1. Facts of recognition;

A. On January 18, 2017, the Plaintiffs are the Intervenor joining the Plaintiff (Counterclaim Defendant) (hereinafter “ Intervenor joining the Plaintiff”) (hereinafter “ Intervenor joining the Plaintiff”).

(2) Seoul Jongno-gu E and F Ground Education and Research Facilities (hereinafter referred to as “instant building”)

) New construction works (hereinafter “instant construction works”)

(2) From January 18, 2017 to June 15, 2017, the construction of this case actually continued from January 18, 2017 to September 20, 2018 (see the second appraisal report). The Plaintiffs’ Intervenor is the joint owner of the instant construction. The Plaintiffs’ Intervenor is the construction of the instant construction. (2) The Defendant is the owner of the Seoul Jongno-gu G Site and the first floor housing and neighborhood living facilities (ground 1st, ground 1st floor) adjacent to the construction site of this case (hereinafter “instant adjacent buildings”).

B. The Intervenor, who is the contractor of the instant construction and the instant adjacent building, started the Excavation Construction among the instant construction works on February 15, 2017. (2) Due to the instant construction works, serious cracks occurred on the wall surface and the wall surface of the underground room of the instant adjacent building owned by the Defendant, and the Defendant notified the head of the site office of the Plaintiffs’ Intervenor as to the defects caused by the construction and the occurrence of damages.

3. Accordingly, the plaintiffs' assistant intervenor prepared a safety construction confirmation letter of compensation for damages on April 18, 2017 and gave it to the defendant, and the main contents of which are as follows:

Safety Execution Certificate for Compensation for Damage

1. Construction name: Jongno-gu Seoul E, F multilateral-household and construction works for the new facilities;

3. trial works: Intervenors assisting the Plaintiffs; and

4. Civil petitioners: Defendant (G owner).

5. Construction period: In performing the above construction work from February 15, 2017 to June 15, 2017 (Civil Works) for eight months after June 15, 2017, the above contractor cannot exclude de facto damage to civil petitioners in any form. Nevertheless, on the premise that construction can be executed based on the civil petitioner’s understanding and understanding.