1. The Defendant’s KRW 11,248,024 as well as 5% per annum from June 14, 2014 to March 13, 2019 to the Plaintiff.

1. Basic facts

A. On May 13, 2014, the Plaintiff received a contract from the Defendant to install a boiler installed mainly with the following content:

(hereinafter referred to as the “instant construction and the instant contract”). The construction site: payment of KRW 17,00,000 (including value-added tax) which is 40% of the construction cost at the time of the conclusion of the contract; payment of KRW 17,000,000 which is 40% of the construction cost; payment of KRW 40% of the remainder after the completion of construction; and payment of 20% of the remainder after the completion of construction;

B. At the time of the contract, the Plaintiff received KRW 17,00,000 from the Defendant, and completed the instant construction work around June 2014.

C. However, around June 13, 2014, a water leakage phenomenon occurred during the boiler test dong constructed by the Plaintiff.

The Defendant discovered the location and cause of water leakage using the heat camera equipment, etc., and found that water leakage occurred in the 5 room floor and the toilet constructed by the mother customs except 8 rooms constructed by the luminous, in that the materials used are X-cell pipes, as seen below, although the Plaintiff ordered the Plaintiff to “dubing method” among 13 rooms where heating construction was performed by the Plaintiff.

From the date of the occurrence of water leakage, the Plaintiff expressed his intention to repair defects by hearing the fact from the Defendant. However, the Defendant rejected the Plaintiff’s repair of defects and removed all the five rooms and toilets floors that occurred in the process of water leakage by leaving another business operator around June 17, 2014, by opening the five rooms and toilets floors that occurred in the process of water leakage, and installing a new X-gu heating system.

E. On October 13, 2014, the Defendant proves that the Plaintiff filed a claim with the Plaintiff for the cancellation of the instant contract and the payment of damages equivalent to KRW 19,051,976 for the construction cost, such as the said reconstruction, on the ground that the Plaintiff had removed and discarded the floor due to defective construction and that the boiler reconstruction was conducted.