1. The plaintiff's claim is dismissed.

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

1. Details of disposition;

A. The Plaintiff is a constructor who runs a construction business.

2) The Plaintiff contracted the construction work of B apartment (one construction section, the construction period from March 31, 2016 to September 30, 2018; hereinafter “instant apartment”) with the Defendant and constructed the instant apartment construction work (hereinafter “instant apartment construction”).

B. From September 3, 2018 to January 18, 2019, the Board of Audit and Inspection conducted an audit on the actual condition of operation of the noise reduction system between apartment floors, such as prior recognition of the floor soundproof structure, construction, performance evaluation, etc., for apartment construction projects implemented by the Defendant, etc.

2) As a result of the measurement of noise between floors for the total 191 households of apartment units scheduled to move in at the completion stage by the Board of Audit and Inspection, 184 households showed that the actual performance grade was lower than the prior approved performance grade, and 114 households among them were below the minimum performance standard.

3) As a result of the inspection conducted by the Board of Audit and Inspection of the noise-preventive performance of the sample generation prior to the execution on the 89 site where the sample generation was located in the 115 construction sites conducted by the Defendant, it was confirmed that the noise performance was measured after the 31 construction sites including the instant construction sites, which did not measure the performance of the sample generation noise or 2 to 382 days after the commencement of the construction works.

4) As a result of the 31 construction sites ordered by the Defendant by the Board of Audit and Inspection, it was found that the 27 construction sites failed to maintain a flat of less than 7 meters per 3 meters per 3 meters per each of the three meters prescribed in the criteria for recognition and management of the structure blocking the shock of the floor of multi-family housing (amended by the Notice No. 2019-622, Nov. 8, 2019; hereinafter the same shall apply).

5) In announcing the audit results on April 18, 2019, the Board of Audit and Inspection shall execute with respect to the Defendant in breach of the standards specified in relevant laws and regulations, construction specifications, etc. or shall have at least the minimum performance standards for blocking floor soundproof noise.