A. On September 7, 2015, the Plaintiff entered into a contract with the Defendant to accept a subcontract with the Defendant by setting the construction cost of KRW 77,000,000 and the construction period from September 7, 2015 to October 6, 2015, among B boiler and pipeline replacement works (hereinafter “instant construction work”).

B. During the construction process of the instant construction project, the Defendant failed to perform some construction works upon the Defendant’s request for change of construction works, or carried out additional construction works, and the construction price was increased by KRW 12,978,183 due to such increase or decrease in construction details.

C. The Plaintiff completed all the instant construction and additional construction around the expiration of the construction period, and received KRW 23,100,000 out of the construction price from the Defendant.

[Ground of Recognition] Facts without dispute, entries in Gap evidence 1, 2, and 3 (including each number), images, and the purport of the whole pleadings

2. According to the facts of recognition as to the Plaintiff’s claim, since the Plaintiff completed all of the instant construction and additional construction, the Defendant is obligated to pay to the Plaintiff the remaining construction cost of KRW 66,878,183 (i.e., the additional construction cost of KRW 12,978,183 (i.e., the agreed construction cost of KRW 77,00,000) - the amount of KRW 53,900,000, and damages for delay calculated at the rate of 15% per annum under the Act on Special Cases Concerning the Promotion, etc. of Legal Proceedings from February 5, 2016 to the date of full payment after the duplicate of the complaint was served on the Defendant.

3. As to the Defendant’s assertion, the Defendant asserts that the Defendant’s primary contract construction cost of the B boiler and pipeline replacement construction cost was reduced to KRW 6,612,815, and the Defendant supplied the Plaintiff with materials equivalent to KRW 10,193,200, the Defendant should reduce the amount of KRW 12,320,000 (= KRW 77,00,000 x 16 per cent) out of the contract construction cost.

According to the statements in Eul evidence Nos. 1 to 4, the above boiler and pipeline replacement works have been partially reduced.