the Plaintiff’s nonperformance of obligations under the instant contract. Furthermore, the instant contract does not include exposed concrete construction, and the non-construction cannot be deemed as the Plaintiff’s nonperformance of obligations under the instant contract. Accordingly, the Defendant’s termination of the contract is null and void. (ii) Even if the Plaintiff’s nonperformance of obligations due to set-off of damages claim and damages liability against the Defendant arising therefrom, even if there were damages liability against the Plaintiff.