1. Of the judgment of the court of first instance, the part against the plaintiff corresponding to the following additional payment order shall be revoked.

1. Basic facts

A. The Plaintiff is a company specialized in construction of the overall convenience facilities for the disabled, and the Defendant is the person who requested the Plaintiff to install the convenience facilities for the disabled to change the purpose of the use of three floors among the Defendant’s headquarters building located in Gangnam-gu Seoul Metropolitan Government (hereinafter “instant building”) from “general office” to “Council members.”

B. On March 17, 2017, the Plaintiff entered into a construction contract with the Defendant on the construction of facilities for convenient persons with disabilities (hereinafter “the instant primary construction”) with regard to the change of the purpose of use of the instant building, with the content that the construction cost of KRW 9,900,000 (including surtax), March 23, 2017 on the date of commencement, March 23, 2017, and March 31, 2017 on the date of completion of construction, and the addition (number, item) to other details shall be separately settled after agreement. Accordingly, the Plaintiff completed the primary construction.

C. After the first construction of the instant building, the Plaintiff agreed to submit a written estimate for construction to the Defendant on April 14, 2017 when the Defendant requested to change the place where the disabled set of the instant building was installed. Around April 14, 2017, the Plaintiff completed the installation of the disabled set (hereinafter “the second construction”).

After the instant construction, at the inspection of the competent authorities, the instant 10 items were ordered to correct the said items, and some of them were the existing buildings, and thus, the instant building was subject to an application for reconstruction without reconstruction. However, considering the period required for application for mitigation, the Defendant requested the Plaintiff to re-rout the period of approval for the change of use agreed with the lessee, while considering the period required for application for mitigation.

Accordingly, on April 19, 2017, the Plaintiff agreed to send a written estimate of additional construction works under the item of the corrective order to the Defendant for the payment of the construction cost of KRW 7,00,000 (Additional Tax Table). The Plaintiff completed the said additional construction work (hereinafter “instant third construction work”).

E. The Defendant pays only the first construction cost of this case to the Plaintiff, and the second and third construction works of this case are due to the Plaintiff’s erroneous determination.