1. The plaintiff's claims against the defendants are all dismissed.

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

1. Basic facts

A. On August 18, 2015, the Plaintiff entered into a construction contract with the Defendants on the Songpa-gu Seoul Metropolitan Government D ground owned by the Defendants (hereinafter “instant construction contract”) with the construction cost of KRW 590 million (hereinafter “instant construction contract”). On December 29, 2015, the Plaintiff agreed that the total construction cost shall be KRW 600,000,000, including extended construction works and elevator construction works, and the additional cost shall not be claimed.

B. The Plaintiff completed all of the construction works under the instant contract, and the Defendants paid all the remainder of the construction cost, excluding the warranty bond of KRW 10 million.

[Ground of recognition] Facts without dispute, Gap evidence 1 to 3, Eul evidence 1 to 5, the purport of the whole pleadings

2. Determination on the cause of the claim

A. First of all, the gist of the Plaintiff’s assertion: (a) at the time of concluding the instant contract, the Plaintiff agreed not to claim the additional construction cost; (b) it refers to the additional expansion portion of the construction cost on the contract and drawing; and (c) the Defendants demanded construction of the total of 16 square meters of the 1st floor room of the first floor without drawing drawings and the 8th floor space of the 8th floor space, which is not in the

Next, the plaintiff did not submit a letter of performance guarantee for defects because the defendants did not pay the remainder of the construction cost, and it is improper to deduct the amount of KRW 10 million from the construction cost as the warranty bond for defects.

B. The following circumstances are that the Plaintiff and the Defendants, after the commencement of the instant construction project, have expressed their opinions on the construction cost, such as additional construction work, and the Plaintiff appears to have agreed not to claim any additional construction cost, and thereafter, the Plaintiff and the Defendants were to have agreed not to claim any additional construction cost.