1. The plaintiff's appeal is dismissed.

2. The costs of appeal shall be borne by the Plaintiff.

Purport of claim and appeal

The first instance court.

1. Basic facts

A. The Plaintiff is a person who engages in the interior design business, etc. on the fifth floor of the building located in Gangnam-gu Seoul Metropolitan Government with the trade name of “D,” and the Defendant is a person who operates the interior hall with the trade name of “F” in Seongbuk-gu Seoul Metropolitan Government E.

B. On October 2013, the Plaintiff entered into a contract with the Defendant for the extension of interior and outside interior interior interior of the instant F-M-type building (hereinafter “instant construction contract”) under which the construction period was from October 24, 2013 to November 30, 2013, and the construction cost was determined as KRW 27850,000,000 (hereinafter “instant construction contract”).

C. Around November 30, 2015, the Plaintiff completed the instant construction work and received payment of KRW 2785,000 from the Defendant.

[Ground of recognition] The fact that there is no dispute, entry of Gap evidence 2, video of Eul evidence 3, testimony of Gap witness G in the trial, purport of whole pleading

2. The assertion and judgment

A. In the process of performing the instant construction, the Plaintiff asserted that the Plaintiff agreed with the Defendant to perform additional construction works, such as installation and construction of natural materials of external walls, steel framed of external signboards, and internal or indirect steel framed works, other than the instant construction works, (i) KRW 8 million for the said additional construction works (i.e., KRW 8 million for natural materials of external walls, KRW 2.5 million for the steel framed of external walls, KRW 9 million for internal or indirect steel framed works, and KRW 3.8 million for the said additional construction. Accordingly, the said additional construction was completed.

Therefore, the defendant is obligated to pay the plaintiff the above additional construction cost of eight million won and damages for delay.

B. In order to claim additional construction costs in the 1 construction contract, there should be separate agreements between the contractor and the contractor on the implementation of the additional construction and the payment of the additional construction cost. If there is an express agreement on the additional construction, such agreement should be followed, but in the absence of such agreement, in particular, in the construction contract, which is the total amount contract other than the unit price contract, the contractor may also be