PURPOSE: To make it possible to easily mount end materials to a face material.

CONSTITUTION: End materials 21 mounted to corners connecting face materials 18 constituted of gypsum boards to a face material 20 are formed of paper, and when the end material 21 are mounted to the face materials 18 and 20, starch paste easy to handle can be used and, at the same time, no staple is required. When a vinyl cloth 22 is stuck on gypsum boards, no uneven step can be made with the end materials 21, and the labor in putty treatment work of ground treatment necessary for sticking the vinyl cloth 22 on them is reduced.