1. The judgment of the court of first instance is modified as follows.

Seo-gu, Daejeon, between the Plaintiff (Counterclaim Defendant) and the Defendant (Counterclaim Plaintiff).

1. The reasoning of the court's explanation by this court is as follows, except for the cases where the letter of the reasoning of the court of first instance was written in accordance with the main sentence of Article 420 of the Civil Procedure Act, since it is the same as that of the court of first instance except for the cases where the letter of appeal No. 13, No. 17, and No. 14, 14

2. As to the part 1 of the above construction cost, barring any special circumstance, the Plaintiff is obligated to pay the Defendant the remainder of the construction cost of KRW 277,097,00 (i.e., the additional construction cost of KRW 106,531,00,000) and damages for delay thereof (i.e., the additional construction cost of KRW 170,566,000), and the Defendant is obligated to pay the Plaintiff the aforementioned defect repair cost of KRW 72,318,790, and damages for delay. 2) Accordingly, the Plaintiff seeks the payment of damages equivalent to the above defect repair cost of KRW 72,318,790 as the principal lawsuit, and thereby

The contractor may claim for the repair of the defect against the contractor when there is a defect in the object completed in the contract for work, and the contractor may claim damages in lieu of or together with the repair of the defect, unless there are special circumstances. They are in the simultaneous performance relationship with the contractor's claim for the payment of the work price. Thus, if the contractor holds the repair of the defect or the right to claim damages and exercises them, the contractor's obligation for the payment of the work price is not attributable to the delay of performance (this relationship applies to the existence of the delayed performance liability for the damages to the contractor who holds the claim for the work price under the same contract and exercises the right to claim the work price under the same contract) and the contractor shall be deemed to have been discharged immediately after the date when the contractor expresses his intention of set-off with the contractor's claim for the remainder of the construction price.