1. Of the judgment of the first instance court, the part against the Defendant (Counterclaim Plaintiff) is modified as follows.

1. Basic facts

A. A Co., Ltd. is a project proprietor who constructed and sold a total of 1,194 units of C apartment located in Daegu Northern-gu B (hereinafter “instant apartment”). The Defendants are the owners of the instant apartment as the sectional owners of the instant apartment.

B. On December 30, 2009, while the lawsuit of this case is pending, A Co., Ltd. divided the company on December 30, 2009, and established Plaintiff CN, Inc. succeeded to the rights and obligations regarding housing projects, such as the apartment of this case, and Plaintiff CN took over the litigation of this case.

(hereinafter referred to as “Plaintiff” without distinguishing Company A and Plaintiff CN.

On December 29, 2000, the apartment of this case obtained approval from the Daegu Metropolitan City Mayor for the housing construction project.

The floor structure of the apartment of this case was designed and constructed with a thickness of 245 meters, such as concrete slab 135 meters, light-weight concrete 70 meters, cement mortar 40 meters, etc.

E. The Defendants filed a dispute mediation with the Central Environmental Dispute Mediation Committee (hereinafter “Committee”) to seek damages against the Plaintiff on the ground that sound from the upper floor of each apartment unit of this case exceeds the tolerance limit and suffered damages.

Accordingly, the Committee measured the performance of blocking the floor soundproof noise for three households of the apartment of this case in the field, and as a result, measured the impact of each household in the light level of 61 Silx (dB) through 69 Silx (dB).

F. On May 15, 2008, the commission decided on May 15, 2008 that the Plaintiff should pay the expenses incurred in installing facilities to prevent noise between the floors of the instant apartment.

G. The cost of installing the said tea facilities was determined based on the construction cost of KRW 58,00 per square meter by calculating the area necessary for tea construction, such as the living room of each household of the instant apartment complex, but the commission is the housing construction standard.