A. Facts 1) The Plaintiff is a general construction company that performs construction works, civil engineering works, and the Defendant is a company that manufactures metal products and processed products. 2) On March 15, 2016, the Plaintiff contracted from the Defendant on March 15, 2016, for the construction of three factories on the ground of the emulculation (at that time, 1-1-3 of the emulculation ballast), on the ground of the Defendant. The contract amount was the total amount of KRW 655,60,000, the commencement date, and the completion date of the construction on March 25, 2016, the completion date of the works on August 25, 2016.

(3) The Plaintiff started construction on March 25, 2016 and completed the completion inspection by the Defendant, and delivered the instant factory to the Defendant on October 24, 2016. On the same day, the Defendant obtained approval for use from the time of industrialization. (4) The Defendant paid KRW 623,563,00 out of the total construction cost of the instant contract and KRW 32,037,000 ( KRW 65,600,000 in - KRW 623,563,000 in - 623,563,00 in balance).

5) Under the instant contract, the time for the payment of the price and the interest rate for delay were agreed as follows. Article 25 [Payments Payment] ① the Plaintiff, “B,” and “A” (hereinafter the same shall apply) of the General Conditions of the Standard Contract for Construction Works, may adjust the construction site, such as immediately removing or removing surplus materials, wastes, temporary materials, etc., after passing the inspection of completion of the same as “A,” and claim the payment of the price for construction. ② “A” shall pay the price for construction to “B” at the same time as the object of the contract is delivered, unless otherwise stipulated. ③ “A” shall pay the unpaid amount by adding the interest calculated by applying the interest rate for delay in payment as stipulated in the contract to the number of days from the day following the due date of payment until the due date of the payment. On November of the Standard Contract for Construction Works: 30% per annum of the contract amount: