An apparatus for housing a component comprising: a case including a bottom portion, a side portion which extends upward from the bottom portion, and configured to accommodate a component; and a cover which covers the case, wherein the side portion includes: a first surface which faces the outside of the case; a second surface which faces the inside of the case; and a joining surface connecting the first surface and the second surface and configured to join to the case, wherein the joining surface is coated with a sealant and includes a first joining surface and a second joining surface having heights different from each other, wherein a ratio of a width of the first joining surface to a width of the second joining surface is in a range of 1:1 to 1:2, wherein the first joining surface is connected to the first surface, the second joining surface is connected to the second surface, and the first joining surface is formed to be higher than the second joining surface, characterized in that the second joining surface and the cover are spaced apart from each other, and the spaced-apart space between the second joining surface and the cover is filled with the sealant, wherein a first chamfer is formed at a boundary at which the first surface and the first joining surface join together, and a second chamfer is formed at a boundary at which the second surface and the second joining surface join together, a third chamfer is formed at a boundary at which an outer surface of the cover and a joining surface of the cover join together, wherein a first sealant bead and a second sealant bead are individually joined to the first surface and the second surface,wherein the first sealant bead is formed at a region in which the cover, the first surface and the first joining surface join together, and the second sealant bead is formed at a region in which the second surface and the second joining surface join together. a case including a bottom portion, a side portion which extends upward from the bottom portion, and configured to accommodate a component; and a cover which covers the case, wherein the side portion includes: a first surface which faces the outside of the case; a second surface which faces the inside of the case; and a joining surface connecting the first surface and the second surface and configured to join to the case, a first surface which faces the outside of the case; a second surface which faces the inside of the case; and a joining surface connecting the first surface and the second surface and configured to join to the case, wherein the joining surface is coated with a sealant and includes a first joining surface and a second joining surface having heights different from each other, wherein a ratio of a width of the first joining surface to a width of the second joining surface is in a range of 1:1 to 1:2, wherein the first joining surface is connected to the first surface, the second joining surface is connected to the second surface, and the first joining surface is formed to be higher than the second joining surface, characterized in that the second joining surface and the cover are spaced apart from each other, and the spaced-apart space between the second joining surface and the cover is filled with the sealant, wherein a first chamfer is formed at a boundary at which the first surface and the first joining surface join together, and a second chamfer is formed at a boundary at which the second surface and the second joining surface join together, a third chamfer is formed at a boundary at which an outer surface of the cover and a joining surface of the cover join together, wherein a first sealant bead and a second sealant bead are individually joined to the first surface and the second surface,wherein the first sealant bead is formed at a region in which the cover, the first surface and the first joining surface join together, and the second sealant bead is formed at a region in which the second surface and the second joining surface join together.