1. All appeals by the Defendants are dismissed.

2. The costs of appeal are assessed against the Defendants.

Purport of claim and appeal

(b).

1. In accordance with the main sentence of Article 420 of the Civil Procedure Act for the establishment of the obligation to pay the goods price and the joint and several sureties, the part “determination on the cause of claim” of the judgment of the first instance shall be cited, and the “date of settlement” of the list shall be read as “date of settlement” and “ February 14, 2013” as “ February 4, 2013.”

2. Determination as to the defendants' defense of set-off

A. The allegation that the defendant Cheongju Construction Industry Co., Ltd. awarded a contract for the construction of a new factory building located in the Doe-si, Kim Jong-si, Kim Jong-si, Gyeng Construction Industry Co., Ltd., and the defendant Cheongju Construction Industry Co., Ltd. awarded a subcontract for the construction of the above construction, and the defendant Cheongju Construction Industry Co., Ltd. re-subcontracts the outer wall and roof construction during the above construction. Meanwhile, the defendant A supplied the panel materials from the plaintiff and completed the above outer wall and roof construction. Among the outer wall of the factory, there were defects such as the main title and gye in the part of the panel's outer steel board supplied by the plaintiff among the outer wall of the factory, which caused the following damages, the defendants set off the plaintiff'

① Defendant A incurred damages worth KRW 60 million in total in the amount of KRW 110 million in the cost of removal and reconstruction of a panel, KRW 30 million in the cost of removal and reconstruction of a panel, and KRW 20 million in the cost of outside finishing construction.

② Defendant Cheongfriendly Construction Industry Co., Ltd. suffered damages of KRW 50 million in total, and KRW 30 million in expenses for removal and reconstruction of a panel. Defendant Cheongfriendly Construction Industry Co., Ltd. incurred damages of KRW 80 million in total.

③ Even if it is not so, 30,010,332 won, which is the sum of the appraisal of the above defects, should be recognized as damages, inasmuch as the normal value of the exchange of the panel is calculated as 24,070,21 won as a result of the appraisal of the above defects.

B. Determination of Gap evidence Nos. 4-1 to 9 and Gap evidence No. 5, respectively;